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Posts Tagged ‘Space’

It is logical to believe that there exist millions of planets in the “vicinity” of our part of the universe alone. However, limited due to tools and the extremely vast distances to be dealt with, we have only been to locate about 300 extra-solar planets, and these have been located indirectly. That is, by observing gravitational wobbles by tracking the star over a period of time it can be known if it is tugged at by an object like a planet.

Why is it difficult to Image the actual planets, one might ask? Well the reason is simple, the distances we deal with are so huge the star simply outshines the planet, making it very difficult to image the planets moving around the star. How does one avoid this problem? The idea is very practical. A occulting bar is used to block out the brightest part of the star’s image so that the blinding light is reduced. Other more specialized techniques can improve things by reducing the light further.

Also another strategy used by professional astronomers looking into deep space for planets over the last two decades has been to focus on systems expected around young stars. The reason being that if the formation of the planetary system is recent the planets would be significantly brighter from the heat of their formation. Much like our early solar system. It would be very difficult to look into space for a planet that is nestled in a star system like that of our Sun of today. This is because the planets would be very very faint (as they would be older and hence colder) and hence very very difficult to image.

However for the first time we have ACTUALLY been able to see extra-solar planets. This is a HUGE step, culminating from years of painstaking observations and focus. These planets are gaseous and probably will have no trace of life. However, the fact that we have been able to image them has a LOT of meaning. Some astronomers have said that it might not be very fantastic to think that we might in a very short time vector be able to observe some Earth like planet that is more likely to have life (carbon based, atleast of the type we know), now this is something that one could not even THINK of some years ago. It was probably fantasy to think we could be able to image planets like our own, now suddenly it looks quite possible.

The first image below, taken by the Hubble telescope shows a ring of dust surrounding the star Fomalhaut (derived from the Arabic فم الحوت fum al-ḥawt, meaning “mouth of the whale”) which is only 25 light years away in the constellation Piscis Australis. This star can be seen with the naked eye in the night sky. The lower right inset image is a composite image from the images taken in 2004 and 2006. Paul Kalas and his team of the University of California at Berkeley found out the planet.  This planet completes orbit around its star every 872 years.

fomalhaut[Image Source: HubbleSite]

The radial streaks are scattered starlight. The planet’s temperature is 260 degrees, quite cool compared to other exoplanets. This dot is about three times the weight of Jupiter and about three times as far from the star as compared to how far Pluto is from our sun. This dusty ring around Fomalhaut is suspected to be something like the Kuiper belt of our solar system.

This star system was expected to have planets in 2005.

The following is a video on the same:

A ring of dust surrounds the star Fomalhaut. Images taken with the Hubble Space Telescope in 2004 and 2006 show that a white dot just inside the dust ring moved in the intervening two years. Researchers believe the dot is a planet that weighs no more than 3 Jupiter masses and lies about three times as far from its star as Pluto does from the Sun (Courtesy of Paul Kalas/UC Berkeley)

Yet another fantastic finding was the discovery of a planetary trio orbiting the star HR 8799 in the constellation pegasus. About 130 light years away, the planets found are from 7-10 times the size of jovian Jupiter. With the farthest of the lot sitting at a distance of 68 AU from HR 8799 (1 AU is the distance between the earth and the Sun). These planets are still glowing because of the heat resulting from contraction after their formation. Their orbit was measured by far IR techniques at the Keck and Gemini North telescopes in Hawaii.

hr-8799

This near-infrared composite image shows the nearby star HR 8799 (multi-coloured blob) and its three planets (red dots at upper left, upper right and just below the star). The planets are 7 to 10 times as massive as Jupiter (Image: National Research Council Canada).


Wow! I am awed once again by the ability of astronomers to find out even the most obscure of dots amongst a nasty conundrum of dots. And even more by the discovery itself. And let me not talk about the images we have above.

