Don Mitchell's Blog

Life Forms On Venus? Probably Not

2012-01-23T21:50:00.000-08:00

In a recent paper, a highly respected and pioneering planetary scientist in Russia has suggested that images from the Venera-13 lander might show life forms on the surface of Venus. Dr. Leonid Ksanfomality did important work on the spectroscopy of Venus and Mars from spacecrafts in the 1970s and 1980s, and he was the first to discover that lightning was common in the atmosphere of Venus.

His latest paper has raised eyebrows throughout the planetary science community: "Venus as a Natural Laboratory to Find Life at High Temperature: Events on the Planet". In it, he claims three particular examples of mysterious objects: a moving disk shaped form, a "scorpion" shaped object, and a moving black object. I would like to present an alternative theory for these objects, which I believe is more likely. First a quick review of the camera and telemetry system of Venera-13. A broader discussion of that mission can be found here: http://www.mentallandscape.com/V_Venera11.htm

Nearing Venus, on Feb 28, 1982, the massive Venera-13 separated into a landing vehicle and a large flyby spacecraft. These encountered the planet on March 1, where the lander set down at 03:57:21 UTC. It drilled into the surface to analyze the rocks, and several minutes later, a cycloramic camera began to scan the surface through a thick quartz window. A photomultipler tube, highly sensitive and very low-noise, detected light, which was converted into 9-bit digital video.

The digital video from each of two cameras was sent to the flyby spacecraft on a meter band channel at a data rate of 3072 bits/sec. This was then relayed to the Earth via a large parabolic antenna. In a typical style of redundant design, two entirely different radio systems were used for the interplanetary transmission. On a decimeter band, the digital video was passed unchanged, as a pulse-code modulated (PCM) signal. That is, pixel values were sent as a sequence of binary numbers (with convolution error-correction code). This is also how American spacecraft transmitted data.

On a centimeter band, an older Soviet radio system sent the data using a pulse magnetron to encode the data as variable spacing between powerful microwave impulses. 512 numbers per second were transmitted, each representing 6 bits of data and parity, encoded orthogonally into 128 possible pulse spacings. This scheme is usually called Pulse-position modulation (PPM), and in Russian VIM (Vremya Impulsnoi Modulyatsii).

Here are examples of two versions of transmitted video signal. The first is sent by PCM, generally a very clear signal, but single-bit errors create a familiar "salt & pepper" noise which gets more intense later in the transmission as the signal from the flyby spacecraft apparently weakens. The second image is sent by PPM and is rather strange. The noise takes the form of light speckles, but there is no sign of errors in low order bits. Even near the end of transmission, the noise characteristics remain unchanged. My own analysis found that I could systematically undo most of this noise, making these bad looking images actually a useful source of good data.

One of the objects Dr. Ksanfomality claims might be a lifeform is the "scorpion", which is indicated by the orange arrow. But his object does not appear in the simultaneously transmitted PCM signal.

To better understand this phenomenon, let us plot the corresponding pixel values in PCM and PPM versions (with log intensity). Along the diagonal, we see the hoped-for case where both pixels have the same value. The horizontal smear around this diagonal is the result of the "salt & pepper" noise contained in the PCM signal. However, the noise in the PPM signal is far from random, resulting in a geometrically patterned constellation of points. We would expect errors in pulse-position modulation to take the form of small errors in the pulse spacing, creating low-order bit errors. But these are passed through an orthogonal code that is designed to separate those values and make error correction easier. It is quite possible that the geometrical pattern is the result of that coding.

Noise in the PPM images tends to occur along isophotes, curves of constant brightness. And this explains why it follows subtle countours and develops into interesting structures. The "scorpion" and "disk" are probably the result of this phenomenon. However, Dr. Ksanfomality also points out a third unusual feature that changes over time, a dark shape next to the Prop-V sensor, a scientific experiment that drilled into the surface to measure the physical consistency of the rock.

Here are my own processed versions of two images taken about 15 minutes apart, which show a change in the shadow on the near side of the drill (under the smaller disk at the end of the framework). In my own research, I calculated a new and more accurate camera response function, so it is fairly clear that a shadow appears in the early image and then seems to be gone in the second image. But in the Russian versions of this image, the shadow is almost black, and this appears to be the object Dr. Ksanfomality named the "black rag".

While this is not an object that moved, it is still an interesting question to ask why the shadow disappeared. The illumination on the surface of Venus is thought to be a uniform glow from the perminantly cloudy sky. However, a few years ago, Grieger and Ignatiev analyzed spectral data from the Venera-13 lander, made during its descent, and they found evidence of a near-surface cloud layer. Could a passing low-altitude cloud have caused a change in the distribution of illumination?

I hope this controversy will kindle a rewnewed interest in the mysteries of the planet Venus and lead to new missions. The Soviet Union landed on Venus 10 times, and nobody has attempted it again since the twin landers of the 1985 Vega mission.

Heavy Interplanetary Ship

2010-02-24T16:19:00.000-08:00

In 1962, Sergey Korolev, the head of the Soviet rocket program, wrote a report entitled "A Plan for the Mastery of Mars and Venus". In the previous two years, his team had made several unsuccessful attempts to send "automatic stations" to Mars and Venus. Now he tasked Maksimov's design team with the problem of sending men on orbital missions to the nearby planets.

Gleb Maksimov had designed Luna-3 and Venera-1. The Mars-1 spacecraft was an example of his modular spacecraft system, able to perform photographic fly-bys of Mars or Venus or to deliver a landing capsule. Although very young at the time, Maksimov had earned the respect of Korolev's team and the academic scientists who designed experiments for planetary probes.

Maksimov's manned spacecraft design became known as TMK, the heavy interplanetary ship (Tyazhely Mezhplanetny Korabl ). The 75 ton spacecraft would have to be assembled in space from pieces launched by the as yet unbuilt N-1 moon rocket.

A subsequent version would include crew quarters and a hydroponic greenhouse to supply food and oxygen and artificial gravety generated by the rotation of the spacecraft around the longitudinal axis. The ZBTK (Closed Biological-Technical Complex) was developed and ground tested, wth several Russian scientists spending a year inside a sealed environment -- long before the infamous Biosphere experiments in the west.

The ship was to be propelled by the YaERD-2200, an 8.5 ton-thrust electro-plasma engine. With a specific impulse 20 times higher than chemical rocket engines, the craft would be able to travel to Mars or Venus, enter orbit, leave orbit and return to Earth. The thrust was relatively low, and the craft would begin by spirally out from low earth orbit, the crew flying up and getting onboard once the ship was safely above the Van Allen radiation belts.

Ion engines were an idea that appeared earlier than many people realize. Robert Goddard had built experimental ion engines as early as 1916, before the first flight of a liquid-fueled rocket. In 1964, the Soviet Mars probe Zond-2 had tested the first plasma engines in space. Russia developed the technology of Hall-effect acceleration of plasma, still used today for satellite orientation and on the European SMART-1 lunar probe.

The YaERD-2200 engine would have been powered by a 2200 kilowatt nuclear reactor, using thermionic emission to generate electricity directly from incandescent uranium oxide fuel elements. The Russians later did develop smaller thermionic reactors such as Topaz-1, which was orbited and tested in combination with ion engines. The program became controversial after a nuclear satellite reentered the atmosphere and crashed in Canada.

Today, the technology of building large, long-lasting structures in low earth orbit is much better understood. A perminent mobile laboratory, powered by nuclear fission and ion propulsion could be built and used to roam the solar system. But many technical problems remain, including the protection of the crew during solar radiation outbursts.

Recently, the American astronaut Buzz Aldrin has been calling for work to begin on an a modern version of the TMK concept, which he calls the Exploration Module or XM.

1.0 Apples

2010-02-14T20:57:00.000-08:00

Ever notice that floating point numbers are plural? You say "I have 1 apple", but "I have 1.0 apples" (i.e., "one point zero apples").

Megacycles: The Screen Play

2009-10-08T16:31:00.000-07:00

(define Time 0.5)

;
;       sky dome
;
(define SKY (surface BLEND_TURBULENCE SURF_CONSTANT BUMP_FLAT SURF_CONSTANT BUMP_FLAT 0 1))

(define (skyDome) (scale 30 30 30 (move 0 3985 0
 (scale 20 20 20 (shade SKY (rgb 0.1 0.3 0.9) (rgb 0.9 0.9 0.9)
  (scale 0.05 0.05 0.05 (diff
   (scale 4100 4100 4100 (sphere))
   (scale 4000 4000 4000 (sphere))
  ))
 ))
)))


;
; quadric robot with parameterized joins
;

(define (Robot L_SHOULDER L_ELBOW R_SHOULDER R_ELBOW L_HIP L_KNEE R_HIP R_KNEE)
    (bound (union
 (bound (union  ; head and trunk
  (move 0 210 0 (rotate 20 '(0 0 1) (scale 32 48 32 (sphere))))
  (move 0 160 0 (scale 20 40 20 (sphere))) ; neck
  (move 0 120 15 (scale 30 40 55 (sphere))) ; chest and shoulders
  (move 0 120 -15 (scale 30 40 55 (sphere)))
  (move 0 80 0 (scale 30 80 50 (sphere))) ; abdomen and hip
  (move 0 -50 0 (scale 35 35 55 (sphere)))
  (move 0 34 0 (scale 25 25 35 (sphere)))
  (move 0 17 0 (scale 25 25 35 (sphere)))
  (move 0 0 0 (scale 25 25 35 (sphere)))
  (move 0 -17 0 (scale 25 25 35 (sphere)))
 ))

 ; left arm
 (bound (move 0 130 70 (rotate L_SHOULDER '(0 0 1) (union
  ; forearm and hand
  (move 0 -110 0  (rotate L_ELBOW '(0 0 1) (union
   (move 0 0 0 (scale 13 20 13 (sphere)))
   (move 0 -50 0 (scale 12 50 12 (sphere)))
   (move 0 -100 0 (scale 10 10 10 (sphere)))
   (move 0 -120 0  (scale 12 25  6 (sphere)))
  )))
  ; upper arm
  (move 0 -55 0 (scale 23 55 16 (sphere)))
  (move 0 -10 -10 (rotate -35 '(1 0 0) (scale 22 33 22 (sphere))))
 ))))

 ; right arm
 (bound (move 0 130 -70 (scale 1 1 -1 (rotate R_SHOULDER '(0 0 1) (union
  ; forearm and hand
  (move 0 -110 0  (rotate R_ELBOW '(0 0 1) (union
   (move 0 0 0 (scale 13 20 13 (sphere)))
   (move 0 -50 0 (scale 12 50 12 (sphere)))
   (move 0 -100 0 (scale 10 10 10 (sphere)))
   (move 0 -120 0  (scale 12 25  6 (sphere)))
  )))
  ; upper arm
  (move 0 -55 0 (scale 23 55 16 (sphere)))
  (move 0 -10 -10 (rotate -35 '(1 0 0) (scale 22 33 22 (sphere))))
 )))))

 ; left leg
 (bound (move 0 -50 30 (rotate L_HIP '(0 0 1) (union
  (move 0 -160 0 (rotate L_KNEE '(0 0 1) (union ; calf and foot
   (move 0 0 0 (scale 20 20 20 (sphere)))
   (move 0 -75 0 (scale 20 75 20 (sphere))) 
   (move 0 -150 0 (scale 20 12 12 (sphere)))
   (move 20 -160 0 (scale 45 10 20 (sphere)))
  )))
  (move 0 -80 0 (scale 30 80 27 (sphere))) ; thigh
 ))))

 ; right leg
 (bound (move 0 -50 -30 (scale 1 1 -1 (rotate R_HIP '(0 0 1) (union
  (move 0 -160 0 (rotate R_KNEE '(0 0 1) (union ; calf and foot
   (move 0 0 0 (scale 20 20 20 (sphere)))
   (move 0 -75 0 (scale 20 75 20 (sphere))) 
   (move 0 -150 0 (scale 20 12 12 (sphere)))
   (move 20 -160 0 (scale 45 10 20 (sphere)))
  )))
  (move 0 -80 0 (scale 30 80 27 (sphere))) ; thigh
 )))))
    ))
)

;
; robot riding a unicycle
;
(define PI 3.14159265358979323846)
(define RTD 57.29577951308232087721)
(define (S angle)
 (sin (* angle RTD))
)
(define (C angle)
 (cos (* angle RTD))
)
(define (A angle)
 (/ (atan angle) RTD)
)
(define (sqr x)
 (* x x)
)

(define (unicyclist time)
 (let* (
      (s (* PI (- 2 time))) ; pedal angle (0-2 PI)
      (f (* 0.8 (S s)))  ; foot(z)
      (g (* 0.8 (C s)))  ; foot(y)
      (h (- 5.33333 1))  ; height of hip joint
      (l 2.66667)   ; length of thigh (and calf)
      (d (sqrt (+ (sqr (- h g)) (sqr f)))); dist foot to hip
      (v (sqrt (- (sqr l) (/ (sqr d) 4)))); knee-chord dist
      (a (A (* 2 (/ v d)))) ; internal angle
      (k (* -360 (/ a PI))) ; knee angle (with thigh)
      (c (A (/ f (- g h)))) ; external angle
      (j (* 180 (/ (+ a c) PI))) ; hip angle

      (s (+ s PI))  ; pedal angle (1-3 PI)
      (f (* 0.8 (S s)))  ; foot(z)
      (g (* 0.8 (C s)))  ; foot(y)
      (h (- 5.33333 1))  ; height of hip joint
      (l 2.66667)   ; length of thigh (and calf)
      (d (sqrt (+ (sqr (- h g)) (sqr f)))); dist foot to hip
      (v (sqrt (- (sqr l) (/ (sqr d) 4)))); knee-chord dist
      (a (A (* 2 (/ v d)))) ; internal angle
      (n (* -360 (/ a PI))) ; knee angle (with thigh)
      (c (A (/ f (- g h)))) ; external angle
      (m (* 180 (/ (+ a c) PI))) ; hip angle

