Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: space

From the Unemumerated blog, this piece was originally written in 1993:

Using materials native to space, instead of hauling everything from Earth, is crucial to future efforts at large-scale space industrialization and colonization. At that time we will be using technologies far in advance of today’s, but even now we can see the technology developing for use here on earth.

There are a myriad of materials we would like to process, including dirty organic-laden ice on comets and some asteroids, subsurface ice and the atmosphere of Mars, platinum-rich unoxidized nickel-iron metal regoliths on asteroids, etc. There are an even wider array of materials we would like to make. The first and most important is propellant, but eventually we want a wide array of manufacturing and construction inputs, including complex polymers like Kevlar and graphite epoxies for strong tethers.

The advantages of native propellant can be seen in two recent mission proposals. In several Mars mission proposals[1], H2 from Earth or Martian water is chemically processed with CO2 from the Martian atmosphere, making CH4 and O2 propellants for operations on Mars and the return trip to Earth. Even bringing H2 from Earth, this scheme can reduce the propellant mass to be launched from Earth by over 75%. Similarly, I have described a system that converts cometary or asteroidal ice into a cylindrical, zero-tank-mass thermal rocket. This can be used to transport large interplanetary payloads, including the valuable organic and volatile ices themselves into high Earth and Martian orbits.

Earthside chemical plants are usually far too heavy to launch on rockets into deep space. An important benchmarks for plants in space is the thruput mass/equipment mass, or mass thruput ratio (MTR). At first glance, it would seem that almost any system with MTR>1 would be worthwhile, but in real projects risk must be reduced through redundancy, time cost of money must be accounted for, equipment launched from earth must be affordable in the first place (typically

A special consideration is the operation of chemical reactors in microgravity. So far all chemical reactors used in space — mostly rocket engines, and various kinds of life support equipment in space stations — have been designed for microgravity. However, Earthside chemical plants incorporate many processes that use gravity, and must be redesigned. Microgravity may be advantageous for some kinds of reactions; this is an active area of research. On moons or other plants, we are confronted with various fixed low levels of gravity that may be difficult to design for. With a spinning tethered satellite in free space, we can get the best of all worlds: microgravity, Earth gravity, or even hypergravity where desired.

A bigger challenge is developing chemical reactors that are small enough to launch on rockets, have high enough thruput to be affordable, and are flexible enough to produce the wide variety of products needed for space industry. A long-range ideal strategy is K. Eric Drexler’s nanotechnology [2]. In this scenario small “techno-ribosomes”, designed and built molecule by molecule, would use organic material in space to reproduce themselves and produce useful product. An intermediate technology, under experimental research today, uses lithography techniques on the nanometer scale to produce designer catalysts and microreactors. Lithography, the technique which has made possible the rapid improvement in computers since 1970, has moved into the deep submicron scale in the laboratory, and will soon be moving there commercially. Lab research is also applying lithography to the chemical industry, where it might enable breakthroughs to rival those it produced in electronics.

Tim May has described nanolithography that uses linear arrays of 1e4-1e5 AFM’s that would scan a chip and fill in detail to 10 nm resolution or better. Elsewhere I have described a class of self-organizing molecules called _nanoresists_, which make possible the use of e-beams down to the 1 nm scale. Nanoresists range from ablatable films, to polymers, to biological structures. A wide variety of other nanolithography techniques are described in [4,5,6]. Small-scale lithography not only improves the feature density of existing devices, it also makes possible a wide variety of new devices that take advantage of quantum effects: glowing nanopore silicon, quantum dots (“designer atoms” with programmable electronic and optical properties), tunneling magnets, squeezed lasers, etc. Most important for our purposes, they make possible to mass production of tiny chemical reactors and designer catalysts. Lithography has been used to fabricate a series of catalytic towers on a chip [3]. The towers consist of alternating layers of SiO2 4.1 nm thick and Ni 2–10 nm thick. The deposition process achieves nearly one atom thickness control for both SiO2 and Ni. Previously it was thought that positioning in three dimensions was required for good catalysis, but this catalyst’s nanoscale 1-d surface force reagants into the proper binding pattern. It achieved six times the reaction rate of traditional cluster catalysts on the hydrogenolysis of ethane to methane, C2H6 + H2 –> 2CH4. The thickness of the nickel and silicon dioxide layers can be varied to match the size of molecules to be reacted.