I have always harbored a fantasy, that is to be on the crew of humans who get to travel to such a far off land on a Super Daedalus or Super Orion type space-ship. It would take some years (space-ship time). But ofcourse when I return to Earth I would not find anybody I know. For, centuries would have passed as per Earth time by the time I get back. ;)

Onrionesque Reality Home >>

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The first Indian lunar probe the Chandrayaan I (in sanskrit, संस्कृतम् Chandra = moon ; Yaan = Vehicle . So, literally it means moon craft) beamed back its first pictures of the earth that it took as the ISRO (Indian Space Research Organization) has been testing the cameras on Chandrayaan.

The terrain mapping camera aboard Chandrayaan, which is a black and white imager, had been turned on for testing. It relayed back two test images, one taken at a height of 3,000 km and the other at a height if 70,000 km. The Pictures can be found and viewed in higher resolution here.

Update (15 November): Chandrayaan has now started sending pictures from the Moon,  this post was written only for the pictures sent back of the Earth while testing the terrain mapping camera. Find them at the end of this post.

[Pictures of home never grow old ]

Click to Enlarge

The Chandrayaan was launched on the 22nd of October by India’s old warhorse the PSLV (C11) into an initial elliptical orbit around the Earth. Like many I was skeptical about the logic for such a mission when it was announced a few years ago. I just thought there was no real logic in doing an exercise that would essentially be a re-invention of the wheel. Over time my view refined by more information about it has changed. I will come back to this in just about a while.

Ofcourse one would say anything to do with space research is a show of a countries growing economic clout and it commands immediate respect. True, but that is not why I think it is not a futile exercise.

Inexpensive, So why not do it? Some argue that though India is growing rapidly and is projected to over take many major European economic powerhouses by 2015-2020 (It is already ahead of them in PPP terms though still has a long way to go in nominal GDP terms) and countries like Japan by the 2030-35, it still has a lot of people under the poverty line and the standard of living remains low. So it is only a waste of money. Well, the Chandrayaan I only cost $80 million, the cheapest moon mission of comparable scales by far. And this much money is meager when you look at an elephant like economy really (to give you an idea, the Boeing 747-8 costs US$285.5-300 million according to 2007 prices. So the mission that way cost nothing really, so the whole talk about India wasting money has very little ground.

To Avoid a Possible Space Apartheid: The NPT is always billed as an unfair treaty by three nations that refuse to sign it – India, Israel and Pakistan. Their argument being that the provision of the treaty that allows the countries that made atomic weapons before 1967 to keep weapons, and to continue their development and to disallow and to impose sanctions on countries that try to develop weapons later is unfair, and there is no reason stated why such a distinction is made. India has advocated disarmament as a complete solution.

Anyway, I have always thought that an international agency should hold a minimum number of weapons and all the other countries should give up their nuclear weapons over time. This reserve should be kept only for a very unlikely doomsday scenario in the future that might require mankind (stress added) to intercept a comet on collision path towards the Earth with an Orion like super missile. This is extremely unlikely, but one can never totally rule out the chance even in a medium term time vector.

Coming back, if in a similar manner, in the medium term future there is a possibility of some select countries to set up a base on Mars or on the Moon, then it is possible that countries who made a mark in space till a specific date might only get to join. And it might just end up being like the NPT. So making a mark is a wise thing to do. Though again this is a sort of an outlandish argument.

Now coming back to the main argument that was it worth it to send a mission that is like doing boldly what others have done before. What new is left on the moon to be looked at, absolutely nothing? I think it is not something like that, and it is definitely worth it. Let’s get a sense of history first to see why.

A Little History: The Moon always has been an object of wonder since the stone age man. Many rock paintings have featured the moon. Over the ages people have looked up with amazement on what it was and what was on it. Most religious beliefs accorded it to be an immutable creation of God and some gave the Moon the status of god.