      (le (+ 15 (* 15 (C (* (+ time 1) PI))))) ; left elbow
      (ls (* 20 (C (* (+ time 1) PI))))  ; left shoulder
      (re (+ 15 (* 15 (C (* time PI))))) ; right elbow
      (rs (* 20 (C (* time PI))))  ; right shoulder
  )
  (move 0 -0.13662 0 (scale 0.5 0.5 0.5 (union
   (move 0 -6.1666667 0 (scale 0.016667 -0.016667 -0.016667
       (rotate 90 '(0 1 0)
    (shade SURF_PLASTIC (rgb 1.5 0.65 .1)
     (Robot ls le rs re j k m n)
    )
       )
   ))
   (move 0 -1 0 (rotate 90 '(0 1 0)
    (scale 1.27324 1.27324 0.1
     (move 0 0 1 (cylinder))
    )
   ))
  )))
 )
)

(define figure (def-prim (unicyclist Time)))
;
; generate peano-curve maze with recursive instancing
; D. P. Mitchell  90/06/09.
;

;
; Unit cell of peano-curve maze is slab with origin at O
; and three figures beginning at R0, R1, and R2.  There are
; three varieties, where R2 goes forward, turns left, or
; turns right.  The final location of R2 will then be F, L,
; or R respectively.  The cycle time is 2 seconds.
;
; -2 2 6 10 14
;  -2 +---------------------------L---+
;     
;   0   O R0 R1 R2 F    ----> Z axis
;     
;   2 +---------------------------R---+
;

(define eF (def-prim
 (bound (union
  (move 0 32 6 (scale 2 32 8 (cube)))
  (move 0 0 2 (velocity 0 0 2 (figure)))
  (move 0 0 6 (velocity 0 0 2 (figure)))
  (move 0 0 10 (velocity 0 0 2 (figure)))
 ))
))

(define eR (def-prim
 (bound (union
  (move 0 32 6 (scale 2 32 8 (cube)))
  (move 0 0 2 (velocity 0 0 2 (figure)))
  (move 0 0 6 (velocity 0 0 2 (figure)))
  (move 2 0 10 (spin 45 '(0 1 0) (move -2 0 0 (figure))))
 ))
))

(define eL (def-prim
 (bound (union
  (move 0 32 6 (scale 2 32 8 (cube)))
  (move 0 0 2 (velocity 0 0 2 (figure)))
  (move 0 0 6 (velocity 0 0 2 (figure)))
  (move -2 0 10 (spin -45 '(0 1 0) (move 2 0 0 (figure))))
 ))
))

;
; first order peano curves are just made out of edges
;
(define (clock1 turn) (def-prim (bound (union
 (eR)
 (move 0 0 12 (rotate 90 '(0 1 0) (eR)))
 (move 12 0 12 (rotate 180 '(0 1 0) (turn)))
))))

(define clock1R (clock1 eR))
(define clock1F (clock1 eF))
(define clock1L (clock1 eL))

(define (counter1 turn) (def-prim (bound (union
 (move 12 0 0 (eL))
 (move 12 0 12 (rotate -90 '(0 1 0) (eL)))
 (move 0 0 12 (rotate -180 '(0 1 0) (turn)))
))))

(define counter1R (counter1 eR))
(define counter1F (counter1 eF))
(define counter1L (counter1 eL))

;
; higher order peano curves are build out of edges and
; lower order curves
;
; six curves are needed at each order, three going clockwise
; and three counterclockwise and the figures turning left, right
; or going straight as they leave the curve.
;
(define (clockWise size quad1 edge1 quad2 edge2 quad3 edge3 quad4)
 (def-prim (bound (union
  (move 0 0 size (rotate 90 '(0 1 0) (quad1)))
  (move 0 0 size (edge1))
  (move 0 0 (+ 12 size) (quad2))
  (move size 0 (+ 12 size) (rotate 90 '(0 1 0) (edge2)))
  (move (+ 12 size) 0 (+ 12 size) (quad3))
  (move (+ 12 size size) 0 (+ 12 size) (rotate 180 '(0 1 0) (edge3)))
  (move (+ 12 size size) 0 0 (rotate -90 '(0 1 0) (quad4)))
 )))
)

(define (counterWise size quad1 edge1 quad2 edge2 quad3 edge3 quad4)
 (def-prim (bound (union
  (move 0 0 size (rotate 90 '(0 1 0) (quad1)))
  (move 0 0 (+ 12 size) (rotate 180 '(0 1 0) (edge1)))
  (move 0 0 (+ 12 size) (quad2))
  (move (+ 12 size) 0 (+ 12 size) (rotate -90 '(0 1 0) (edge2)))
  (move (+ 12 size) 0 (+ 12 size) (quad3))
  (move (+ 12 size size) 0 size (edge3))
  (move (+ 12 size size) 0 0 (rotate -90 '(0 1 0) (quad4)))
 )))
)

(define (oddPeanos size primitives) (let
 (
  (cR (car primitives))
  (cF (car (cdr primitives)))
  (cL (car (cdr (cdr primitives))))
  (ccR (car (cdr (cdr (cdr primitives)))))
  (ccF (car (cdr (cdr (cdr (cdr primitives))))))
  (ccL (car (cdr (cdr (cdr (cdr (cdr primitives)))))))
 )
 (list
  (clockWise size ccF eR cF eF cR eF ccR)
  (clockWise size ccF eR cF eF cR eF ccF)
  (clockWise size ccF eR cF eF cR eF ccL)
  (counterWise size cR eF ccL eF ccF eL cF)
  (counterWise size cF eF ccL eF ccF eL cF)
  (counterWise size cL eF ccL eF ccF eL cF)
 )
))

(define (evenPeanos size primitives) (let
 (
  (cR (car primitives))
  (cF (car (cdr primitives)))
  (cL (car (cdr (cdr primitives))))
  (ccR (car (cdr (cdr (cdr primitives)))))
  (ccF (car (cdr (cdr (cdr (cdr primitives))))))
  (ccL (car (cdr (cdr (cdr (cdr (cdr primitives)))))))
 )
 (list
  (clockWise size ccR eF cL eL cF eR ccR)
  (clockWise size ccR eF cL eL cF eR ccF)
  (clockWise size ccR eF cL eL cF eR ccL)
  (counterWise size cR eL ccF eR ccR eF cL)
  (counterWise size cF eL ccF eR ccR eF cL)
  (counterWise size cL eL ccF eR ccR eF cL)
 )
))

(define (peano n size odd even primitives)
 (if (= n 1)
  ;
  ; return clockwise forward version
  ;
  (let ((curve (car (cdr primitives))))  (curve))
  (peano
   (- n 1)
   (+ 12 size size)
   even odd  ; swap even and odd
   (even size primitives)
  )
 )
)

(define (peanoCurve n)
 (peano n 12 oddPeanos evenPeanos
  (list clock1R clock1F clock1L
        counter1R counter1F counter1L
  )
 )
)

(define (peanoSize n)
 (if (= n 0)
  0
  (+ 12 (* 2 (peanoSize (- n 1))))
 )
)

(define CHECKER (surface MASK_CHECKER SURF_MATTE BUMP_FLAT SURF_MATTE BUMP_FLAT
 0 0))

(globals (rgb 0 0 0) 0.05 0.0)

(render (cine 256 256 1) (union
 (move -100 -4000 -1000 (light 4400))
; (move -4000 -1000 -1000 (light 250))
 (move 6 -14 6 (rotate 45 '(0 1 0) (rotate -10 '(1 0 0) (move 0 0 -50
  (scale 12 12 40 (camera))
 ))))

 (scale 2 2 2
  (move 0 0.125 0 (scale 0.5 0.5 0.5 (peanoCurve 5)))
 )
))

50th Anniversary of First Photos of the Far Side of the Moon

2009-10-06T18:30:00.000-07:00

50 years ago today, Luna-3 took the first photographs of the far side of the Moon in 1959. They were shot on film, developed automatically onboard, and then scanned and transmitted by radio.

http://www.mentallandscape.com/L_Luna.htm

A Nobel Prize for Sputnik

2009-09-06T21:27:00.000-07:00

According to some accounts, the Nobel Committee approached Nikita Khrushchev after the launch of Sputnik-1. But the Russian government would not reveal the name of their "chief designer", Sergei Korolev. So the scientific achievement that began the space age went unacknowledged.

Nobel prizes can only be given to living persons, but there is still an opportunity to award the Prize in Physics to Boris Evseevich Chertok. Chertok, who is 97 years old now, was a major contributor to the development of the R-7 rocket and the launch of Sputnik. He was one of Korolev's right hand men, the division head of rocket control systems.

Electric Cars Get About 60-70 mpg

2009-08-13T18:37:00.000-07:00

GM has announced the Chevy Volt, getting 230 miles per gallon, and Nissan has announced an electric car they claim gets 367 mpg. I'm not sure how they arrive at those numbers, but let's try to estimate a more meaningful mpg value.

The Nissan goes 100 miles on a 24 kilowatt-hour battery charge. That means 4.2 miles per kwh. A friend of mine owns a Tesla Roadster, and he says he consistantly gets 240 wH/mile, which also translates to 4.2 miles per kilowatt-hour. That energy comes from power plants, which could theoretically burn gasoline. A gallon of gasoline yields about 36.6 kilowatt hours of energy when burned, but the engine in conventional cars only used about 20% of that energy. Power plants are about 45%efficient, because they use turbine engines. Furthermore, there is about a 7 percent average loss of power in the transformers and power lines used to deliver electricity to your home.

There is also charge-discharge efficiency of batteries and the efficiency of electric motors, but that is already factored into our direct measurement of 4.2 khw/mile. So assuming 4.2 kwh/mile, and 36.6 khw/gallon, and 42% efficiency, I get 64 miles per gallon. Let's say 60 to 70, because this is not a precise calculation.

That's good, but not vastly better than a hybrid. What is really interesting about the electric car is that electricity can come from sustainable sources like wind and solar energy. And in the short term, it can come from coal and natural gas, which America has in great abundance.

The Apollo Landing Sites Pose a Danger to NASA's New Orbiter

2009-07-21T23:23:00.000-07:00

While conspiracy nuts debate the reality of the Apollo landings, scientists must deal with some practical consequences of what astronauts put on the Moon. For the new Lunar Orbiter Laser Altimeter (LOLA), this means dodging the retro reflective mirrors mounted by astronauts at some of the landing sites.

The Apollo astronauts installed arrays of prisms at some landing sites, designed to bounce laser light directly back in the direction it came from. They reflect a signal, proportional to 1/R**2 instead of 1/R**4, where R is distance. These devices are still in use today, to monitor exact motion of the Moon and test physical theories.

The LRO carries a highly accurate laser altimeter, similar to the one installed on recent American Mars orbiters. It occured to me that this instrument might also verify the existance of the Apollo landing sites (as the LRO cameras have already done), but then it also occured to me that it might return a laser signal so strong that it could damage the instrument.

I wrote to David E. Smith at Goddard, the principal investigator for LOLA, to ask about this. He replied that this was most definitely a problem, and the LOLA instrument switches off when the orbiter passes over Apollo sites. If by small chance, the beam did strike the retro reflector, the light bounced back would be 1000 times the detector damage threshold!

The Russians have also been helpful in giving the LOLA team the best known locations for the two Lunokhod rovers, which also have laser retro reflectors mounted on them. Lunokhod-2 has been located precisely and is routinely probed by lasers from Earth. Lunokhod-1 has never been found by laser, and it is not known for certain if its reflector is deployed. Seen in the photo above, we can see the relfector (extended to the left) bouncing back the light from the camera's flash.

How Many Memories Do People Have?

2009-06-02T08:00:00.000-07:00

How many events, stories and facts do people really remember? I decided to do a very crude experiment. From a complete list of vocabulary words, I generated sets of word triples (Noun, Verb, Noun) such as:

1 clarity consider sonnet
2 letterman propose tapdance
3 assignment deduce senate
4 virtuoso weaken ferment
5 controversy jeopardize globe
6 dialysis recur rooftop
7 dislocation admit portal
8 swirl decrease bough
9 dolphin install compatriot
10 gust beware extrapolation

There are about 200 billion possible triples. I seem to be able to assign an obvious word triple to almost anything I remember. But in a random set of 1000 triples, I didn't see any that obviously described a memory. I decided to cut back the experiment and just generate pairs of nouns:

1 lunch clarity
2 fist sonnet
3 letterman gamble
4 tapdance assignment
5 ounce senate
6 extrapolation mast
7 ferment controversy
8 yip globe
9 dialysis artisan
10 rooftop dislocation

There are 100 million possible pairs from my vocabulary set, and I'm looking for clear associations with memories, like "kennedy assassination" or "birthday party". Out of a random sample, about 2 percent could be associated in such an obvious way with a memory. If every memory could be assigned a fairly obvious word pair, then this implies that I only have about 2 million memories.

That's a surprisingly small number. I'm pretty skeptical about this experiment, and I'm sure we can find countless flaws in the whole concept of it. But it is amusing and suggests a contrary notion that the human mind might be far more limited that we like to believe (and we all know how much I enjoy contrary notions).

One obvious flaw is that meaningful word pairs might only number in the millions, but could refer to hundreds of different memories. So I tend to conclude that people have somewhere from 1 to 100 million memories.

Another approach to estimation of long-term memory capacity is to note that people only live for about 30,000 days. How many events per day really stand out enough for people to remember them permanently? That makes it easier for me to believe that people only have on the order of a million memories.

-------

PS. I haven't been posting a lot to my blog, because I've been putting my thoughts on Facebook notes. (http://www.facebook.com/profile.php?id=506882584). Folks are welcome to send an add request, but I can't guarantee I will accept requests from strangers, unless they have a real Facebook page that let's me know who they are.

The Economy and Energy

2008-10-10T05:20:00.000-07:00

I. Who's Fault Is This Mess?

I believe in free markets. As a computer scientist, I've seen how the principles of capitalism have led to astonishing new inventions and positive economic activity just in my own field. As an historian of the Soviet space program, I also see just how poorly socialism functions in comparison.

