Space: Pros And Cons of a Flight to Mars

For years, U.S. and Soviet space scientists have agreed that Mars is a tantalizing target for exploration. Fragmentary data suggest that the planet may once have possessed a denser atmosphere, a warmer climate and even bodies of water. Many questions about life on Mars remain unanswered. So when Mikhail Gorbachev again declared only days before the Moscow summit that the U.S. and Soviet Union should “cooperate on a flight to Mars,” ears perked up in labs and offices from Los Angeles to Moscow. Even the Reagan Administration, which has balked at similar Soviet overtures, was at pains not to dismiss out of hand Gorbachev’s conciliatory-sounding proposal.

Despite the obvious allure of Gorbachev’s space suggestion, which will be formally presented to President Reagan this week in Moscow, U.S. experts in and out of Government are ambivalent about the feasibility of an actual joint expedition to Mars. At best, they point out, the success of any joint mission would rest on the fragile foundation of the Soviet leader’s revival of detente with the West. Could good relations between the superpowers, they ask, last long enough to complete, say, a ten-year project? “There are potential benefits to us from such a mission,” says U.S. Space Watcher Nicholas Johnson. “But there is great uncertainty about the political environment.”

While the General Secretary left the details vague, Soviet and American space scientists have long discussed the broad outlines of a joint mission. The most probable venture, an unmanned mission in 1998 to bring Martian soil back to earth, would blend the strengths of the two nations’ space programs. “The Soviets have the ability to put massive amounts of material into space,” says John McLucas, a NASA adviser and a former Secretary of the Air Force. “But they rely on other countries to supply a good fraction of their instrumentation. We do things in a more refined way and get better data.”

As now envisioned, the mission to collect samples would require separate U.S. and Soviet launches. With their heavy-lift launcher Energia, which can boost payloads at least three times as great as those on the U.S. shuttle, the Soviets would provide an extra capability to ensure sufficient backup fuel supplies. They believe they can deploy a space shield or parachute to slow their spacecraft enough to enable it to enter orbit around Mars without the use of retrorockets that draw on precious fuel supplies. Soviet scientists concede that this “aerobreaking” technique is still experimental.

The major U.S. contribution would be an “intelligent” ground vehicle. The robot rambler, which resembles the “moon buggy” used in the Apollo moon landings, would be used to gather and analyze soil samples. It must be able to find its way around the Martian surface, guided by an advanced artificial- intelligence “brain.” It would then deposit the soil samples in a special canister that would be blasted aloft to the Soviet orbiter for the trip home. The 1976 U.S. Viking Lander probes, by contrast, could only radio data from soil samples back from Mars. This time, the samples would be returned to earth aboard the Soviet craft after a period of quarantine, possibly aboard an earth-orbiting space station. Says a NASA official: “It’s a scheme that has a lot of attractive aspects.” Estimated cost to the U.S.: a cool $2.5 billion and six years of prelaunch labor. The round-trip mission itself would take two years.

The scenario, however, has its detractors. For starters, Reagan Administration officials are concerned about giving away valuable high-tech secrets. And though work on the robot rover is under way at the Jet Propulsion Laboratory in Pasadena, Calif., the machine is several years away from being ready for such a mission. Besides, notes McLucas, “there are language problems, cultural problems. Management is much more difficult with more parties getting into the act.” Nonetheless, M.I.T. Planetary Physicist Gordon Pettengill believes such a mission should be technically feasible “before 1998.”

Even so, there are other, more formidable barriers. Past cooperative space ventures have been closely tied to politics. The 1975 Apollo-Soyuz mission, for example, sprang from an earlier era of detente. The costly linkup between the orbiting U.S. and Soviet capsules (price tag: $300 million) was promoted to test compatible docking systems but had little scientific value: the flight was the last for the Apollo program. Prospects for more joint missions disappeared in December 1979, when the Soviets invaded Afghanistan. “These missions start for policy reasons and stop for political reasons,” says Nancy Lubin, a Government expert in U.S.-Soviet space cooperation. States NASA Administrator James Fletcher flatly: “Any major expenditure of money is not likely. We couldn’t do much more than study the thing.”

Although the case for a joint mission may be compelling to some, both scientists and Government officials are keenly aware that any cooperative exploration of Mars — and the advances in space science it would make possible — would be vulnerable to the shifting political winds in Washington and Moscow. As the summiteers convened in the Soviet capital, U.S. scientists hoped that the President and the General Secretary would do more than give the idea diplomatic lip service.