This notion was first challenged in recorded history by the observations of the Canterbury Monks in 1178 (June 18), who recorded an explosion on the moon, which was in recent times confirmed as a comet striking the moon. By the middle ages it was fairly recognized that the moon was a sphere though mostly it was held that it had a smooth surface. The heretic Galileo Galilei was the first to draw images of the moon that challenged this view. Clearly, the telescope was the first giant leap in the exploration of the moon. Over time it was recognized that the moon had a surface as terrestrial as on Earth and that there was nothing heavenly about the moon. For some centuries for the want of tools, there continued to be speculations about the nature of moon and life on it.

Speculations are always a part of any space exploration or thought process, they only aid in further development of tools to explore them, the present one being speculations (though more studied and calculated than the ones we had 500 years ago ofcourse)  about water or He3 on the moon. The absence of tools gave rise to wild speculations like in the great moon hoax of 1835 a number of people were led to believe that there were strange beings living on the moon.

The era of modern exploration of the moon began with the Luna 1 (also Mechta : Russian word meaning Dream) of the former Soviet Union.

[The Luna 1]

It was the first human made object to reach the vicinity of the moon. The subsequent cold war race between the Soviet Union and the US culminated in 1969 with the landing of the first humans on the moon. Till then they had sent about 40 spacecrafts to map and study the lunar surface in great detail. After the first moon landing about a dozen men landed on the moon. They were as follows:

Apollo 11 [July 20, 1969]:
1. Neil Armstrong “One small step for (a) man, One giant leap for mankind…”
2. Buzz Aldrin

Apollo 12 [November 19-20, 1969]:
3. Pete Conrad
4. Alan Bean

Apollo 14 [February 5-6, 1971]:
5. Alan Shepard
6. Edgar Mitchell

Apollo 15 [July 31-August 2, 1971]:
7. David Scott
8. James Irwin

Apollo 16 [April 21-23, 1972]:
9. John W. Young
10. Charles Duke

Apollo 17 [December 11-14, 1972]:
11. Eugene Cernan
12. Harrison Schmitt

The Soviets mainly relied on robotic explorers to collect rock samples whereas the above astronauts got about 400 kg of soil and rock samples back to earth for investigation. After the end of this race the interest in the moon significantly waned. Was there anything left to know about the moon that would interest us at all?

Moon Mysteries:

>> Though we know the maximum about the moon as compared to any other celestial body other than our own planet, we still know very little about it.

>> The Moon is 4.5 billion years old and is a witness to the countless mysteries about the solar system we are not aware of. It still has a lot to offer. And its proximity would only help us in this quest.

>> Comprehensive lunar surveyors like the Clementine gave us a lot of new insight, but a lot remains to be known.

>> The origins of the moon are not known well enough. According to one hypothesis that has maximum currency today is that a large object collided with the Earth and resulted into debris that eventually formed the Moon.

How the Chandrayaan is Not A Reinvention of the Wheel:

1. The chief advantage that the Chandrayaan has is that it carries instruments that can survey the Moon in extensive detail like never before. This could lead to various new insights. It could map the Moon using the visible, UV, IR, X-Ray, Low Power Gamma ray and radar. This would give a detailed 3-D atlas of the moon and also a sound picture of its chemical composition.

The probe is expected to orbit the moon for two years, in this period if suppose there is a solar flare, then the x-rays emitted from the Sun could cause the iron on the Moon to emit characteristic X-rays which could be analysed by the Imaging X-Ray spectrometer. Also, this data could be used by the Hyper Spectral Imager and the Moon Mineralogy mapper to find out the amount of Iron on the Moon.

2. Water on the permanently shadowed regions of the poles of the Moon was a distinct possibility that was indicated by the Clementine mission, the Chandrayaan could go a long way in investigating this further.

3. There are many other objectives that the Chandrayaan is expected to work at.

For more details look here

Update (15th November): Chandrayaan has now started sending back images of the Moon and some have been released by the ISRO. They can be found over here:

One of them below was taken by the TMC in orbit.

tmc-polar-region-Moon-Chandrayaan

[Photo Source: Indian Space Research Organization ]

Click to Enlarge

In conclusion, one thing is for sure. World competition for space is now a thing of the past IMHO and space agencies around the world would only co-operate for working towards the overall benefit of mankind.

