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.