In our current economic problem, there is plenty of blame to spread around. I personally see two places where the market was subverted:

1. Pressure from liberal government policies to give loans to people who couldn't afford them.

2. Dishonest labeling of the risk and quality of some mortgage-based bonds.

I'm not adverse to regulating the amount of leveraging in the market, but I can't help but think that people would never have risked so much if they had not thought they were buying "A" rated securities. Civil and criminal liability needs to be applied to those responsible for that.

II. Fear Mongering and Political Opportunism

Crisis brings out the best and worst in people. The mainstream media has contributed to the problem by flat out telling people to dump their stock. If you sell your stock now, you turn unrealized loss into actual loss. If the meat puppets on the network news keep yammering about bad banks, they could cause a run on the banks, and then of course they really would fail.

Talk of the Great Depression are popular now, but in fact there is no comparison: Depression Fears Overblown

Crisis also creates opportunity for would-be political mass movements. On the far left we hear talk of socialism and the failure of capitalism. On the far right, we hear populist nonsense about the bailout. Just the kind of hysterical actions that are bad for America now.

III. Fundamentals - Education and Energy

Adam Smith taught us the most important thing we can know about economics: the wealth of a nation is created by human productivity, not by "treasure". Compare a resource-poor nation like Japan to a resource-rich nation like Saudi Arabia or Venezuela. Where would you rather live? Nations that are truly wealthy have invested in their people, educating them to be productive and self sufficient. America does a fair job of this, but should do better.

Both candidates of said something to this effect, probably because they have been talking to T. Boone Pickens: we could revitalize our nation’s economy by embarking in a project to rebuild our energy infrastructure. Here is why I think that is a great idea:

1. Energy is crucial to a modern economy because it amplifies human productivity. We cannot allow ourselves to ride the downslide of global petroleum production.

2. New energy sources will free of us from dependence on hostile foreign petroleum suppliers.

3. Building a new infrastructure will create jobs and build long-term economic opportunities in the same way that the space program and the computer revolution did.

4. More young people will be encouraged to learn science and engineering.

5. I believe we can create vast amounts of cheap electrical power, but it may have new characteristics. Electricity might be cheap when the wind is blowing in northern Texas, and expensive during week-long lulls. People and the market can adjust. It creates a market incentive to store energy when its cheap and sell it when its expensive, which will level the pricing to some extent.

6. The free market can solve the energy-storage problem, but nation action is needed to upgrade our electrical grid so we can move more power over greater distances. The Soviets did this in the 1930s, we can certainly do it in America today. But it requires the national will to override eco-extremists and opponents of eminent domain.

Telegenomic Colonization

2008-09-27T23:17:00.001-07:00

Can man colonize nearby stars? Most of the discussions of this problem seem to assume non-existent or practically impossible physics -- warp drives, antimatter power sources, giant lasers that defy the law of diffraction. Is there a way to do it with technology that could actually be developed? I think so:

Step 1: Super-Telescope Survey

Build a multiple-aperture telescope in space, able to image and spectroanalyze the nearest extrasolar planets. The law of diffraction dictates that the synthetic aperture must be hundreds of kilometers or perhaps thousands. This is expensive but far cheaper than sending probes to many nearby stars.

Step 2: Robotic Probes

If suitable planets are found, send unmanned probes using fission-powered ion drives with relativistic exhaust velocities. They must be big enough to reach the star and decelerate into planetary orbit. They will be expensive and take centuries to reach their destinations, travelling at 1 or 2 percent of the speed of light. Use somewhat more efficient fusion power, if it is developed.

Step 3: Telegenomic Transmission

Once in position, the probes can receive radio transmission of human genomes of volunteers (and/or carry some onboard in digital storage). Remote growth of clones from synthesized DNA would need to be developed. Remote raising of the children would also be necessary -- these would be clones of terrestrial hosts, but would of course not have the host's memory or personality.

Radio transmission of genomes (telegenomic) allows unlimited colonization without the extreme expense of carrying human payloads. I believe it is a practical impossibility to carry living beings between stars. I also do not believe any power source beyond nuclear fission or fusion (tenths of a percent mass-conversion efficient) will ever be possible, which places severe limits on intersteller travel.

Credit Crisis 101

2008-09-23T11:13:00.000-07:00

A friend at Morgan Stanley recommended this article written in March at the New York Times. It briefly discusses some of the problems caused by unregulated leveraged buying of mortgages. Basically, this is how the conservatives screwed up:

NY Times

Another article that has been widely discussed, from the Washington Post, explores how the liberals screwed up, by pushing banks into giving home loans to the underprivileged:

Washington Post

Plenty of blame to go around...

Citizens of the Stratosphere

2008-08-09T15:19:00.000-07:00

In 1934 Sergei Korolev, future leader of the Soviet space program, published his first book: Rocket Flight to the Stratosphere. While a handful of people were talking about flight in outer space then, considerably more attention was being focused on the conquest of the upper atmosphere. An international race commenced with many of the characteristics of the space race decades later.

Crocco's Refrigerated Supersonic Cabin
The Italian pioneer of aviation, General G. Arturo Crocco had been a major inspiration to Korolev and others, when his writings about Superaviation in the 1920s. Crocco pointed out the tremendous value of flying at extreme altitude and speed, but in 1926 he had proved that propellers couldn't function in these conditions. Inspired by the new theory of jet engines developed by Soviet scientist Boris Stechkin, Crocco wrote an influential paper in 1931 advocating the use of ramjet engines to fly through the stratosphere at "super acoustic" velocity. At such speeds, the pilot's cabin would have to be refrigerated to counteract the heat of friction with the atmosphere.

Soviet ramjet engine, GIRD-04
In 1933, Korolev's jet propulsion research group in Moscow began the world's first work on ramjet technology. GIRD-04 was a hydrogen powered engine, tested in a supersonic wind tunnel. History of this work has been largely eclipsed by GIRD-09, Korolev's first rocket, launched later that year.

Soviet Balloon "Osoaviakhim-1"
Interest in the upper atmosphere soon triggered a dangerous international contest to reach the stratosphere in hydrogen balloons. One of the first to perish was the American explorer Hawthorne Grey, who reached an altitude of 12.9 kilometers. On the way back to Earth, his oxygen supply ran out and he suffocated.

In 1933, the balloon "USSR-1" reached 19 kilometers, performing cosmic-ray experiments and taking samples of the atmosphere for chemical analysis. The airtight nacelle carried liquid oxygen tanks and chemical scrubbers to remove carbon dioxide and excess water vapor.

A few months later, in January 1934, the balloon "Osoaviakhim-1" was launched. Osoaviakhim was a paramilitary club that sponsored events ranging from parachute-jumping clubs to the funding of Korolev's research lab. Its confident pilots, Fedoseyenko, Vasenko and Usyskin, boasted that they would be "citizens of the stratosphere". Osoaviachim-1 reached the record breaking altitude of 22 kilometers, but during its descent an unexpected cooling of the gas in the balloon caused it to contract and trigger an uncontrolled descent. Trying to remove the 24 bolts holding the hatch closed, the young aeronauts died when the capsule struck ground.

In 1939, the stratospheric balloon "Konsomol" was launched by the Soviet Academy of Sciences. Its commander, A.A. Fomin sent a radio telegram to Stalin from an altitude of 16.8 kilometers. During his descent, at an altitude of 9 km, the hydrogen balloon caught fire and the capsule began to fall. Fomin quickly threw a switch to disconnect the nacelle from the flaming balloon, but when he pulled the parachute ring, it failed to deploy. At 6 km, they got the hatch open, then waited breathing from their oxygen supply while the capsule plummeted. At 4 km they could safely jump with personal parachutes.

1934 All-Union Conference on the Study of the Stratosphere
In 1934, a major conference was held on the study of the stratosphere. After an open address on the mastery of the stratosphere, by academician S.I. Vavilov, 79 scientists presented papers on the structure of the atmosphere, high altitude photography, spectroscopic studies of the far ultraviolet wavelengths blocked by the dense atmosphere, cosmic rays, biomedical problems of high altitude flight, and the technology of rockets and jet engines.

For Sergei Korolev, the conference was an important opportunity to promote his idea of boost-glide rocket planes, which has recently been cancelled by his new boss. In his report, he described a rocket-powered glider that would reach an altitude of 23 kilometers, and then glide a distance of 280 km. Shortly after, he was able to resume work on the project.

The published proceedings were 927 pages long, but when they were translated into English in 1938 the size had dropped to 307 pages. Only 39 authors were presented. In the intervening years, most of the missing authors had been executed or imprisoned during Stalin's political purges.

Eric Hoffer

2008-08-02T10:45:00.000-07:00

In 1951, the American philosopher Eric Hoffer wrote The True Believer. This book discussed the phenomenon of the politcial mass movement, which one can argue, is the cause of a great deal of historical evil and suffering. While blaming the charasmatic and dishonest people who start such movements, he placed the majority of responsibility on a certain type of individual who becomes a zealot.

Hoffer considered large mass movements like Fascism, Communism and radical Islam. But movements can be smaller and thankfully less damaging, revolving around smaller issues like animal rights, software, conspiracy theories, etc.

I ran across a small collection of quotations from that work, which I wanted to post here:

"Passionate hatred can give meaning and purpose to an empty life. Thus people haunted by the purposelessness of their lives try to find a new content not only by dedicating themselves to a holy cause but also by nursing a fanatical grievance. A mass movement offers them unlimited opportunities for both."

"In an affluent society, the alienated who clamor for power are largely untalented people who cannot make use of the unprecedented opportunities for self-realization, and cannot escape the confrontation with an ineffectual self."

"Such persons sooner or later turn their backs on an individual existence and strive to acquire a sense of worth and a purpose by an identification with a holy cause, a leader, or a movement. The faith and pride they derive from such an identification serve them as substitutes for the unattainable self-confidence and self-respect."

"When watching men of power in action it must be always kept in mind that, whether they know it or not, their main purpose is the elimination or neutralization of the independent individual- the independent voter, consumer, worker, owner, thinker..."

"A doctrine insulates the devout not only against the realities around them but also against their own selves. The fanatical believer is not conscious of his envy, malice, pettiness and dishonesty. There is a wall of words between his consciousness and his real self."

The Universe for Dummies

2008-07-21T09:51:00.000-07:00

What has happened to the art of making great documentaries about science? I'm thinking about amazing programs like "The Ascent of Man" by Jacob Bronowski, "Cosmos" by Carl Sagan or even the more recent "Planets" by the BBC? The first two really communicated the history and motivation and spirit of science, and The Planets at least communicated a coherent history of planetary exploration.

I recently bought the History Channel's series "The Universe", thinking I might send a copy to my niece's kids. I didn't bother, because it was absolutely terrible. The program was a series of flashy images and factoids, many of them simply incorrect. It failed to interview highly prominant scientists who were engagned in space missions. The episode on Venus, for example, didn't even discuss any of the spacecraft sent to Venus or describe their experiements or interview the men who sent them.

These modern science programs simply fail to communicate the spirit of science. What questions are asked, how are they considered and answered by experiments and discourse, how did people make mistakes and then correct them? They fail to teach the scientific method. They fail to show how real scientists are engaged in a meaningful life that gives them pleasure.

Is it any wonder that so many people today cannot differentiate science from pseudo-science? A program like "The Universe" is not not much different in structure from a quack documentary like "The Secret" or a program about UFOs.

Science is being presented as "Gee whiz! Don't you wish you were smart like these people?" instead of something that young viewers might actually want to do when they grow up.

PS. If you haven't seen "The Ascent of Man", consider renting it and watching it.

Whole-Plant Biofuel

2008-06-29T12:24:00.000-07:00

As I calculated in a previous blog entry, there is no hope that biodiesel can replace petroleum. Even if we starved and planted all our land with canola, we could only make about 15 percent of the oil we use.

Photosynthesis is not very efficient, 1 percent, maybe 2 percent for amazing plants like sugar cane or corn. Most of that energy goes into the cellulose in the stems and leaves, so any scheme that only uses a tiny portion of the plant -- oil seeds or starch from corn kernels -- is taking about 1 percent of that 1 percent. That's a lose.

Some types of algae have high percentage yields of oil, but aquaculture cannot be applied to a significant percentage of our 400 million acres of arable land. Makes for some nice journal papers and research grants, but I don't think it will be practically useful.

Where biofuel has worked, people have burned the whole plant for fuel. In Brazil, ethanol is made from sugar cane, but more importantly, the husks are burned to fuel the distillation process. In America, propane is burned, which is just crazy. This is one reason why Brazil gets a 900 percent return on energy from ethanol, and America gets about 100 percent return (about the same energy out as put in). Sorry to be political here, but I believe the US corn ethanol program is a boondoggle promoted by the corn lobby. It is putting pressure on food prices and not solving our energy problem.

Another nice example of biofuel from whole plants is the Florida Crystals operation. They run a 75 megawatt power plant fueled by cane husk and yard waste. This is enough electricity to run their factory and sell power to 40,000 nearby homes. This is not a university experiment, it is a real company that makes a product and a profit, and they are using biofuel.

http://www.floridacrystals.com/index.cfm?fuseaction=pages.renewableenergy&x=7040543

As with a lot of alternative energy, it is easy to run a large stationary power plant. I honestly do not expect the cost of electricty in the USA to increase much. Coal powered plants can also augment their fuel with biomass. I'm more concerned about applications that need portable energy of high density -- tractors and airplanes in particular. Commutor cars can probably be electric, but I doubt if farm machinery, working hard all day, can be operated off batteries. As we enter peak oil, whenever that is, the production of food will be the most important operation to come under pressure.

Good News

2008-06-26T09:56:00.000-07:00

I don't watch TV or get a newspaper. Instead I look at the web every morning, usually checking four sites for news.