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I started writing this post on 18 June with the singular aim of posting it by 22 June. The objective of this post was to celebrate the life and ideas of Tommy Gold (May 22, 1920 – June 22, 2004) on his fourth death anniversary. But after that I did not have much access to the Internet for reasons I had posted about earlier, and so sadly I missed that date. After that I did not edit and post it as I thought there would be little point. Now I think it is okay to  post it instead of deleting it all together. A tribute to Thomas Gold would still be the aim though I regret I could not post in time.

[Image Source]

Quoting Thomas Gold (Source):

New ideas in science are not always right just because they are new. Nor are the old ideas always wrong just because they are old. A critical attitude is clearly required of every scientist. But what is required is to be equally critical to the old ideas as to the new. Whenever the established ideas are accepted uncritically, but conflicting new evidence is brushed aside and not reported because it does not fit, then that particular science is in deep trouble – and it has happened quite often in the historical past. If we look over the history of science, there are very long periods when the uncritical acceptance of the established ideas was a real hindrance to the pursuit of the new. Our period is not going to be all that different in that respect, I regret to say.

This paragraph reminds me of a post on Gaping Void, a blog that I just discovered two days back on the fantastic Reasonable Deviations. The post, titled Good Ideas Have Lonely Childhoods is highly recommended to read, as a vast majority of good ideas are heretical and this post is on a heretic. Infact this post on Gaping Void prompted me to publish this forgotten draft!

Thomas Gold was a true renaissance man, a brilliant polymath and a controversial figure who Freeman Dyson has described as a modern heretic. Gold was born as an Austrian and was educated in Switzerland and the UK, Initially he worked with Hermann Bondi and Fred Hoyle and then later accepted an appointment with the prestigious Cornell University and remained there till his death.

Gold portrays the typical rebel scientist, with a penchant for controversy and working against general and strongly held theories. Gold worked across a large number of fields- Cosmology, Biophysics, Astrophysics, Geophysics, Space Engineering etc. Throughout his career Gold never cared about being wrong or of the opposition. He had this knack of turning out to be right. He however was not afraid to be wrong, infact he has been very famously wrong two times and he took both times in good humor. Such was his intellect that he never cared of any opposition and his ideas have always been very interesting. I hope to chronicle some of his major ideas here.

Coming back, as I said he has been famously wrong two times:

1. First was the steady state theory. Gold along with Fred Hoyle and Hermann Bondi developed and published the steady state theory of the universe in 1948. The three thought that it was impossible to think that all of matter could be created out of an initial singularity. The theory proposed that new matter is created continuously and this accounts for the constant density of the expanding universe. Though this seems to have violated the first law of thermodynamics the steady state had a number of supporters in the 50s and the 60s but the discovery of the cosmic background radiation which basically is a remnant of the big bang or explosion was the first major blow to it and over time its wide acceptance declined to only a very few cosmologists like Jayant V. Narlikar, who very recently have proposed alternatives and modifications to the original idea of steady state like the quasi steady state. However whatever said and done, the competition between the Big Bang and the Steady State spurred a lot of research which ultimately has helped us understand the cosmos better as good competition always does.

2. His second major incorrect idea was proposed in 1955, when he said that moon’s surface was covered with a fine rock powder that is electro-statically supported. He later said that astronauts would sink as soon as they landed on the moon. His theory influenced the design of the American Surveyor lunar landing probes to a very large extent. But their precautions were excessive and most of the fears were unfounded, though when the Apollo 11 crew bought back soil samples from the moon, it was indeed powdery though nowhere close to the extent Gold had proposed it to be. However a lot of astronomers credit a lot of development in planetology in subsequent years to Gold’s initial work and ideas on the lunar regolith.