Catalysts need to have structures precisely designed to trap certain kinds of molecules, let others flow through, and keep still others out, all without getting clogged or poisoned. Currently these catalysts are built by growing crystals of the right spacing in bulk. Sometimes catalysts come from biotech, for example the bacteria used to grow the corn syrup in soda pop. Within this millenium (only 7.1 years left!) we will start to see catalysts built by new techniques of nanolithography, including AFM machining, AFM arrays and nanoresists Catalysts are critical to the oil industry, the chemical industry and to pollution control — the worldwide market is in the $100’s of billions per year and growing rapidly.

There is a also big market for micron-size chemical reactors. We may one day see the flexible chemical plant, with hundreds of nanoscale reactors on a chip, the channels between them reprogrammed via switchable valves, much as the circuits on a chip can be reprogrammed via transitors. Even a more modest, large version of such a plant could have a wide variety of uses.

Their first use may be in artificial organs to produce various biological molecules. For example, they might replace or augment the functionality of the kidneys, pancreas, liver, thyroid gland, etc. They might produce psychoactive chemicals inside the blood-brain barrier, for example dopamine to reverse Parkinson’s disease. Biological and mechanical chemical reactors might work together, the first produced via metaboic engineering[7], the second via nanolithography.

After microreactors, metabolic engineering, and nanoscale catalysts have been developed for use on Earth, they will spin off for use in space. Microplants in space could manufacture propellant, a wide variety of industrial inputs and perform life support functions more efficiently. Over 95% of the mass we now launch into space could be replaced by these materials produced from comets, asteroids, Mars, etc. Even if Drexler’s self-replicating assemblers are a long time in coming, nanolithographed tiny chemical reactors could open up the solar system.

====================
ref:
[1] _Case for Mars_ conference proceedings, Zubrin et. al.
papers on “Mars Direct“
[2] K. Eric Drexler, _Nanosystems_, John Wiley & Sons 1992
[3] Science 20 Nov. 1992, pg. 1337.
[4] Ferry et. al. eds., _Granular Nanoelectronics_, Plenum Press 1991
[5] Geis & Angus, “Diamond Film Semiconductors”, Sci. Am. 10/92
[6] ???, “Quantum Dots”, Sci. Am. 1/93
[7] Science 21 June 1991, pgs. 1668, 1675.

These microreactors have a multiplicity of uses in various Lifeboat-relevant endeavors, including making human beings more resistant against harmful diseases. Molecular nanotechnology, rather than being long-range, is likely to be developed between 2010 and 2020. The Center for Responsible Nanotechnology has written at length in favor of this view.

The New Scientist also has an article about how exploding robots could be sent to determine the composition of Near Earth Asteroids. This would be relevant in developing a proper Asteroid shield. A current project is the Lifeboat AsteroidShield

An illustration from Ball Aerospace and New Scientist.

The Ball Aerospace proposal of many small probes seems cost efficient and worthy of being advocated by the Lifeboat Foundation.

The New Scientist discusses a recent study that advocates using of an ion beam generator on the moon to allow the use of far smaller rockets to move from the moon to other locations in space. The ion beam generator would need several hundred megawatts of electrical power from either a large solar cell array or nuclear power.

I have discussed the need on my website to make gigawatts of power on the moon and in orbit in order to begin serious development and colonization efforts.

An alternative to ion beams would be magbeam, a plasma based approach for accelerating spaceships

The Lifeboat Foundation supports space habitats and Asteroid shields

The beam approaches all require large power sources. The fastest way to achieve this would be to build a lightweight nuclear power source on the earth and launch it into a high orbit (a lagrange point) or the moon.