First, and don't ask me why, I look at MSNBC.com. It's completely crap. I know it's complete crap. But hey, what if Britney Spears got arrested again today? At least I have stopped looking at their science and technology section, which is largely made up of garbage from www.livescience.com -- oh don't get me started about them. OK, I'm going to make an effort to NOT look at MSNBC or CNN anymore.

Next, I look at the BBC's site: http://news.bbc.co.uk/. This is a good source of international news, but it has gone downhill in quality in the last few years. There is a lot of POV and crusading journalists to deal with, and pretty much everything that happens now has something to do with global warming. But nevertheless, it is light-years beyond MSNBC or CNN.

Now it's time for real news. And after looking at the first two sites, I am always amazed when I check the Christian Science Monitor's webpage: http://www.csmonitor.com/

Today, I see India is having a crisis because it agreed to buy nuclear fuel from the USA, but the communists might bring down the government because they don't care about nuclear energy and don't want ties with the US. There was a thoughtful article about the relationship between rising gas prices and the low value of the dollar. Is raising the dollar a good idea? Maybe not. In general, this site makes MSNBC and BBC both look garish and amateurish.

Finally, as a computer professional, I naturally read The Register: http://www.theregister.co.uk/. Not to be confused with the other tech site The Inquirer, which is pretty junky. The Register has several good journalists with different points of view, and for the most part they seem to be honest. I often get pissed off at them, but then so do the people whose eyes turn into rotating spirals when they talk about Linux.

Some Arithmetic About Alternative Energy

2008-06-14T21:30:00.000-07:00

Here are some back of the envelope calculations about alternative energy.
1. Biodiesel: Canola (rapeseed) yields about 122 gallons of oil per acre. If the USA planted all of its arable land, 407 million acres, with canola, we could produce 188 billion liters of oil per year. The bad news, we consume 1207 billion liters of petroleum per year. Oil seeds can never solve our energy problem, and ethanol from corn is even worse.
2. ANWR: USGS suggests there is likely 10.4 billion barrels of oil in ANWR and the local undersea shelf. The USA consumes 7.6 billion barrels per year. We should drill in ANWR, but it's not going to have a huge impact on our energy problem.
3. Nuclear: The Department of Energy estimates US Uranium reserves at 1155 million pounds (yellow cake) at $50 per pound mining and refining cost or less. Our 103 nuclear power plants consume about 40 million pounds per year of this fuel. That is 29 year supply of fuel, plus reserves. Unless we invest massively and quickly in breeder reactors, we will run out of cheap nuclear fuel before we run out of cheap petroleum.
4. Solar power: With 10% efficiency, one can optimistically expect an average of 30 watts per day per meter square from conventional photovoltaic panels. To supply the US average energy usage of 3.3 terawatts, we would need 110,000 square kilometers of solar panels, about 1.2 percent of the total land area of the USA. Anyone want to estimate the cost?

Alternative Energy in Germany

2008-06-12T10:51:00.000-07:00

Energy is a major concern of mine. I fear that peaked oil production, rising prices and falling supply could cause a terrible decline in standard of living and general human happiness in the world, and I am frustrated by how counter productive the American far right and far left have been in this area.

Recently I spent 12 days in southern Germany with some family and friends. I was surprised to see a massive, sensible committment to alternative energy. Now I'm a bit skeptical about windmills, although I see fields of them here and there in the USA. But this one was unbelievably huge, towering over the Black Forest near Oberprechtal:

But I was more impressed by the solar panels. I saw them everywhere, on the roofs of houses and barns. Checking on the website of the Bundesverband Solarindustrie, I was not surprised to read that in 2007, peak solar energy production in Germany was 842 megawatts (Germany's total electrical generating capacity is over 100 gigawatts). Our friends in Oberprechtal explained that the government gives out loans for the installation of these panels, and then you start selling power back to the national grid.

The other major effort I witnessed was the production of canola (rapeseed) for biodiesel. Germany is not the land of hippie vegetarians, I assure you. They eat meat, possibly even more than Americans do. We noticed a conspicuous lack of row crops and a vast amount of pastureland and cows, but we also saw yellow fields of canola everywhere.

Canola-based biodiesel is organized by Union zur Foerderung von Oel und Protienpflanzen. They operate their own pumping stations, since oil companies have refused to cooperate with them. In 2006, Germany produced 2 billion liters of biodiesel fuel (Germany consumes 150 billion liters of petroleum per year, as a comparison). Coincidently, on the first leg of my planefligth to Germany, I sat next to a research scientist from Grand Forks, who worked on biodiesel. He had talked about Canola, and predicted that this crop would soon make the Dakotas, Wyoming, Montana and others very rich energy-producing states.

What I saw in Germany is the product of the practical efforts of their Green movement, which stands in stark constrast with America. Obviously, we have folks on the far right who think the Earth is 6000 years old and oil is continuously generated abiotically. But I also blame the left. The American so-called green movement is subverted by leftists who have not acted practially to solve problems of alternative energy production the way the Germans have done, because they are too interested in attacking capitalism. In Germany, the socialists and Greens have their own parties and generally stay in their own lanes. We also are suffering from the very damaging power of the US corn lobby. Ethanol from corn consumes almost the same amount of energy to produce as it yields when burned, while biodiesel from Canola yields a 300% to 400% energy profit.

I'd like to see a serious effort made in the USA, comperable to the Apollo program or the Marshall Plan, to make American energy independant with a long-term-sustainable energy economy. Without energy to amplify human labor, we will not be able to maintain a happy comfortable standard of living or even be able to feed our own population adequately.

Mom's Apple Pie

2007-12-27T12:49:00.000-08:00

Since the mid 1980s, I've kept a set of lab notebooks where I take notes about books I'm studying or problems I'm working on. On January 7, 1989, I was visiting my parents in Minnesota and I took a page of notes about how my Mother makes apple pie.
The story goes that when they were first married, my Dad asked Mom to make pies. She was not particularly good at it, and one time she burned a pie just before company was to arrive. In a panic, she put the burned pie on their bed to hide it. The friends discovered it though and thought it was pretty amusing.
Finally, she asked her cousin Maxine, who was a great cook, to teach her how to do it. She became a master of pie, cake and cookie baking as time went on, much to the enjoyment of me and my brothers. Talking to her later, my Mom said that many of these recipes were inspired by the Spry cookbook, made by an early manufacturer of vegetable shortening. Older country recipes use lard as shortening, which gives a greasy and somewhat burnt-tasting crust that I don't like.

Crust:
3 cups flour
1 cup vegetable shortening (Crisco)
1 tsp salt
Cut together thoroughly with a knife and then mix with: 1/3 cup cold water.

Rolling:
divide dough into two portions for upper and lower crust. Form into 0.5" x 5" disks, then use roller and pastry cloth to flatten into 1/8" sheets. Put lower crust into Pyrex glass pie pan and allow to relax into place.

Apples:
Large Granny Smith are good. Avoid sweet red apples, which will turn to mush. Quarter, core (never let pieces of apple core get in a pie), peel and cut up into small slices with paring knife. Pile apples in the pie pan, pour one cup of sugar over them, light sprinkle of salt, cinnamon and half a dozen chunks of butter.

Top Crust:
Water around edge to fuse top crust to bottom. Cut some small steam vents (you can make a dashed outline of an apple with leaves or the letter "A"). Brush top with milk before baking.

Bake:
Bake for one hour at 400 F next to the bottom row in the oven. Put Pyrex pan on a metal pie ring to catch possible boil over.

Mary Mitchell (1918 - 2007)

Biography V: The Ivory Tower

2007-12-06T21:24:00.000-08:00

In 1991, I took a leave of absence to attend Princeton University and work on a PhD in Computer Science. A respected colleague, Pat Hanrahan, had recently left Pixar and joined the faculty at Princeton. He invited me to come and do research at Princeton and get another degree while I'm at it.

That year, Pat brought in three students, Craig Kolb, Peter Schröder, and myself. We shared a big corner office on the fourth floor, with Pat just down the hall. It was quite a fun crew, Craig was the author of Rayshade, a powerful public domain ray tracer, and Peter had just spent a couple years at the MIT Media Lab. Peter is a remarkably intelligent and disciplined person, and he completed a PhD in only three years.

Graduate school is a different game from getting a bachelor's degree in college. A Master's degree usually finishes up the "book learning" phase, with classes, homework and exams in advanced topics. A Doctorate degree is about learning to read and write journal papers, getting to know the actual people in a field, and learning the scientific (and social) process of doing research. A student's PhD thesis is an extended publication taking years to complete, written under the supervision of an advisor -- a journal publication with training wheels.

I recommend getting a Master's degree, and getting through the PhD candidacy. It's a a total immersion in computer science, and while not very pleasant I have to say, it was a good learning experience. It's a little unusual to return to graduate school at my age, as an established researcher in a field. But I wanted to round out my knowledge, since I was a specialist and had been trained in another field (physics). In some circles, a PhD is necessary for respect, regardless of whatever publications or accomplishments. Industry is more of a meritocracy though, and Craig and I ultimately both returned to that world and never had time to finish our theses.

That November of 1991, I had an idea. I walked into Pat's office and told him that I knew how to render caustics. Caustics are when wavefronts of light fold into singularities, such as the bright cardioid curve you see inside an empty coffee cup when light shines into it. For various reasons, this was something known rendering and shading algorithms could not calculate. Two tricks were needed to do caustics, interval arithmetic optimization, and wavefront curvature. Pat's immediate response was, "Let's go to the Geometry Center in Minneapolis and work on this without distraction, so we can send a paper to SIGGRAPH!"

The deadline for a paper submission was only about a month away, and we had to write a completely new rendering system based on second order differential geometry, and implicit surfaces that could be evaluated in several different arithmetic systems (real numbers, intervals, and automatic-differentiation pairs). We got to Minneapolis, and they had just received 3 feet of snow, then the temperature dropped to 0° F. We froze our asses off that week, walking to and from the center, sometimes in howling winds and blowing snow.

One of the world's foremost mathematicians, Bill Thurston, was there at the center too, so our little group had some amazing dinners and conversations. We described what we were doing with caustic reflections, "It's unfortunately that we can only do this for mirror smooth surfaces". Thurston replied that it could be generalized to rough surfaces, and told us how, but in mathematical terms that were completely over our heads. Pat and I still wonder what he was trying to tell us. One day there was a fire drill at the center. While we were standing outside, I asked Thurston a question about manifolds, and he picked up a stick and drew some diagrams in the side of a snowbank. I thought of Archimedes doing geometry in the sand.

A few months later, I stopped by Pat's office. He had a sheepish expression on his face, like a boy who'd just done something mischievious. "I just won an Academy Award.", he said. Pat was one of the primary inventors of the RenderMan system at Pixar, used in their movies and for many special effects in other films, and its development team had won a technical Oscar. The CS department was greatly surprised and pleased.

Why The PC Should Not Go Away

2007-11-05T10:05:00.000-08:00

There is a standard news article that gets trotted out every month or so: "Is the PC era waning?". Maybe, maybe not, it's something that has been predicted for a decade. But the end of the personal computer (Apple or Windows) would be a bad thing for almost everyone except a few wealthy special interests.

The PC has transformed society, empowered people and businesses and generated enormous wealth. Having lived through the era of the multi-million-dollar mainframe and the $100,000 workstation, I never take my PC for granted. The massive PC market, with its economy of scale, has driven innovation in hardware and software that would have been unimaginable 20 years ago. The $200 video card in my computer does more than the SGI workstation I had at Princeton University, which cost as much as a small house. The Windows operating system has a level of technical sophistication that computer scientists like myself could not have imagined when we were working on UNIX in the 1980s.

There are two alternatives to the PC that various factions would like to see replace it. Let's consider them briefly:

One is the thin client. This is the idea that you own a cheap device that has just enough smarts in it to control a screen and a keyboard and connect to the internet. Your data and computing happens remotely, in a server center owned by Google or IBM or Oracle or someone of that ilk. I'm old enough to remember timesharing. In grad school, if you were at the bottom of the pecking order, you had an X-Terminal on your desk. These were UNIX thin clients that connected to our DEC mainframe, and everyone hated them with a passion. Because so many people were sharing the same server, there was a never-ending hassle over disk quotas and space. And if a few people decided to do some number crunching, say goodbye to your performance. The PC gives the user control. Your data is there beside your desk. The computing power is there for you to use when you want it.

Another alternative is the appliance, like game consoles or mobile phones. The problem there is that these are closed devices. If the PC was replaced by the Play Station, then SONY or someone like them would have total control over software development.

Unlike the Playstation, the Apple and Windows PC are openly programable. If you have a new idea for a program that people can use, get a free copy of Microsoft Visual Studio Express, write the program, and sell it. Microsoft bends over backwards to help you do this, because it increases the value of their platform. For a few hundred dollars, you can get a better version of VS, sample code, documentation, development kits, etc. But if you have an idea for a new Playstation game, you need to get SONY's permission to develop and deploy it. Both the appliance and the thin-client model concentrate control and ownership of software development in a few hands.

Given the astounding success of the computer hardware and software industry, I'm always surprised by how many people are eager to jump in and radically change it. They're ready to shift all the power and money to the server industry. Or they're ready to see the PC replaced with a closed non-programable console. Or they're ready to pull the rug out from under the economics of the software industry by taking programmers' property rights away from them. And of course, any of these things could happen, because sometimes we can't stop ourselves from ruining a good thing.

The End Is Not Nigh

2007-10-02T18:39:00.000-07:00

It's a popular notion, in almost every generation, that the world is heading toward disaster. The idea appeals to the religious right, some of whom look forward to the apocolypse, and it appeals to the far left, because they see it as a justification for revolution. And certainly in every time there have been things happening that are unwelcomed and unfortunate.

But in many respects, the world has been getting better. We think of the last century, with two world wars, as a period of terrible violence. But anthropologists and historians can show that we are actually living in the most peaceful time in the history of the human species. Steven Pinker describes this well in his recent talk at the TED conference:

The Myth of Violence

Pinker shows that the idea that early man lived in peace and harmony is completely false. Hunter-gatherer societies had staggering homicide rates. The chances of a man dying by murder range from 15 to 60 percent in all existing primitive societies that can still be studied (in Amazonia and New Guinea). Even the famous ice man found in a Swiss glacier died from an arrow in his back. The murder rate during the middle ages in Europe was documented and was about 100 times what it is in Western Europe today.