[The famous photo of the footprint on the Lunar Surface: The Lunar soil was powdery as predicted by Gold but nowhere to the extent he had thought so. Image Source : Wikipedia Commons]

On both the occasions Gold took “defeat” in good humor, the trademark of a good scientist is that he is never afraid to be wrong. He once remarked:

Science is no fun, if you are never wrong!

In choosing a hypothesis there is no virtue in timidity and no shame in sometimes being wrong.

The second quote is not supposed to be humorous by the way.

On most occasions however, Thomas Gold had this knack of turning out to be right inspite of facing intense criticism initially. Some of his heretical ideas that turned out right were:

1. Pitch Discriminative Ability of the Ear: One of the first of Tommy Gold’s ideas that was received with much hostility and was summarily rejected by the experts of the time was his theory and experiments on hearing and pitch discrimination. In 1946 immediately after the great war, Gold got interested in the ability of the human ear to discriminate the pitch of musical sounds. It was a question that was perplexing the auditory physiologists of the time, and Gold fresh from working with the royal navy on radars and communications thought of the physiology of hearing in those terms. The human ear can tell the difference when a pure tone changes by as little as one percent. Gold thought that the ear contained a set of resonators finely tuned, whereas the prevailing view of the time was that the internal structure of the ear was too weak and flabby to resonate and all the interpretation of the sounds and tones happened in the brain, with the information being communicated by neural signals.

Gold designed a very simple and elegant experiment to prove the experts, the professional auditory physiologists wrong. The experiment has been described by Freeman Dyson in his book, The Scientist as Rebel as he himself was a part of the experiment. Prof Freeman writes:

He (Gold) fed into the headphones a signal consisting of short pulses of a pure tone, separated by intervals of silence. The silent intervals were atleast ten times as long as the period of the pure tone. The pulses were all of the same shape, but they had phases that could be reversed independently….Sometimes Gold gave all the pulses the same phase and some times he alternated the phases so that the even pulses had one phase and the odd pulses had the opposite phase. All I had to do was to sit with the headphones on my ears and listen while Gold put in the signals with either constant or alternating phases. I had to tell him from the sound whether the phase was constant or alternating. When the silent intervals between pulses was ten times the period of the pure tone, it was easy to tell the difference. I heard a noise like a mosquito, a hum and a buzz sounding together, and the quality of the hum changed noticeably when the phases were changed from constant to alternating. We repeated the trials with longer silent intervals. I could still tell the difference, when the silent interval was as long as thiry periods.

This elegant experiment showed that the human ear could remember the phase of a signal after it has stopped for thirty times the period of the signal and proved that pitch discrimination was done not in the brain but in the ear. To be able to remember the phase, the ear should have finely tuned resonators that continue to vibrate during the period of silence.

Now armed with experimental evidence for his theory that pitch discrimination was done in the ear, Gold also had a theory on how there could be very finely tuned resonators made up of the weak and flabby material in the ear. He proposed that the ear involved an active – not a passive – receiver, one in which positive feedback, not just passive detection is involved. He said that the ear had an electrical feedback system, the mechanical resonators are coupled to the electrically powered sensors so that the overall system works like an active tuned amplifier. The positive feedback would counteract the dissipation taking place in the flabby internal structure of the ear.

Gold’s findings and ideas were rejected by the experts of the field, who said Gold was an ignorant outsider with absolutely no knowledge or training in physiology. Gold however always maintained he was right. Thirty years later, auditory physiologists armed with more sophisticated tools discovered that Gold was indeed correct. The electrical sensors and the feedback system in the ear were identified.

Gold’s two papers on hearing published in 1948 remain highly cited to this day.

2. Pulsars: One of his ideas that was rather quickly accepted was his idea on what a Pulsar was. After being discovered by radio astronomers Gold proposed that they were rotation neutron stars.

