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Big Space vs. Little Space: Big and Expensive vs. Agile and Cheap

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Freeman Dyson has an interesting review in the NY Review of Books:

How to Make a Spaceship: A Band of Renegades, an Epic Race, and the Birth of Private Spaceflight
by Julian Guthrie
Penguin, 432 pp., $28.00

Beyond Earth: Our Path to a New Home in the Planets
by Charles Wohlforth and Amanda R. Hendrix
Pantheon, 320 pp., $27.95

All These Worlds Are Yours: The Scientific Search for Alien Life
by Jon Willis
Yale University Press, 214 pp., $30.00

Robert Dicke was an experimental physicist at Princeton University. He liked to build things with his own hands. When NASA began making plans for landing astronauts on the moon, he thought of a scheme that would allow the astronauts to make a serious contribution to science. This would be good for science and also good for the astronauts. The scheme was to measure accurately the distance between two objects, one fixed on Earth and the other fixed on the moon. The measurements would give us improved understanding of the dynamics of the Earth-moon system.

The object on Earth would be a laser emitting very short pulses of light. The object on the moon would be a tray holding a hundred corner-cube glass reflectors. A corner cube is a piece of solid glass cut so as to reflect light efficiently. The corner cubes would reflect the laser pulses back to the laser. The timing of the reflected pulses would measure the distance between the laser and the tray. The astronauts would plant the tray on a firm piece of ground on the moon facing Earth. Because the corner cubes reflect light straight back to its source, the small variations in the orientation of the moon as it moves in its orbit do not disturb the measurement.

Dicke was a practical person. He went to the Edmonds Scientific Company toy store down the road from Princeton and bought a hundred high-quality glass corner-cube reflectors for $25 each. He asked the machine shop at the Princeton University physics department to attach the cubes to a metal tray with a stand to support it. The complete package, including materials and labor, cost a total of $5,000. Then he got in touch withNASA officials and told them he would be happy to supply the package at this cost for a moon mission. The NASA officials accepted his proposal enthusiastically, but they said, “You do not get to build it. We get to build it.” The proposal to build the package was put through the normal bureaucratic NASA acquisition process. According to Dicke, NASA paid $3 million to an industrial contractor for it. The reflectors were duly installed on the moon and are still reflecting laser pulses as Dicke intended. Doing things the NASA way increased the cost by a factor of six hundred.

The moon missions happened long ago. Now, fifty years later, there is still a clash between two cultures. There is Big Space, with big corporations receiving contracts from NASA to produce custom-built hardware and software following NASAprocedures at enormous cost. And there is Little Space, aiming to carry out space operations in the Dicke style, using hardware and software mass-produced for other purposes by companies in a competitive market at vastly lower cost. The Big Space culture is still dominant, carrying out spectacularly successful high-cost missions, such as the Cassini mission that sent back detailed pictures of the satellites of Saturn, and the Kepler mission that discovered thousands of planets orbiting around other stars. But there are now several start-up companies operating independently of NASA in the Little Space culture, hoping to do space missions that will be bolder, quicker, and cheaper.

Will Marshall was a young engineer working in the Big Space culture at the Jet Propulsion Laboratory (JPL), a NASA center that builds big expensive spacecraft such as Cassini. He rebelled against that culture and decided to do things differently. Along with two other NASA alumni, he started his own company and built a satellite that he called Dove in his garage in Cupertino. The company then changed its name to Planet Labs and built 150 Dove satellites in a few years, with 150 more to be launched next year. His satellites are radically smaller and cheaper than anything built at the JPL, but they are equally well engineered and more agile. They belong to the Little Space culture, using modern miniaturized cameras and guidance systems and data processors, like those that are mass-produced for the cell phone and recreational drone industries.

A Dove satellite weighs about ten pounds and costs under a million dollars, including launch and operations and a communication system for distributing large amounts of information to the Planet Labs customers. The information consists of pictures of the ground taken from low earth orbit, with accurate color to show the type and condition of vegetation, with complete coverage of the planet every few days, and with “resolution”—the size of the smallest patches that can be seen in the picture—about ten feet. The customers are farmers looking at crops, foresters looking at trees, fire-control authorities looking at fires, environmentalists looking at pollution and erosion of land, and government officials at all levels looking at ecological problems and environmental disasters.

Marshall likes to describe how he lost twenty-six Dove satellites in 2014. They were sitting together on a big rocket that exploded on the launch-pad. The loss hardly affected his business, since he had had nine successful launches and only one failure. The lost satellites were quickly replaced and the replacements put in orbit. The great advantage of the Little Space culture is that every mission is cheap enough to fail. It makes a huge difference to the running of a business if failures are acceptable. Missions in the Big Space culture are too big to fail. In that culture they typically take a decade to plan and a decade to build. A Dove satellite is planned and built in a few months. Occasional failures in the Little Space culture are a normal part of the cost of doing business. If there are too many failures, the company running the business may collapse, but that is not an unacceptable disaster. Start-up companies evolve in a Darwinian ecology, where the fit survive and the unfit collapse.