And what about poverty? Swedish professor Hans Rosling demonstrates (with a remarkable graphical presentation of statistics) that our conception of the "Third World" has become outdated. In the last few decades, the standard of living throughout most of the world has improved radically. See his TED talk here:

Debunking third-world myths

What has made the world get better, particularly over the last couple centuries? Largely it appears to be the action of practial people -- The Englightenment, Democracy, Science, Captialism have help mankind throw off the yoke of dictatorship and mysticism.

The philosopher Eric Hoffer discussed this in his famous book "The True Believer".

The True Believer

Practical people make the world better, because they are focused on living a better life and taking care of their families and friends. Ideological and zealous people make the world worse and cause human suffering, because they are focused on power, control and the rejection of social systems that elevate the status of practical people. Ironically, people who have tried to better themselves have often done more than people who have tried to lead revolutions in the name of altruism and spirituality.

A friend of mine recently saw a bumber sticker that expresses the idea concisely:

The End is not Nigh. Balance the budget!.

Trackball

2007-08-14T17:40:00.001-07:00

If you've ever had trouble with tendinitis, as many programmers and PC gamers do, one of the best things you can do is replace the mouse with a trackball. It takes a little practice to get used to it, but it's actually much faster than a mouse.
Alas, one of the best trackballs ever made, the Microsoft Trackball Explorer, is no longer in production. I see them selling for $130 on eBay now.

If you have an old one, it may seem sticky. That's easily fixed. First, periodically you should blow or scrape the lint out of the small metal bearings that the red ball rests on.
To keep the trackball working perfectly, occasionally cover the ball with a very very tiny amount of vasoline. The ball should turn for one or two seconds when you spin it.

Who Dominates Space?

2007-08-04T11:23:00.000-07:00

If you look at how much nations spend on space, you might get the impression that America continues to dominate the exploration of outer space:


NASA                  - $16.6 billion
US DoD Space          - $22.5 billion
European Space Agency - $3.5 billion
Russian Space Agency  - $1.1 billion
Chinese Space Budget  - $1.35 billion

But it is also interesting too look at a snapshot of actualy activity. I looked up all the missions launched into space in the year 2006 and catagorized them by type of mission, launch vehicle:


Deep Space:
-----------
New Horizon        - Atlas V
Stereo A & B       - Delta II
 
Geosynchronous Satellites:
--------------------------
Hot Bird 7A & Spainsat   - Ariane 5
Satmex 6 & Thaicom 5     - Ariane 5
JCAT 3A & Syracuse 3B    - Ariane 5
WildBlue 1 & AMC 18      - Ariane 5
DirectTV 9S & Optus D1   - Ariane 5
Astra 1KR                - Atlas V
Zhongxign 22A            - Chang Zheng 3A
Xinnuo 2                 - Chang Zheng 3B
MITEX                    - Delta II
GOES 13                  - Delta IV
Insat                    - GSLV (Indian)    FAILED
Kiku-8                   - H-IIA
Arabsat 4B               - Proton
Measat 3                 - Proton
Arabsat 4A               - Proton           FAILED
Hotbird 8                - Proton
Kazsat                   - Proton
Echostar 10              - Zenit Sea Launch
JCSAT 9                  - Zenit Sea Launch
Galaxy 16                - Zenit Sea Launch
Koreasat 5               - Zenit Sea Launch
XM Radio 4               - Zenit Sea Launch
 
Manned Missions & ISS Supply:
-----------------------------
Soyuz TMA-8              - Soyuz
Progress M-56            - Soyuz
Progress M-57            - Soyuz
Soyuz TMA-9              - Soyuz
Progress M-58            - Soyuz
STS-121                  - Space Shuttle Discovery
STS-115                  - Space Shuttle Atlantis
STS-116                  - Space Shuttle Discovery
 
Military Satellites:
--------------------
DMSP 5D-3                - Delta IV
NROL-21                  - Delta IV
NROL-22                  - Delta II
Navstar GPS IIR-M2       - Delta II
Navstar GPS IIR-M3       - Delta II
IGS Optical 2 (Japan)    - H-IIA
SAR-Lupe 1 (Germany)     - Kosmos
Kosmos-2424, 2425, 2426  - Proton (Glonass-M GPS)
Arirang-2 (S Korea)      - Rokot (Russian ICBM)
Kosmos-2420              - Soyuz
Kosmos-2423              - Soyuz
Meridian 11L             - Soyuz
Kosmos-2422              - Soyuz
Kosmos-2421              - Tsiklon-2

LEO Non-Military Satellites:
----------------------------
SJ-6                  - Chang Zheng 4B
Feng Yun 2D           - Chang Zheng 3A
Yaogan 1              - Chang Zheng 4B
Shi Jian 8            - Chang Zheng 2C
Cloudsat & Calipso    - Delta II
Genesis-1 (Bigelow)   - Dnepr
18 small satellites   - Dnepr                  FAILED
Falconsat-1           - Falcon 1               FAILED
Daichi                - H-IIA (Japenese Delta II)
MTSAT-2               - H-IIA
Daichi                - H-IIA
MTSAT-2               - H-IIA
Akari                 - M-V (Japanese solid fuel rocket)
SSSAT & HIT-SAT       - M-V
FORMOSAT 3            - Minotaur 1
Tacsat 2 & Genesat-1  - Minotaur 1
ST-5                  - Pegasus
Compass-2             - Shtil 1 (Russian ICBM)
Resurs-DK             - Soyuz
Metop 2               - Soyuz
COROT                 - Soyuz
EROS B                - Start 1 (Russian ICBM)

This reveals a slightly different picture. In the area of commercial geosynchronous satellites, Russia (with Proton and Zenit rockets) and Europe (with Ariane) dominate. A wide variety of Russian rockets are active in every class of space activity, while the American rockets are used only by NASA an the military.

A big portion of NASA's large budget is supporting the Space Shuttle and the International Space Station, while our competators are spending less and dominating all other aspects of space -- in particular all profitable uses of space.

American technology is still the most advanced, and NASA/JPL so far leads in recent deep-space scientific missions to Mercury, Mars, Saturn, and Pluto. American rocket technology is first rate (Delta and Altas), but the Delta rocket engine was the first major engine developed in the US since the shuttle main engines in the 1970s. The Altas uses a Russian engine -- the advanced and highly efficient RD-180.

China still remains far behind in rocket technology, missions and budget. It will be exciting if they carry out the bold Lunar missions they have announced, but thus far it is all talk and no action.

Sputnik: 50 Years

2007-07-31T19:21:00.000-07:00

Check out a small site I have prepared for the upcoming 50th anniversary of Sputnik: Link

Biography IV: Pixels and Scanlines

2007-07-24T14:52:00.001-07:00

So much for my role as part-time cable puller and system administrator. My real job at Bell Labs was to do research and publish papers. Around 1985, I changed my interest from database systems to computer graphics. I was attracted by the visual feedback of making synthetic images and the interesting underlying problems in signal processing, numerical methods, geometry, and the physics of light and materials.

Image with aliasing

Antialiased Image

I've particularly enjoyed working on ray tracing and antialiasing. Images are usually synthesized by calculating infinitesimal points, and if this is not done properly, you get a familiar pattern of "jaggies" or aliasing, as seen above left. An antialiased version is seen on the right, and that's about all I'm really going to say about a problem that occupied years of work and thought.

Turner Whitted worked at Bell Labs in the early 1980s, one of the primary inventors of the ray tracing method of image synthesis. People had worked on limited forms of this rendering technique, but Turner published a classic paper describing ray tracing with reflecting surfaces, antialiasing, and hierarchical bounding volumes, three fundamental inventions in one paper! Rob Pike got interested in my first ray tracer, and the two of us optimized the daylights out of that program. Turner's ray tracer took hours to make a picture, and ours took minutes. He was delighted, and gave a lot of help and encouragement.

Actually my first ray tracer, sort of, was at Caltech in 1979. Among other things, it did a Monte Carlo simulation of photons emitted and scattered in the Cherenkov detector. It did not result in a picture of anything, just a sensitivity map for the detector. But it did perform a lot of the basic geometrical intersection and scattering calculations that all ray tracers do.

Bell Labs Graphics (Subramanian, Amanatides, Naylor, Mitchell)

By the mid 1980s, we had a nice little graphics group in our lab. Seen above, KR Subramanian had just graduated and was working with Bruce Naylor on real-time geometry algorithms. John Amamatides and I were working on a variety of ray-tracing problems, and we had written a renderer called "FX", which was fast enough to generation animations. FX was designed to run on the AT&T Pixel Machine, a parallel graphics computer designed at the Holmdel lab around 1987.

Scene from Megacycles

John and I generated a short ray traced animation with FX and the Pixel Machine, called "Megacycles". I found it on YouTube (Megacycles). It's crude by modern standards, but a huge computation by the standards of its day.

My department head then was a talented electrical engineer named Ed Szurkowski. At the annual SIGGRAPH convention, Ed and I checked out the equipment exhibition together, and we stopped at the booth of a company that had just made a new 3D graphics board. The man in the booth was an engineer, and an old friend. He was happy to see us, and when we asked about the board, he shut off the machine and pulled the board out. Ed looked at it for about 15 seconds. As we walked away, he said, "That's interesting, I never realized you could strobe DRAM that way, they're saving one extra cycle. I'll have to try that someday!" I thought to myself, never show your circuit board to Ed.

The director of our lab was also an Electrical Engineer, named Arun Netravali. Arun was an expert on digital image processing, optimal control theory, and he had a powerful command of mathematics. We worked together on several projects, and he was the first to apply control theory to computer animation. Arun would one day become the head of Bell Labs, and I saw first hand the kind of talent and courage to act that it takes to earn that position:

Around 1988 or 1989, Zenith and AT&T formed a partnership to work on high definition television (HDTV). Zenith had an analog format and was hoping Bell Labs could design some of the microelectronics. Arun realized that the time was right for a digital standard, using modern image compression instead of television's ad hoc interlacing scheme. He gathered a few top engineers, and in almost no time, they had a complete system proposal for a non-interlaced (progressive) video signal format and the processing electronics. It would later be called "720p".

Getting vice presidential approval to proceed, Arun and Scott Knaur hired rooms full of engineers. Xilinx had recently invented the FPGA, a programmable chip designed for rapid prototyping of hardware, and this was used to build the first working implementation of the 720p video system, in almost no time. The first 720p system was a solid cube of electronics about 2 feet on a side.

The CEO of Zenith came to see it, still perhaps thinking that we might build their analog system, but he was overwhelmed by what Arun showed him. At one point during a demonstration, he said, "So Arun, are you telling me that our analog system is shit?" Arun said, "Mr. Perlman, I'm telling you the analog system is shit.". A new partnership was immediately made, where Zenith would build a radio frequency modem to modulate the Bell Labs digital signal. It's not often that big corporations turn on a dime, but in this case, there was no time to fool around.

I thought a lot about the theory of interlacing and what it meant in terms of aliasing and flickering artifacts. Amanatides and I modified the FX ray tracer to produce perfect digital video, by correctly synthesizing an interlaced signal. We presented the work at the SIGGRAPH 1990 conference. Rehearsing the talk at Bell Labs, I was somewhat more informal than in public, and I ended the talk by saying "thus proving that interlacing looks like shit". Arun slapped his knees and said, "I'll give you a hundred bucks if you say that at SIGGRAPH!". Not in front of 5000 colleagues, but my final slide said, "Interlacing sucks".

The broadcast industry fought progressive scan standards for years. The battle was till going on when I joined Microsoft years later. The computer industry supported progressive scan, because text and iconic graphics flicker terribly on an interlaced display. It is only in recent years that progressive scan has really gained support, now that the public has seen the superior quality of 480p video generated by new DVD players.

In the early 1990s, Arun met my future boss Bill Gates at a meeting of Microsoft and AT&T. AT&T had rented a private dining room at a very expensive New York restaurant. When the head waiter asked Bill Gates for his order, he said, "I don't see anything I like here. But I noticed a Burger King across the street. Could you send someone over for a hamburger and fries?" The waiter was calm and polite, but the executives from AT&T were completely unnerved.

Simulating Evolution

2007-07-17T21:19:00.000-07:00

In the 1960s, researchers in artificial intelligence took three approaches: simulation of evolution and life, simulation of networks of neurons, and algorithms to perform intelligent tasks. The MIT and Stanford AI labs specialized in the last of these, and to maximize the availability of grant money, they managed to kill off the funding of the first two approaches.
In the 1980s, the study of neural nets was reborn in work by the physicist John Hopfield, and the study quickly spread into the computer science community (the MIT AI lab had long since lost the clout to do anything about that). Genetic algorithms also came back into vogue, and in 1993 Karl Sims wrote a delightful paper in SIGGRAPH about using simulated evolution to create art.
Sims' program generated random formulas(the genome) specifying the pixel values of an image. These could be mutated and cross bred, and the user can specify which image he thinks are beautiful. The program required super computers then, but it was also written in an inefficient language (LISP). Today PCs are fast enough, and I wrote a simple image evolver in C++ which compiles directly into efficient machine code.

It's surprising how rapidly one finds an interesting image, even though the first generation of random images are usually very boring. It has been noted that cross breeding is extremely important. Evolution by just mutation and selection proceeds very slowly, but when several survivors are able to cross breed, evolution converges very rapidly on complex forms.

Here are some ancestors of that image, showing how its complex forms began to develop and evolve.
The accelerating effect of cross breeding is suggestive about evolution in the biological world. The evolution of sexual reproduction in multicellular life forms may have sparked a sudden leap forward in development, perhaps even the so-called cambrian explosion of diverse animal forms 600 million years ago.