[A schematic of a Pulsar. Image Source: Wikipedia Commons]

After some initial disapproval this idea was accepted almost immediately by the “experts”. Gold himself has written this on this matter in an article authored by him titled The Inertia of Scientific Thought:

Shortly after the discovery of pulsars I wished to present an interpretation of what pulsars were, at this first pulsar conference: namely that they were rotating neutron stars. The chief organiser of this conference said to me, “Tommy, if I allow for that crazy an interpretation, there is no limit to what I would have to allow”. I was not allowed five minutes floor time, although I in fact spoke from the floor. A few months later, this same organiser started a paper with the sentence, “It is now generally considered that pulsars are rotating neutron stars”.

3. The Arrow of Time: In the 60s Gold wrote extensively on The Arrow of Time, and held the view that the universe will re collapse someday and that the arrow of time will reverse. His views remain controversial till today and a vast majority of cosmologists don’t even take it seriously. It remains to be seen if Gold’s hypothesis would be respected.

4. Polar Wandering: In the 1950s while at the royal observatory, Gold became interested in the instability of Earth’s axis of rotation or the wandering pole. He wrote a number of papers on plasmas and magentic fields in the solar system and also coined the term “The Earth’s Magnetosphere”. In 1955 he published yet another revolutionary paper “Instability of the Earth’s Axis of Rotation“. Gold made the view that large scale polar wandering could be expected to occur in relatively short geological time spans. That is, he expressed the possibility that the Earth’s axis of rotation could migrate by 90 degrees in a time of under a million years. This effectively means that in such a case, points at the equator would come to the poles and points at the poles would come at the equator. Gold argued that this 90 degree migration would be triggered by movements of mass that would cause the old axis of rotation to become unstable. A large accumulation of ice at the poles for example might be one reason why such a flip could occur. His paper was ignored largely for over 40-45 years, largely because at that time the research was focused on plate tectonics and continental drift.

In 1997 a Caltech professor Joseph Kirschvink, who is an expert in these areas published a paper that suggested that such a 90 degree flip indeed happened at least once in the past in the early Cambrian era. This holds much significance given the fact that this large scale migration of the poles coincides with the so called “Cambrian Explosion“. Gold’s work was finally confirmed after being ignored for decades.

5. Abiogenic Origin of Petroleum: When I first read about the theory of abiogenic origin of petroleum promoted by Tommy Gold and many Soviet and Ukrainian Geologists, I was immediately reminded of my old organic chemistry texts that spoke of the abiogenic origin theory given by Mendeleev almost 150 years ago. This was called Mendeleev’s Carbide Theory and it died after the biological theory of petroleum origin was widely accepted.

Speaking as a layman who has little knowledge of geology, petroleum etc, I would say any theory of petroleum origin must broadly explain the following points:

1. Its association with Brine.

2. Presence of N and S compounds.

3. Presence of biomarkers, chlorophyll and haemin in it.

4. It’s optically active nature.

According to Mendeleev’s Carbide theory:

1. The molten metals in the Earth’s interior combined with carbon from coal deposits to form the corresponding carbides.

  • Ca + 2C ---> Ca C_2
  • Mg + 2C---> Mg C_2
  • 4Al + 3C---> Al_4 C_3

2. The carbides reacted with steam or water under high temperature and pressure to form a mixture of saturated and unsaturated hydrocarbons.

  • Ca C_2 + 2H_2 O---> Ca(OH)_2 + C_@ H_2
  • Al_4 C_3 +12H_2 O---> 4Al(OH)_3 +3C H_4

3. The unsaturated hydrocarbons underwent a series of reactions such as hydrogenation, isomerisation, polymerisation and alkylation to form a number of hydrocarbons.

  • C_2 H_2 ---> C_2 H_4 ---> C_2 H_6
  • 3[C_2 H_2]---> C_6 H_6

etc.

This theory got the support by the work of Moissan and Sabatier and Senderen. Moissan obtained a petroleum like liquid by the hydrogenation of Uranium Carbide, Sabatier and Senderen obtained a petroleum type substance by the hydrogenation of Acetylene.