Planet Labs and other start-up companies have proved that the Little Space culture is ready to take over a large share of future unmanned activities in space. The question remains open whether the Little Space culture can have a similarly liberating effect on manned missions. Can we expect to see manned missions becoming radically cheaper, so that we can travel with our machines at costs that ordinary people or institutions can afford? Neither Big Space nor Little Space shows us a clear path ahead to the fantasy worlds of science fiction, where bands of brave pioneers build homes and raise children among the stars.

Halfway between Big Space and Little Space, there is a group of companies that grew rapidly in recent years, led by SpaceX, a company founded in 2002 by Elon Musk. Musk is a young billionaire who has dreams of founding human colonies on Mars. His company builds big spacecraft paid for by big NASA contracts in the Big Space style, but he tries to keep the design and manufacture cheap and simple in the Little Space style. In ten years he has built a launcher, Falcon, and a transfer vehicle, Dragon, which ferry unmanned payloads from the ground to the International Space Station. He intends soon to include astronauts in his payloads. The SpaceX culture is a compromise, using commercial competition to cut costs while relying on the government for steady funding. The twenty-first century is likely to see manned missions exploring planets and moons and asteroids, and possibly making spectacular discoveries. But this century is unlikely to see costs of such missions low enough to open space to migration and settlement by ordinary citizens.

The three books under review describe space activities belonging to the Big Space and Little Space cultures that are now competing for money and public attention. Each book gives a partial view of a small piece of history. Each tells a story within the narrow setting of present-day economics and politics. None of them looks at space as a transforming force in the destiny of our species. . .

Continue reading. Later in the review:

. . . With Tsiolkovsky, we leave behind the parochial concerns of the twenty-first century and jump ahead to a longer future. In the long run, the technology driving activities in space will be biological. From this point on, everything I say is pure speculation, a sketch of a possible future suggested by Tsiolkovsky’s ideas. Sometime in the next few hundred years, biotechnology will have advanced to the point where we can design and breed entire ecologies of living creatures adapted to survive in remote places away from Earth. I give the name Noah’s Ark culture to this style of space operation. A Noah’s Ark spacecraft is an object about the size and weight of an ostrich egg, containing living seeds with the genetic instructions for growing millions of species of microbes and plants and animals, including males and females of sexual species, adapted to live together and support one another in an alien environment.

After the inevitable mistakes and failures, we will have acquired the knowledge and skill to build such Noah’s Arks and put them gently into suitable places in the sky. Suitable places where life could take root are planets and moons, and also the more numerous cold dark objects far from the sun, where air is absent, water is frozen into ice, and gravity is weak. The purpose is no longer to explore space with unmanned or manned missions, but to expand the domain of life from one small planet to the universe. Each Noah’s Ark will grow into a living world of creatures, as diverse as the creatures of Earth but different. For each world it may be possible to develop genetic and other instructions for growing a protected habitat where humans can live in an Earth-like environment. The expansion of human societies into the universe will be a small part of the expansion of life. After the expansion of life and the expansion of human societies have started, the new ecologies will continue to evolve in ways that we cannot plan or predict. The humans in remote places will then also have the freedom to evolve, so that they can move out of protected habitats and walk freely on the worlds where they have settled.

The essential new species, enabling Noah’s Ark communities to survive in cold places far from the sun, will be warm-blooded plants. A warm-blooded plant is a species with leaves and flowers and roots and shoots in a central structure, kept warm by sunlight or starlight concentrated onto it by mirrors outside. The mirrors are cold, separated from the warm center by a living greenhouse with windows that let the light come in but stop heat radiation from going out. The mirrors are attached to the greenhouse like feathers on a peacock. The mirrors and the greenhouse perform the same functions for a warm-blooded plant that fur and fat perform for a polar bear.

The entire plant, with the warm center and the greenhouse and the mirrors, must grow like a mammal inside its mother before it can be pushed out into the cold world. The new species of plants will be not only warm-blooded but also viviparous, growing the structures required for independent living while still inside the parent plant. To make viviparous plants possible, the basic genetic design of warm-blooded mammals must be understood and transferred to become a new genetic design for plants. Our understanding and mastery of genetic design will probably be driven by the needs of medical research, aimed at the elimination of disease from human, animal, and plant populations. Warm-blooded and viviparous plants will fill empty ecological niches on Earth before they are adapted for life support in Noah’s Arks. They may make Antarctica green before they take root on Mars.

Almost all the current discussion of life in the universe assumes that life can exist only on worlds like our Earth, with air and water and strong gravity. This means that life is confined to planets and their moons. The sun and the planets and moons contain most of the mass of our solar system. But for life, surface area is more important than mass. The room available for life is measured by surface area and not by mass. In our solar system and in the universe, the available area is mostly on small objects, on comets and asteroids and dust grains, not on planets and moons.

When life has reached the small objects, it will have achieved mobility. It is easy then for . . .

Written by LeisureGuy

25 September 2016 at 10:52 am

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