Biography III: Institute of Higher Telephony

2007-07-12T15:20:00.000-07:00

In 1980, I quite the doctorate program at Caltech and became a staff member in Ed Stone's Lab. Rob Pike left to join Bell Telephone Laboratories. A year later Steve Johnson from Bell was visiting the campus, and he stopped by my office, asked me to lunch and then invited me to interview at Bell Labs. One nice thing about the early days of computing was the informality of the field. PhDs in Computer Science were still somewhat rare (and not necessarily desirable), so essentially my résumé was the source code of my VAX lisp interpreter.
In 1981, I started as a research assistant at Bell Telephone Laboratories. Oddly enough, many academic computer scientists eschew programming, viewing it as a form of low manual labor. This viewpoint was much more common at universities than at Bell Labs; but fortunately, there were a few prima donnas, or I wouldn't have had a job. My largest project was a distributed database system, which generated papers for a couple researchers...my name wasn't on any of them.

Bell Laboratories, Murray Hill

John Limb

Michael Merritt

My first publication came about while implementing distributed deadlock prevention in our database system. Deadlock is when one program has A and wants B, while another program has B and wants A. They will wait forever, unless one program detects the situation and gives up. I was asked to implement "wound-wait", which sometimes causes programs to give up when they don't really need to. I thought about this for a while and came up with a very different solution. I showed it to Michael Merritt, another researcher and good friend, and after some discussion at his blackboard, we found a fault. I came back the next day with an improved version, and we proved it was correct and wrote a paper.

The 1984 PODC conference was an exciting experience. I flew to Vancouver, and realized as I strolled through the airport that no one had told me where the conference was being held. Fortunately, the airport information booth knew which hotel it was in. Most of the presentations were fantastically theoretical and mathematical. My vugraphs were hand drawn with colored pens and contained not a single equation. I remembered a bad talk at Caltech, where Feynman, Zweig and Gell-Mann had badgered the speaker until he stopped and walked off the stage! But everything went fine, I just told people how we solved a problem, and I was comforted to see smiling faces in the front row.

Our paper had gotten into the PODC conference on distributed computing, but unfortunately, my boss's paper had not. She was very unhappy and told me I was disloyal for not giving the idea to her. Our department head was a no-nonsense Australian engineer named John Limb, and he just chuckled over it. A couple years later, I was promoted to full independent researcher, and John was a strong supporter.

Bell Labs had some great managers like Limb, and before you roll your eyes at that, let me tell a story: A bright but volatile scientist in our group got frustrated and quit his job. A few weeks later, he called his department head to complain about how disappointed he was in the Silicon Valley company he joined. "Well why don't you just come back", said his boss. Foreseeing this, he had tossed the letter of resignation into a desk drawer, and no one else at Bell Labs ever knew about it. A few days later, the scientist was in his office again.

Mailer Science

My first taste of corporate culture at AT&T came when John Limb brought me to a meeting about executive use of email. Email had been around for a long time, but up until then it was a computer-nerd thing. For about half an hour, men in suits puffed on pipes, and told amusing anecdotes. Then they turned to Limb, "can you set up email for us?". Limb turned to me, I said something about UUCP, and they all nodded.
Now came the real problem: "Executives don't type". Computers have keyboards, they look like typewriters, only secretaries used typewriters; therefore, executives could not use computers. The logic was inescapable, but after more discussion they had a plan: secretaries would operate the email and give printouts on paper to the executives.

Someone gave us an email address to test, and the next day I sent him a message. No reply. I tried the next day, but still no reply. The next day, Limb came into my office and told me he got a call complaining that some presumptuous technical assistant had been sending email to an important director. Limb chuckled once again, "I guess their email works!"

Electronic mail looks deceptively simple, and hackers who work on the problem consistently underestimate and botch the job. Mailer Science was the jargon at Bell Labs for that special brand of bad programming that goes into email software. Peter Honeyman did some good work on UUCP, and tightened up its security. But the SENDMAIL program from UC Berkeley was the source of countless problems. Today, spam and viruses are possible, in part, because of bad security in Berkeley's SMTP protocol, still used by UNIX systems.

When Robert Morris Jr. brought down most of the internet, with a fast reproducing worm, it was a misfeature in SENDMAIL that he primarily exploited. And unbeknownst to me, he also exploited a program I wrote. I had recently completed a high speed implementation of the DES encryption algorithm, and I knew a slightly modified form of DES was used by UNIX to verify passwords. Robert and I altered my code and created a program that could check passwords 20 times faster than the system routine. He used this in the worm to guess passwords, by rapidly trying about 30,000 words.

In the early 1980s, there were numerous computer networks, usually centered around particular brands of computers. BITNET was operated by IBM, the ARPANET was mostly made up of DEC PDP computers running the commercial TOPS operating system, MECC and PLATO were examples of huge networks run by Control Data. The UUCP program in UNIX allowed computers to network (sort of) over ordinary phone lines, mainly to exchange email. A system of "netnews" forums was also using the same transport system as email. I remember reading all of netnews every day, but few years later netnews (USENET) traffic was thousands of times larger. This email network was strongly supported by UC Berkeley, Bell Labs and DEC, and our lab's machine "allegra" was a key hub.

An Ever Widening Tangle of Cables

Several technologies played a critical role in creating the internet. One was support for the TCP/IP internet communication protocol on UNIX, the most popular OS by then. This was done first at the Wollongong company, and a couple years later in Berkeley UNIX. Another was Metcalfe's invention of Ethernet, which made it easy and cheap to plug minicomputers together. Finally, CISCO built IP routers, which allowed companies and universities to gang together their ethernets, into organization-wide networks.

Leonard Bosack: CISCO routers

Bob Metcalfe: Ethernet

Vint Cerf: TCP/IP

From what I witnessed, the internet grew organically, bottom up, by this process of hooking machines together, with ethernet and commercial routers. National and international connections were made by leasing T1 or T3 lines from the phone company, and as demand for long-distance bandwidth grew, the modern system of backbones and hubs evolved. Email connectivity had preceeded internet connectivity, playing an important role in establishing a UNIX user community.

Our lab was an early adopter of UNIX internet techniques, using Berkeley UNIX (before "sockets"), Wollongong TCP/IP, and ethernet. John Detraville, Bill Schell and I were the primary hackers who put that together, installing servers and pulling yellow ethernet cable down the hallways (well, until the Union told us we had to let them do it). When things stopped working, we learned to use a reflectometer to locate bad connections somewhere above the ceiling tiles or under the floors. John had a very accurate vision of where computers were heading. Thanks to him, we were very early to replace VAXs and terminals with SUN workstations, buying from Cadlinc at first and then SUN Microsystem. This was a general trend everywhere, a second revolution in the hardware industry, with microprocessor-based workstations supplanting the minicomputer.

We took some flak within Bell Labs for operating an internet. AT&T's engineers were brilliant, but they viewed the internet as amateurish and inconsequential. Frankly, AT&T's networking technology was way more sophisticated, based on lossless packet transmission through token rings and photonic switches. But Bell Labs dropped the ball when it came to providing a glue to interconnect computers practically. TCP/IP might not have been the ideal solution, but it worked. The big competator was OSI, designed by standards committees and professors, it became so elaborate and overdesigned that no one ever got it to work efficiently. OSI was a multi-billion-dollar misstep for Europe, and only Finland was wise enough to build a national network based on TCP/IP.

We also took flak for running Berkeley UNIX in our lab (1138). By now, AT&T was selling a version of UNIX called System V, and they were unhappy that nobody in Bell Laboratories would run it. The folks who invented UNIX, in our sister lab (1127) were unhappy that we were not running their UNIX Version 8. But we wanted to track what the "real world" was doing. From this time on, the evolution of UNIX was largely dominated by SUN Microsystems, where most of the key developers of Berkeley UNIX went.

Histories of the internet tend to privilage the role of academics and "hackers", while not giving much credit to the engineers and corporations who solved important hard technical problems. As the internet grew in scale, CISCO and other companies had to invent replacements for the simple ARPANET routing algorithms. The original TCP/IP is just one of hundreds of transfer protocols today, like PPP, Microsoft Point-to-Point Compression (MPPC), and others, needed to pass data efficiently over phone lines, television cables and high-speed trunks. It's romantic to think that young "hackers" really did everything, and for various reasons industry pundits have written books about that. Probably no one will ever write a book about all the hard work and all the millions of large and small inventions that professionals have made.

In the mid 1980s, UNIX and the C programming language spread rapidly, consuming the academic and hacker cultures centered around DEC and IBM operating systems and the LISP language. The MIT AI Lab was particularly marginalized by the success of UNIX, and frustrations there smoldered for years to come. An anti-unix movement called GNU began, but all it produced were duplicates of the UNIX commands (bison for yacc, gcc for pcc, groff for troff). An operating system kernel was promised but never completed. GNU's founder Richard Stallman visited the hated Bell Labs, and many of us were disturbed by his behavior and personality. I thought he was a megalomaniac. When Rob Pike made a reciprocal visit to MIT, his talk was disrupted by heckling from Stallman and his followers.

Biography II: Cosmic Rays and UNIX

2007-07-10T12:52:00.000-07:00

In 1978, I started graduate school at the California Institute of Technology. I was still officially a physics student, viewing computers as more of a hobby. Caltech was a great place to study science, with Nobel prize winners like Richard Feynman, Max Delbrück and Willie Fowler.

Ed Stone

Downs Laboratory

Although I would ultimately not persue physics, I could not have encountered a better professional role model than my advisor, Ed Stone. Ed had a rare combination of talents and character traits. I never saw him lose his cool or treat anyone inconsiderately. He was a hard working, skilled scientist, who did careful high-quality work. His proposals for funding had better scientific analysis in them than most other people's journal papers.

Ed was also a talented administrator, chosen to lead NASA's Voyager mission. I was lucky to be there for the busy Jupiter and Saturn encounters. Behind the scenes, careful planning packed in as much scientific investigation as possible as the spacecraft whipped past each planet. A complex schedule of events was developed to change spacecraft orientation, activate different experiments, and take pictures. Ed was the calm eye of the storm, surrounded by PERT charts, ringing telephones, and stressed out investigators all talking at once. It was no surprise to me when he later became the head of JPL.

HEAO-C Spacecraft

I worked on HEAO-C, a minivan-sized satellite designed to measure the rare heavy-nuclei component of cosmic rays. We spent some time where HEAO was built, at Ball Corporation, a company that makes canning jars and spacecraft (I kid you not). A staff programmer and I wrote the software to analyze HEAO-C3 data. I also wrote a Monte Carlo cosmic-ray tracer that simulated the bombardment of the instrument and helped calibrate the device and test our software. Once real telemetry data began to arrive, we used silicon and iron nuclei to complete calibration. The interesting heavy nuclei were run through a series of programs like "Cobalt Mine" and "Gold Mine" that sifted the cosmic rays into rarer and rarer catagories.

Another computer enthusiast in Ed's lab was Rob Pike, who also joined Ed's lab in 1978. He convinced us to run UNIX Version 6 on our PDP-11 computers, an operating system invented at Bell Telephone Laboratories. The University of Toronto and the University of New South Wales were important early adopters of UNIX, and Rob had come armed with the UT distribution tape and a famous commentary on the system by John Lions from UNSW.

UNIX had an elegant design that allowed users to combine simple operations into powerful computations. Simplicity is the hardest thing to do, and especially rare in software, which tends to be overdeveloped. I admired the disciplined restrained Bell Labs programming style, reminiscent of Mansfield's work at Control Data. I got to know the V6 UNIX kernel like the back of my hand, and I wrote device drivers for our magnetic tapes and plotter.

The C programming language, also invented at Bell Labs, was used to implement UNIX. Many programming languages are proposed, but very few appeal to professionals in the real world. C became popular because it contained current ideas about program flow control and data-structures, but it also allowed precise control of the low-level operation of a machine (manipulating memory addresses, shifting bits, etc).

Our PDP-11/70 Computer

In the late 1970s, the minicomputers built by Digital Equipement Corporation (DEC) were creating a revolution in the industry. Based on inexpensive CMOS integrated circuits, they were not as powerful as mainframes, but they were a hundred times cheaper. People bought them like hotcakes, and soon, DEC replaced IBM as the biggest seller of computers in the world. It was the first of several such revolutions I have seen in just a few decades.
The Caltech Astronomy Department was one of the first to buy a VAX, DEC's 32-bit successor to the PDP-11. But one night, an explosion smashed its circuit boards and blew off the doors; the result of an oatmeal-box-sized eletrolytic capaciter installed with the wrong polarity. In Lauritsen Laboratory, the High-Energy Physics Department also bought a VAX, and Rob Pike and I helped install UNIX 32V. It did not explode.

In retrospect, I hope we did the right thing for the users of that machine. The VMS system that came with the VAX was technologically superior: more efficient compilers, virtual memory support and a high performance file system. Even years later, Berkeley UNIX could not match the performance of VMS. But UNIX had many progressive features, and it was something we could tinker with. In the university environment, UNIX was soon dominant.

A little known fact about the history of UNIX is that virtual memory support for VAX UNIX was first done at Bell Labs by John Reiser. He modified the disk buffering subsystem, unifying disk caching and virtual memory into one mechanism. The results were impressive, and Reiser's change was so subtle that it was hard find, reading the source code. I believe it was more efficient and elegant than the VM system done later at UC Berkeley.

Rob and I also worked with Stephen Wolfram on his early symbolic math systems. I wrote a second LISP interpreter for the VAX as part of that project. Our original plan was to compile the MACSYMA program, or perhaps translate it from LISP to the more efficient language C. When the six-inch-thick source printout arrived, we were dismayed by its size and tangled "speghetti code" design. Stephen eventually wrote a new system called SMP in C, using more efficient specialized data structures to represent algebraic expressions.