However the theory was in time replaced by the theory of biological origin as it failed to account for:

1. The presence of Nitrogen and Sulphur compounds.

2. Presence of Haemin and Chlorophyll.

3. Optically active nature.

After almost hundred years, the abiogenic theory was resurrected by the great Russian geologist Nikolai Alexandrovitch Kudryavtse in 1951. This was worked on extensively by a number of Russians in the coming two decades.

In the west Thomas Gold was the only major proponent of it. And this is his most controversial theory, not only because it was opposed by powerful oil industry lobbyists but also because Gold faced much flak for plagiarism, something that Gold refused to acknowledge, in his later works he cited the works of the Russian scientists in the field. He maintained that he was simply not aware of the work done by the Soviet Geologists and that he cited their work once he became aware of it. Gold proposed that the natural gas and the oil came from reservoirs from deep within the Earth and are simply relics of the formation of the Earth. And that the biological molecules found in them did not show they had a biological origin but rather that they were contaminated by living creatures. He remained critical of the proponents of the theory of biological origin as then it could not be explained why there were hydrocarbon reserves on other planets when there had been no life on them. This theory remains controversial, Gold could not live to defend it. However an elegant experiment performed provides some evidence that Gold could indeed again be right.

Dyson wrote the following on an EDGE essay in this regard:

Just a few weeks before he died, some chemists at the Carnegie Institution in Washington did a beautiful experiment in a diamond anvil cell, [Scott et al., 2004]. They mixed together tiny quantities of three things that we know exist in the mantle of the earth, and observed them at the pressure and temperature appropriate to the mantle about two hundred kilometers down. The three things were calcium carbonate which is sedimentary rock, iron oxide which is a component of igneous rock, and water. These three things are certainly present when a slab of subducted ocean floor descends from a deep ocean trench into the mantle. The experiment showed that they react quickly to produce lots of methane, which is natural gas. Knowing the result of the experiment, we can be sure that big quantities of natural gas exist in the mantle two hundred kilometers down. We do not know how much of this natural gas pushes its way up through cracks and channels in the overlying rock to form the shallow reservoirs of natural gas that we are now burning. If the gas moves up rapidly enough, it will arrive intact in the cooler regions where the reservoirs are found. If it moves too slowly through the hot region, the methane may be reconverted to carbonate rock and water. The Carnegie Institute experiment shows that there is at least a possibility that Tommy Gold was right and the natural gas reservoirs are fed from deep below. The chemists sent an E-mail to Tommy Gold to tell him their result, and got back a message that he had died three days earlier.

6. The Deep Hot Biosphere: I am yet to read this book, though I have been thinking of reading it for almost a year now.

[The Deep Hot Biosphere, Image Source : Amazon]

In this controversial but famous theory Gold proposes that the entire crust of the Earth uptill a depth of a few miles is populated by living creatures. The biosphere that we see is only a very small part of it. The most ancient part of it is much larger and is much warmer. In 1992 Gold referred to ocean vents that pump bacteria from the depth of the Earth in support of his views. A number of such hydrothermal vents have since then been discovered. There is increasing evidence that his yet another controversial theory might just be right. Even if it is not, the evidence collected will help us understand our planet much better.

[A Black Smoker Hydrothermal Vent]

Finally Quoting Prof Freeman Dyson on him again:

Gold’s theories are always original, always important, usually controversial, and usually right.

References and Recommended Reads:

1. The Scientist as Rebel : Chapter 3 – Freeman Dyson (Amazon)

2. The Inertia of Scientific Thought – Thomas Gold

3. The Deep Hot Biosphere – Thomas Gold

4. Heretical Thoughts about Science and Society – Freeman Dyson

Onionesque Reality Home >>

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I dedicated some of the previous articles to the Orion Project only. I tried to briefly review the old project, its demise, then the new designs that have been put forth, and then put a personal opinion on what the problems are with Orion like projects without discounting the obvious advantages.

