By Greg Clark
Arizona Daily Wildcat
September 24, 1997

Space Dig

Photo Courtesy/SpaceDev Arizona Daily Wildcat This illustration shows the SpaceDev spacecraft approaching an asteroid near Earth to collect data. The device uses onboard instruments to assess the economic value constituting the asteroid.

If one doesn't catastrophically slam into Earth, the 400 or so asteroids in near-Earth orbit may be the claims of 21st century prospectors.

These asteroids may hold fortunes for those who would claim the orbiting bodies to mine for water and metals, said University of Arizona Professor and planetary scientist John Lewis.

Lewis works as consultant to SpaceDev, a private company that announced earlier this month it will build and launch a spacecraft to a near-Earth asteroid to stake a claim and prospect for valuable minerals.

Founded last year by James Benson, a Colorado entrepreneur who started two successful software companies, SpaceDev is attempting to make history by launching the first privately owned spacecraft.

Benson hopes to launch the Near Earth Asteroid Prospector in 1999 at a cost of $60 million, SpaceDev spokeswoman Susan Flowers said.

Benson has been raising money from private investors and is reportedly only $7 million short of necessary costs, Lewis said.

The Asteroid Prospector "will carry five scientific instruments to an asteroid to analyze its size, and determine its composition and value," Benson said in a press release.

One of those instruments will be an alpha proton X-ray spectrometer, the same instrument that allows Sojourner rover to analyze rocks on the surface of Mars, Lewis said.

SpaceDev will sell the space for the other four instruments to outside clients willing to pay for the ride. Potential clients include NASA, he said.

He believes the private sector can complete space missions at one quarter the cost of similar government programs.

Although detractors dismiss the idea of claiming property in space as far-fetched science fiction, others say the space trade of the coming century will be as significant as the spice trade 500 years ago.

The payoffs may be staggering, Lewis said.

There are more than 50 known metallic asteroids in near-Earth orbit, the metal in smallest of these would be worth $4 trillion on Earth, he said.

The solid block of space metal, one kilometer (.6 miles) in diameter and composed of iron, nickel, cobalt and even natural stainless steel, would be worth the equivalent of the gross domestic product of the United States, Lewis said.

"That single asteroid actually contains several times more metal than the combined total of all metals mined and processed on Earth in human history," he said.

Stony asteroids, which may be mined more easily than a solid crystal of stainless steel the size of Manhattan Island, Lewis said, may contain up to 30 percent metal.

The market for these metals is in space.

To build anything of any size in space, he said, materials must be available. It is not feasible to bring material from Earth into space.

"If you need to build anything of any strength in space, you need metal beams, girders, wires, nuts and bolts. We have developed some very simple techniques for making these low-tech structural members in space. The metals exist in great quantity on asteroids, we just need to identify them and extract them," Lewis said.

Producing construction materials in space is prerequisite of building large spacecraft and space stations, he said.

There are even plans to build solar power stations in orbit. Though the technology exists to collect power using orbiting arrays of solar collectors and transmit electricity to collecting stations on Earth via high-powered microwave, Lewis said, the cost of launching construction materials into orbit is prohibitive.

When it reaches its asteroid, the Prospector spacecraft also will be searching for water, from which space industrialists can make rocket fuel.

Lewis sees a lucrative market for rocket fuel in space.

Liquid hydrogen and liquid oxygen, the most common rocket propellants, can be electrolyzed from water.

Though these fuels cost only 30 cents per pint on Earth, they cost more than $6,000 per pint in space because of the expense of launching material into orbit, Lewis said.

The most efficient way to fuel spacecraft is to launch them with only enough fuel to reach low-earth orbit. They can then be refilled with fuel made in space at a fraction of the cost it would take to bring along all the fuel for an entire mission from the ground, he said.

Half of the near-earth asteroids may be extinct comet cores, which could be made of up to 60 percent ice. After finding such asteroids and claiming them, the next step would be to develop techniques for electrolyzing hydrogen and oxygen in space, something that now occupies the thinking of scientists like Lewis.