Biography I: Minnesota Hackers

2007-07-06T19:07:00.000-07:00

In 1972, computers filled large rooms, consumed enormous power and costs millions of dollars. As a 16 year old boy in a rural Minnesota, I was lucky when our high school got access to a Control Data Corporation timesharing system. Our algebra teacher Gerald Polly set it up, and for a few months our programs had to be mailed to a nearby college to be typed in and run. But soon we had our own teletype with a 110 baud modem.
Computers were not an everyday part of life then, and my image of the distant mainframe was colored by science fiction movies like Colossus: The Forbin Project. The first time I typed to the computer I was somewhat intimidated, but soon I was fascinated. The class was taught BASIC, a toy languaged used to teach programming. After a few weeks, I borrowed a FORTRAN manual form the Rural Electric Cooperative and switched to that, a real-world language invented at IBM for scientific programming.
Computers are remarkably fun. People enjoy building things and seeing them work, they enjoy solving puzzles, they enjoy improving and polishing a creation. Programming is quite satisfying in all these ways, and because computers are such general-purpose machines, we still have no idea what the creative limitations are.
In 1974, I attended the University of Minnesota, where they had several Control Data computers, including a powerful CDC Cyber 74 mainframe. This was one of the most brilliantly designed computers of all time. Seymour Cray's ideas of multiple functional units and pipelining are essential elements in modern processors like the Intel Pentium.

In nearby Madison Wisconsin, members of a protest movement had recently blown up a science building, killing a student. Computers were also a favorite target for activists, and so the University had moved its machines to a remote and little-known location. I didn't get to visit and photograph the site (see above) until after I graduated. But Control Data was very good at networking and communications, and we accessed the machines through card-reader stations or interactive teletype terminals.
In the 1960s and 1970s, this was a good place to be. Minneapolis was a major center of computer technology then, the home base for Control Data Corporation, Univac, Honeywell, Burroughs, and important branches of many other companies like IBM.

Timesharing operating systems take turns working for a moment on each user's task, amortizing the expensive computer over many customers. This idea was worked on widely in the early 1960s, at System Developement Corporation (SDC), MIT, University of Michigan, Dartmouth College, and others. With its focus on ease of use, Dartmouth's BASIC timesharing system was probably the most important and influential on industrial practice, adopted by General Electric, HP, Univac, CDC, and probably others.
At CDC, Dartmouth's concepts were extended into a powerful multi-language system called MACE, and later KRONOS. Those operating systems were beautifully designed and programmed, with much work by one professional programmer at Control Data named Greg R. Mansfield. Using parallel tasks running on the central processor and 20 peripheral processors, KRONOS could serve hundreds of concurrent users on a machine that only ran at 10 MHz. This kind of efficient programming was extraordinary (in contrast, the MULTICS system developed at MIT was so inefficient that only a couple users could work at once).
Like most colleges, we had a "hackers" club, the Meritss User Group (MUG). Jeff Drummond and I were the two members at the Morris campus. The University gave us privilaged accounts and minimal supervision. Programmers would work in the computer center until it closed, then move to a nearby commissary and unroll listings and talk until the small hours of the morning. My big projects were a LISP interpreter, written in 6600 assembly language, and COINNET, the encrypted bulletin board system used by MUG. The way the club's mentoring system worked, I had a MUG account, a younger student named Harley Grantham shared it, learned the ropes, and then took over when I graduated.


43052                  UNBIND   MX0    -18
     5010000000                 SA1    A0+0
               20036            LX0    30
6130000001                      SB3    1
          6221000000            SB2    X1+0
56120                  UNBIND1  SA1    B2
     54203                      SA2    A0+B3
          63210                 SB2    X1
               20136            LX1    30

The CDC 6600 had a 60-bit word, a number chosen by Cray and the Babylonians, because it is divisible many different ways. Machine instructions are 15 or 30 bits long, so good code was written to make sure each word was completely filled, as seen above. There were parallel functional units for shifting, loading memory, addition, multiplication, boolean operations, conditional branches, etc. So it was a challenge to keep all the units busy, doing an instruction every clock, without stalling on register conflicts or busy units.
Hacker cultures are really youth gangs -- kids trying to initiate each other into a craft, but often without the guidance of older professionals. Actually we did have a mentor whom we never met in person, G.R. Mansfield, the author of CDC's operating system. Mansfield did clever, sometimes startling things to maintain a flow of nonconflicting simultaneous computation in the functional units. On a larger scale, the overall design of his systems was elegant and efficient. His programs were also neatly written and commented, a serious effort made to be readable by other programmers. This was a great example to follow, and most MUG members wrote code that was cleaner and more professional than typical hacker style.
It is interesting that Control Data included the source code of their system, as part of their online documentation. Computer hardware was so fantastically expensive then, the operating system software and compilers were viewed as free accessories. Futhermore, the software was highly machine dependant, and so Control Data didn't worry about IBM or Univac stealing their software. When hardware costs dropped to the levels of software development costs, the economy of the industry turned upside down, but nobody foresaw that in the 1970s.

On Being Contrary

2007-06-30T16:37:00.000-07:00

A young friend was telling me the other night about a political science professor at UW who walked his class through several political dogmas. Each was presented as impressive, compelling and correct. And at the end, he explained that exposing people to a series of convincing arguments like this was a good way to prevent people from simply accepting the first dogma they encounter and becoming a fanatic. I was very impressed by the wisdom of that teacher.

As a young person at the University of Minnesota in the late 1970s, I took some classes from a young communist history professor who indoctrinated us in Maoist philosophy and guerilla war tactics. She was a far cry from that UW professor. By the early 1980s, I was working a little with TechNica -- a project to help support the Sandinista revolution in Nicaragua -- and some of my friends at Bell Labs secretly travelled there via Mexico, helping to build computer infrastructure and establish university courses. I'm not saying that was bad, but we definitely had a very strong political viewpoint and bias.

Luckily for me, there is something contrary in my nature, a nagging skepticism when a beloved theory starts to show holes, a healthy amount of cynicism about power and altruism. With the fall of the Iron Curtain, a landscape of toxic industrial pollution and stifled human spirit was revealed. Around the same time, an orgy of free market capitalism was creating microelectronics, the personal computer and internet culture; bursting beyond the decades of relatively dull academic tinkering with the ARPANET. In 1994, I dropped out of graduate school (for the second time) and went to Microsoft, because I really felt that was were the action was.

I used to think that Marx had it right, that economics and injustice were the forces behind history. Eric Hoffer (author of The True Believer) opened my eyes to the fact that what was really driving human history is monkey politics -- one asshole after another who wanted power -- and Marx was just one of those assholes. The formula for success -- create a compelling and impressive dogma that vilifies the status quo and extols some semi-logical explanation for why you will be a superior person if join his movement. People fall for this in droves, both the stupid and the intelligent, in droves. Racial purity, political correctness, born again in Jesus, running Linux on your PC -- from grand ideas to petty -- people love a story that tells them they are better than those who are more successful or more talented. One should not strive for the Self, unless of course you are one of the movement's leaders, in which case you will likely be rich and have groupies in your bed every night.

It's hard to corner anyone long enough to do what that fine teacher at UW did, and walk them through a long series of political or religious ideologies. To teach them to search for Truth, but not get stuck in a locally optimum system of beliefs. And I suspect it works best on young open minds like my friend. Personally, I cannot resist the temptation to be contrary, to point people at some embarrassing flaw in a popular dogma, or some annoying piece of evidence in favor of an unpopular theory. You have to explore and question and encounter surprises. I'd even go so far as to say that to get out of a locally optimum belief, you may occasionally believe something that is completely wrong, and a week later you will be red faced with embarrassment as you correct yourself. True Believers never experience those little mistakes, because they are trapped in a life of devotion to some great stupid idea.

The R-7 Rocket

2007-05-14T17:10:00.000-07:00

50 years ago, the Soviet Union test launched the R-7, the world's first ICBM. It's design of parallel expendable boosters was devised by the mathematician D.E. Okhotsimsky, who considered a variety of schemes for maximizing the range of a rocket by ejecting portions of its construction during flight.

Seen above left is one of the first test launches of the ICBM. To the right is a modern Soyuz rocket, with its additional sequential stages. The R-7 was capable of placing the 1.3 ton Sputnik-3 satellite into orbit. The modern Soyuz with its additional stages can place 7.4 tons into low Earth orbit.

With 50 years of use and about 1700 missions, the R-7 family is arguably one of the most important rockets in the history of space exploration.

Biology of Sexual "Morality"

2007-03-11T16:43:00.000-07:00

A time-honored method of creating moral outrage against a public figure is the sex scandal. But is this about morality or is it just about the biology of our selfish genes?

It's a complex thing to be a social species. As a whole, we benefit from cooperation and altruism, but as individuals we can benefit from selfish behavior and take advantage of the social system. Like all social animals, we have evolved to detect cheaters and cowards who benefit from society without returning anything to it. Like other social animals, we are political, we form pecking orders and alliances. According to evolutionary psychology (http://www.psych.ucsb.edu/research/cep/primer.html), human intelligence has actually evolved to its high level, primarily to solve complex problems of politics and competition with each other.

One outcome of the evolution of behavior and mind is sexual politics, the development of behaviors that improve our chances of passing on our genes in a social context. One behavior that is almost universal in social animals is the impulse to prevent other individuals from breeding. This is not a conscious desire on our part, but we have certain impulses that encourage our genes to propagate more than others'. In particular, when we see or imagine other's having sex, it is upsetting.

In Frans de Waal's classic book, Chimpanzee Politics (http://www.press.jhu.edu/books/title_pages/1293.html), he describes this behavior a closely related species. In the image above, we see a dominant adult male punishing a younger male whom he caught attempting to mate with a female. The sight of other chimps having sex causes immediate rage in an adult chimpanzee, and this behavior leads to strong male chimps mating more often than their competitors.

As civilized human beings, we tend to interpret these type of feeling as "moral outrage", although their origin is much more primitive and genetically selfish. To avoid the negative consequences of sexual politics, we've learned to keep sex private. We've agreed to monogamous marriage as a fair and equitable scheme to prevent what is seen in some primitive societies and religious cults: a sexual monopoly by a few strong males with multiple wives.

But we've also learned to make political opportunity from these instinctive responses. By publishing sexual gossip about a public figure -- such as an affair or an unusual sexual orientation-- mental images of the other person engaging in sexual activity are invoked; and thus, an instinctive feeling of anger or anxiety is stimulated.

Stoopid Robot

2007-02-16T20:21:00.000-08:00

I manage a small private forum, and I've noticed that sometimes it slows to a stop. In fact, something is hammering on my server and running so much ASP script that my whole website becomes slow. Then I figured out why:

Yahoo Search Robot! It was logged into my forum 11 times. I turned off guest read access, and everything instantly became normal and speedy again. But the Yahoo search server was going nuts. 20 guests (as seen above). Then 30 guests! All getting access denied.

I also turned on robot exclusion on my site (robots.txt and the META tags), but this is not stopping the Yahoo Search Robot from trying to crawl my forum in the most obnoxious possible manner.

Don't Pitch All The Paper!

2006-11-23T18:24:00.000-08:00

Many libraries have found they can save space and make information more available by scanning their vast holdings of journals and conference proceedings, converting the result into PDF formated files. That's good news for people doing research on-line. But here is a problem:

This particular journal article contained a photograph, but when journals are quickly scanned and compressed, the result is the almost complete destruction of the image data. This is actually a pretty good example. It's not unusual for photos in a paper to be reduced to a black rectangle with some white blobs.

Here are a couple more examples. This is bad news, since as Adobe's advertising campaign says, libraries can "Pitch the Paper!". Let us hope that we do not find one day that some important historical images are completely lost in this process.

Of course, PDF is capable of storing images at higher resolution. But it takes time and care to scan a paper well enough to preserve a good record of a photograph. In practice, it just doesn't happen -- thousands of journals have to be processed, using default settings that compress the data well but ruin the images.

Personally, I wish scientists would use rich text format instead of PDF. I'd like to be able to read a science paper, click on a graph and see a spreadsheet of the original data pop up, as it does with MS Word. But the ability to embed original data and images in a paper is rarely used.

Batteries, Bombs and Rocket Fuel

2006-09-28T20:45:00.000-07:00

Two recent questions strangely converge, what is a good rocket fuel and what is a good battery for a laptop PC. It got me interested in how much energy can be stored in a given mass.

At Bell Labs, I remember a great talk given in 1985 by the head of the Physics department. He talked about the exponential growth in network bandwidth, memory density and computing speed. But he noted, battery lifetime is limited by chemistry and is only asyptotically approaching a modest limit. The latest seems to be the Lithium Ion Polymer battery, which is finding use in mobile devices. The recent stories of exploding laptop PCs are a clue to just how much the energy density of batteries is increasing.

Let's look at the specific energy density (kiloJoules per kilogram) of some technologies:


Ultracapacitor ............... 50 kJ/kg
Lead Acid Battery ........... 100 kJ/kg
Ni-Cd Battery ............... 200 kJ/kg
Alkaline-Manganese .......... 300 kJ/kg
Lithium ion Polymer ......... 600 kJ/kg
TNT ....................... 4,000 kJ/kg
LOX/LH2 .................. 13,000 kJ/kg
Nuclear Fission .. 90,000,000,000 kJ/kg

We can see that chemical batteries still have a long ways to go before approaching the energy density of chemical fuels and explosives. Liquid oxygen and liquid hydrogen (LOX/LH2) is the about as good as it gets from chemical energy density, which is why they were chosen as the ideal rocket fuel by K.E. Tsiolkovsky over a century ago. And wouldn't it to use a laptop for one week instead of just six hours, per charge?

Ultra capacitors are interesting. Although they are just now catching up to batteries, in theory they might someday rival the density of any chemical energy source. One advantage they already have over batteries is almost infinite lifetime. The D-cell compatable capaciters seen above are rated for 500,000 duty cycles.

Two Perverse Questions about Venus

2006-09-13T18:00:00.000-07:00

When I show people pictures of Venus, I get two very common and somewhat perverse questions. OK, I'll give them a shot:

What is left of the Venera landers today?