This video is more of a historical prospective to the Project. Makes a fascinating view!

In this TED talk:

George Dyson tells the amazing story of Project Orion, a massive, nuclear-powered spacecraft that could have taken us to Saturn in five years. With a priceless insider’s perspective and a cache of documents, photos and film, Dyson brings this dusty Atomic Age dream to vivid life.

(Text from the caption to the TED talk )

George Dyson is the son of the celebrated thinker, mathematician and physicist Freeman Dyson. George is a historian and a philosopher of science.

Onionesque Reality Home >>

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For fans of the dated Orion and Orion like projects there is some hope though. :)

It is in the form of the Mini-Mag-Orion. It tries to address some issues with the old model and uses modern techniques for simulation as well.

The detailed report can be found as a pdf here (Andrews Space)

A quick summary of this paper:

It – if it becomes reality – can give us the entire solar system with travel times to Mars of a couple of months and to Jupiter in less than a year. In it you compress SMALL pieces of fissionable material (curium245 or uranium 235 or uranium233 or plutonium 239) with the aid of a pulsating super-strong electromagnetic field so that their small masses compressed into ultra-small volumes become supercritical and explode. They explode INSIDE a superconducting magnetic rocket nozzle. One explosion per second.

Onionesque Reality Home >>

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The Project Orion still has iconic status in the eyes of many to this day, and i will not conceal the fact that the notion really had fascinated me when i first read of it in a newspaper years ago in a passing reference in a much bigger article on the space age. My eyes lit up and i started imagining how space travel could change (or rather could have!). ;)

Though i was planning to continue to write on Swarm Intelligence based routing for some more articles and then was thinking of going to dynamic programming and speech recognition. I decided that i would write on the Orion first. I hope to dedicate the next three or four posts only on this milestone project!

The video below is an excellent BBC excerpt from “To Mars by A-Bomb” (2003) showing some footage of the tests during the Orion years with some commentary from Freeman Dyson (who also happens to be a man i greatly venerate and is one of my heroes!) and Arthur C Clark. This is a rather short video! Do have a look!

I would give a short introduction to those who are not familiar with Orion.

We are used to space-ships using conventional fuels. For rating the efficiency of such fuels one parameter is Specific Impulse. It is stated in seconds and it indicates how many kilograms of thrust are obtained by the consumption of one Kg of the propellant in one second. This value is more or less characteristic of the type of propellant used, however there can be variations due to operating conditions and engine design. Therefore the higher the specific impulse the lesser the propellant is needed to gain a given amount of thrust.

Stanislaw Ulam in 1947 proposed Rocket propulsion using nuclear explosions, or pulsed nuclear explosions. He realized that nuclear explosions had not yet been contained in a combustion chamber. So instead it was proposed that the Orion design would work by dropping fissionable explosives out of the rear of the vehicle and catching the blast with a thick metal pusher plate.

The key components of the Orion are as in the figure.

Orion Design

Photo Courtesy: NASA Archives

The project initiated in 1958 under Ted Taylor and Freeman Dyson. This was the first such think tank assembled since the Manhattan Project. Orion offered both very high thrust and very high specific impulse. The potential it offered was enormous, Freeman Dyson has been quoted as saying that a single mission could provide with a permanent moon base and that it was possible to fly to and return back from Pluto in under one year. The orion could touch speeds upto 0.1 c according to some estimates and could carry as large as 8 million tons of mass, which could be as big as a city!!

The project died, due to concerns with the fallout due to each launch. Though Dyson maintained that conventional explosives could be used for launching the Ship out of Earth’s atmosphere and then nuclear fuel would take over. The Partial Test Ban Treaty of 1963 is said to have killed the project.

Even though the project died it was significant for its time in terms of stimulating possible engineering concepts.

Related Posts on this Blog:

1. Possible Rebirth of Project Orion?

2. Problems with Orion like projects

3. George Dyson on Project Orion

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