The power could also be used to power mining and industrial machinery on the moon which has uranium and thorium and the raw materials to make more nuclear reactors. Containment and waste issues on the moon would be less of an issue until colonization happened in a big way. The colonization is better place in rotating structures in orbit, so the moon could be a power and material source for primarily orbital colonization.

Large scale structures for solar power and for space stations could be made with mostly existing or near term technology using magnetically inflated cables Using superconducting wire a lightweight structure could be launched that would unpack from an existing rocket and then expand to be 1 kilometers in diameter or more.

The main points are large scale space architecture is possible in the near term. Large power sources are needed and can be built. We can create viable space habitats with large viable populations properly engineering the technology that we have now. This would be superior to the lunar program that NASA has proposed which lacks the scale necessary to establish viable Lifeboat colonies.

On CNN:

WASHINGTON (CNN) — China last week successfully used a missile to destroy an orbiting satellite, U.S. government officials told CNN on Thursday, in a test that could undermine relations with the West and pose a threat to satellites important to the U.S. military.

According to a spokesman for the National Security Council, the ground-based, medium-range ballistic missile knocked an old Chinese weather satellite from its orbit about 537 miles above Earth. The missile carried a “kill vehicle” and destroyed the satellite by ramming it.

The test took place on January 11. (Watch why the U.S. has protested the missile strike Video)

Aviation Week and Space Technology first reported the test: “Details emerging from space sources indicate that the Chinese Feng Yun 1C (FY-1C) polar orbit weather satellite launched in 1999 was attacked by an asat (anti-satellite) system launched from or near the Xichang Space Center.”

A U.S. official, who would not agree to be identified, said the event was the first successful test of the missile after three failures.

The official said that U.S. “space tracking sensors” confirmed that the satellite is no longer in orbit and that the collision produced “hundreds of pieces of debris,” that also are being tracked.

The United States logged a formal diplomatic protest.

“We are aware of it and we are concerned, and we made it known,” said White House spokesman Tony Snow.

Several U.S. allies, including Canada and Australia, have also registered protests, and the Japanese government said it was worrisome.

China’s leaders are merely acting in the country’s best interests. In any major conflict, the ability to knock satellites out of the sky could be invaluable. That is why the US is making such a fuss about this. The leaders of China are only human — and humans have the tendency to engage in arms races. What can be done to prevent the militarization of space? If you have ideas, give them in the comments.

Update: here’s another article from the BBC.

From Yahoo News:

Astrophysicist Stephen Hawking says he wants to undertake a zero-gravity flight aboard an aircraft this year as a precursor to a journey into space.

“This year I’m planning a zero-gravity flight and to go into space in 2009,” he was quoted as saying in The Daily Telegraph newspaper.

Hawking, 65, has said he hopes to travel on British businessman Richard Branson’s Virgin Galactic service, which is scheduled to launch in 2009. The service will charge space tourists about $US200,000 ($A257,000) for a two-hour suborbital trip 140 km above the Earth.

Branson was keen to help the scientist realise his dream of space flight, Virgin Galactic spokesman Stephen Attenborough said.

“Richard is very determined that if we can possibly make this happen, then it should,” Attenborough said.

He said the company had not discussed the issue of payment with Hawking.

One of the best-known theoretical physicists of his generation, Hawking gained fame with the best-selling book A Brief History of Time.

The scientist, who uses a wheelchair and communicates with the help of a computer because he suffers from a neurological disorder called amyotrophic lateral sclerosis, has done groundbreaking research on black holes and the origins of the universe, proposing that space and time have no beginning and no end.

Hawking has warned that the survival of the human race depends on its ability to find new homes elsewhere in the universe because there’s an increasing risk that a disaster will destroy Earth.

See you in orbit, Dr. Hawking!