Venera-9 style landers were built mostly from titanium and ceramic. So structurally, they are probably still sitting there. Of course, internal electronics (plastic insulations, circuit boards, etc) would be burned up. It is possible that liquid in the large chemical batteries might have boiled and ruptured the main spherical pressure hull, but only if the internal pressure could exceed 100 atmospheres. I'm not sure it could do.

What would happen if I stepped out onto Venus?

Very bad idea. The surface temperature (870 F) is about that of an oven on self-cleaning mode. The high density (1/10th of water) would greatly increase thermal transfer, like a liquid would; however, the atmosphere is still a gas. Supercritical carbon dioxide would not support rapid oxidation (flaming combustion), but it does act as a strong non-polar solvent, sometimes used for dry-cleaning. So I believe it would have the effect of being french-fried in mid air, and quickly reduced to a charcoal figure. A lurid motion-picture special effect waiting to happen. :-)

Martian Futures

2006-07-16T16:48:00.000-07:00

Space exploration is a magnet for crank science. It's nearly impossible to talk about something like intersteller propulsion and keep people on the same page as real-world physics and engineering. And it's even more difficult to talk about far-reaching ideas like colonizing planets without drifting into the realm of science fiction. But here I go anyway.

Consider the famous scenes in 2001, where a NASA official flies to a beautiful space station operated by Pan Am airlines and then on to a Lunar colony. You're looking at a simulated trillion dollar infrastructure, but why was it built? Who is using it? Who is paying for it? How does it make money? What are people doing on the Moon that is worth all this? These are issues that science fiction simply overlooks.

As in 2001, the analogy is often drawn between the airline industry and a future spaceflight industry. The difference is, on the Earth there are real destinations to fly to. There are countless social and economic reasons to travel from one populated region to another on the Earth. This is not the same as spending billions of dollars to fly to Mars, pick up a rock and return to Earth. For spaceflight to be practical and large-scale, there must be a reason, there must be a destination.

People talk about things like mining helium-3 on the Moon. Both technically and economically that's nonsense. At present, there is nothing remotely valuable enough to pay for the cost of mining and interplanetary transport. But more importantly, these ideas represents a fundamental misconception about wealth, in the sense defined by Adam Smith. Real estate is valuable because people want to live there and work there. Human activity is the true definition of wealth, and human presence is what makes a destination interesting.

Thus, colonizing space is a bootstrapping problem. it is a problem in economics, not engineering. If Mars had an atmosphere and a population, it would be of incalculable value, and people would pay to travel there and back. But how do reach that point? The technology of cheaper travel and terriforming Mars is fascinating to speculate about. I believe it could be done almost entirely with robotic technology. But that is not what blocks us from proceeding. The real problem is developing a mechanism for funding, when there is a huge return on investment but a turnaround time of centuries. You would have to create a Martian Futures Market that people have genuine confidence in -- a serious enterprise that makes steady progress, backed by corporations with proven expertise and probably at least one first-world government.

Maybe you have to engage people's territorial and competative instincts. Let's say America declared that it was going to unilaterally colonize Mars and annex it? After the obligatory student protest marches all over the world, I believe other nations might start a competing program! And then it's hard for anyone to back down. If both programs make enough progress, investors will want them to merge and cooperate eventually. It is just too expensive to duplicate the effort.

Some Cool And Completely Random Words

2006-06-26T17:46:00.000-07:00

Apocolocyntosis - To turn into a pumpkin. Dating back to Roman times, it was considered a humorous play on the word "apotheosis" (to be deified).

Bezoar - A human hairball, believed to be a universal antidote to poison.

Cenogenesis - The temporary formation of gills and other atavistic features in the human fetus, leading to the adage "Microgeny recapitulates phylogeny", development of the creature plays out the evolution of its species.

Fusel Oil - Contaminants in alchoholic beverages responsible for hangovers, consisting of higher aldehydes and ketones.

Hagiography - The biography of a saint. 19th century occultist Aleister Crowley wrote a book he described as an autohagiography.

Lysenkoism - Unsupported scientific theory promoted for ideological reasons, named after the Soviet biologist empowered by Stalin who attempted to suppress the theory of evolution in the USSR.

Oubliette - A dungeon cell with a trap door in the ceiling.

Revenant - A person who has returned from the dead.

Trilithon - A pair of tall stones supporting a horizontal lintel, such as at Stonehenge.

Wergild - Money paid to a family as compensation and penalty for murdering one of them.

Zoarium - A super organism formed from the combination of individual creatures.

Heavy Metals

2006-05-13T18:18:00.000-07:00

Metal dyes are based on transition metals, whose inner electrons happen to resonate at frequencies in the visible-spectrum of light. From left to right are seen:

Nickel Amonium Sulphate

Copper Sulphate ("Blue Vitriol")

Potassium Permanganate

Cobalt Glass

Venus-Mission Trajectories

2006-04-26T16:15:00.000-07:00

I wrote a program in C++ to calculate interplanetary trajectories. It looks up the planetary positions in the JPL ephemeris database, and calculates the Keplerian orbital elements of a probe trajectory by Lambert's theorem. So, given the departure time and arrival time, I can find the unique orbit that fits those two points at those two times. Here is the trajectory of the Soviet probe Venera-1.

I also compared distance values with Soviet ranging data. The first three ranges were measured by the CWFM radar data, measured from the Pluton system in the Crimea. The rest were calculated by their ballistics center.

Russian Value My Calculation
Feb 12, 03:45 GMT 26000 km 23269 km (1st telemetry session)
Feb 12, 11:25 GMT 165000 km 142001 km (2nd session)
Feb 17, 11:35 GMT 1889104 km 1889500 km (3rd session)

Mar 4 00:00 GMT 6.9 million 6953121 km
Mar 25 00:00 GMT 15 million 15243053 km
Apr 13 00:00 GMT 28 million 27796154 km

I believe my early numbers would be better if I was accounting for the Earth's gravity. The probe would be launched faster than I calculate, but then slow down from the pull of gravity until it assymptotically approached the Lambert orbit.

Free, As In Free Beer

2006-04-20T12:12:00.000-07:00

When I switched from UNIX to Windows ten years ago, I became a big fan of Visual C++. I was happy to see today that Microsoft is making an Express version of the tool available for free, forever (it was originally intended to be free for a one-year trial period).

http://msdn.microsoft.com/vstudio/express/

They also are giving away a free version of SQL Server, which is good news for small websites. I've used the full version of SQL Server, and it is also remarkably easy to set up. And along with DB2 and Oracle, it is a serious product, not a slow buggy ersatz database system (you know who I'm talking about).

I was pleased to see that Daffodil has finally run the TPC-C benchmark on some of the free database systems ona 1.7 GHz PC. This is something the makers of these products have resisted for years, although until recently they have not really had the feature capabilities:

PostgreSQL - 62 transactions per minute
MySQL 5.0 - 483 tpm

On the TPC website, let's see what the big boys do. On PC workstations:

MS SQL Server, 2.8 GHz Dell - 38,622 tpm
DB2 on HP Proliant - 18,661 tpm

And of course the professional systems are tuned for multiprocessor systems, where they go absolutely nuts:

IBM DB2 - 3,210,540 tpm
Oracle 10g - 1,601,784 tpm
MS SQL Server - 1,231,433 tpm

Palette of the Planets

2006-02-08T20:01:00.000-08:00

Over the years, I've been accumulating a small database of color spectrums, as part of my C++ graphics library. I've been tinkering with a solar-system renderer/simulator lately, and I decided to work on calibrating planetary images. NASA is notoriously bad about punching up the color of planets to make them look more "interesting".

So what is the average color of the planets? Easily answered with a little digging, because the spectral reflectivity (albedo) has been measured carefully for all of them. Take that, multiply it by the spectrum of the Sun, convert to CIE XYZ, and then convert to 24-bit sRGB, a gamma-corrected color format that computer monitors and HDTV's are calibrated to display. I scaled XYZ to make Y equal to the total geometric albedo of the planet (but I am not including the effect of distance from the Sun).

I have never seen a correct image of Venus, which is usually an ultraviolet imaged colorized orange or blue or even purple. It fact, to the naked eye, Venus is cream colored and featureless. The Earth is somewhat violet because of the blending of blue with the reddish colored land. And Mars is more brownish-orange than red. Overall, the real palette of the planets is more subtle than usually portrayed.

I added a second set of colors for major moons and the three major asteroid types. Note how dark carbonaceous objects like Phobos and Hygiea are -- a very primitive form of matter.

The Molniya Rocket

2005-12-17T23:08:00.000-08:00

I needed a good photo of the Soviet interplanetary rocket, the 4-stage Molniya. I decided to redo an old panoramic composite that really shows its engines in action, starting with a video of the Venera-7 launch. The camera was fixed to a gantry and filmed the rocket as it rose past it, so the composite is an almost orthographic view.
I stripped the color out in LAB color space (doing it in RGB seems to leave block-coding artifacts behind). Then I did the composite in Panorama Factory. Normally I prefer the superior MS Digital Image Studio panorama stitcher, but for some reason it couldn't get a lock on matching the frames, probably because of the stationary tower on the left side of the frames.
I adjusted the proportions of the rocket to be accurate, comparing it to known still photos. The background was repeated of course, and not useable, so I averaged it out the and replaced it with a similar photo of a sky.

The Wheel

2005-09-29T01:32:00.000-07:00

The invention of the wheel is commonly considered trivial, the source of jokes about cavemen carving stone tires. However, it was not the round tire that was the trick, it was the axle bearing.

It is virtually impossible to make a bearing from wood alone. Even with liberal use of grease, turning wood against wood at high speed is a good way to invent fire, not the wheel!

To build carts, such as the Sumerians, Egyptians and Romans used, the bearings must employ metal. The first image shows the remains of iron journal bearings from a Roman racing chariot -- a challenging problem requiring light-weight tires and durable low-friction bearings. By Roman times, carriages had spoked wheels, iron bearings and shock-absorbing suspensions. This technology remained in use up until the days of the Conestoga wagons of the American West.

Modern bearing technology is remarkably sophisticated, including hard ferro-alloys, synthetic lubricants and precision machining impossible even a few decades ago. The most sophisticated bearings do not even allow the axle and sleeve to touch at all -- such as the gas-wave bearing or the magnetic bearing. These are essential in devices like gyroscopic inertial guidance systems, where gyro wheels may turn at 60,000 rpm.

Beep Beep Beep...

2005-09-16T09:20:00.000-07:00

What did the world's first satellite, Sputnik-1, sound like? I'm skeptical about the authenticity of many alleged audio recordings of Sputnik. This one on NASA's website has been copied thousands of times, but I do not believe it is actually Sputnik-1:

http://www.hq.nasa.gov/office/pao/History/sputnik/sputnik.wav

In fact, pretty much all the facts about this satellite's signal are incorrect, so I poked around and found some reports by Sergey Korolev. Sputnik-1 transmitted a 1500 Hz tone, alternating between a carrier frequency of 20.005 and 40.002 MHz every 0.4 seconds. The tone did not carry pulse-duration-modulated telemetry, it was just a fixed rate of beeping. However, if the nitrogen pressure inside the spherical hull dropped below a critical level, a relay would change the pulse rate, indicating a probably micrometeorite puncture, which did not occur during the three weeks of transmission.

I was able to find a gramaphone recording made by a ham radio enthusiast in 1957. The sound quality was terrible, but a little filtering brought out the pulse tones very nicely. So here is Sputnik-1:

http://www.mentallandscape.com/V_Sputnik.mp3

Typography

2005-09-11T06:52:00.000-07:00

Since I am writing a book, I thought I would discuss some design choices. This book, _The Soviet Exploration of Venus_ is being set on 8.5" x 11", the largest page size that lulu.com supports. I may or may not send it to them, but their color book production is excellent (I ordered some photo books just to check). This is a somewhat odd size for a book, almost big enough to do two-column, but not really.

I read some articles, and most importantly looked at some books I liked, to plan layout. It's important to relieve the eye by not packing the whole page with dense text, especially with only one column format. I made a good wide 2" outside margin and 1.5" lower margin. The book has a ton of photographs, and big margins lets you push them out to 0.5" from the edge of page, so that space gets used in interesting and varied ways. I calculated a set of standard photo width for inside and outside margins, designed to always leave a full, 2/3, 1/2 or 0 column of text beside them. Keep things simple, only present the reader with a few familiar proportions! I put photo captions in the lower margin, not under the photos. I only saw one example of a book that did that, but I liked it a lot. Finally, photo heights are trimmed to be multiples of 14 points, the line spacing. A lot of books don't bother, but this keeps an exact 1/4" boarder around all sides of every photograph, which really looks neat.

I don't know enough about fonts to be a snob about it, but I did avoid the way-overused Times Roman and Ariel. You want a nice old-fashion readable serifed font for the text. Don't give in to temptation to use some modernist font, unless you are writing a book about migraine headaches or eye strain! For captions and section titles, I chose Trebuchet MS, which is a fantastic "humanist" sans-serif font. Humanist means the letters are more ornate and old fashion, not just geometrical.

B/W photos have a 5% burgandy tint, almost unnoticeable. I didn't want to use sepia, giving an impression that Soviet technology was old-fashion. Tinting makes for a smoother print, because it engages all four of the CMYK ink dots. If I could submit full CMYK image files, I might have tried to do black-gray duotone, but that's a hassle, so I just tinted them.

I'm doing the layout in Microsoft Word 2003. I know that software, and with a few font styles and two macros, the workflow is fast and easy. Don't even THINK about using an earlier version of Word though, and don't start a big project like this unless its also on Windows XP. Remember the bad old days of Word crashing, like ersatz Open Office still does! But really, that doesn't happen anymore, its a pretty solid program. A more important concern is the typography engine, do the paragraphs look nice. Here, Office 2003 seems to also have made a big improvement. Ultimately, if I don't like it, I will buy Adobe InDesign or QuarkXPress and just redo it. Once the text is written, photos are sized and the layout is defined, it would really only take days to do it over again in another program.