Space: Program for the Planets

With only 2% of NASA's heavily slashed budget at its disposal, the once-ambitious U.S. planetary-exploration program is in danger of expiring before it gets to the launching pad. Anxious to keep from "abandoning the planets to Russia," 23 top space scientists last week recommended a program designed both to appeal to congressional penny pinchers and to reach the planets. In the next seven years, the new plans could take unmanned U.S. spacecraft to Jupiter and beyond.

In a report by the Space Science Board of the National Academy of Science, the experts mince no words about two costly sacred cows: manned interplanetary flight and redundancy of experiments. Funds now earmarked for manned programs, they insist, should be diverted to unmanned instrumented flights that are "capable of answering the major scientific questions that we can now pose about the planets." For flights beyond the moon, the report sees no current need for "the unique abilities of man," neither his on-the-spot reasoning nor his capability for unprogrammed reaction.

Because planetary exploration "is no longer a primitive and risky art," the scientists say, the accepted practice of launching two spacecraft to accomplish the same mission, and the construction of a third duplicate craft as a "backup," in the event of twin failure, is largely unnecessary. They recommend, however, that NASA proceed with the only planetary flight now funded and scheduled—a photographic flyby of Mars in 1969 by two Mariner spacecraft. The flights would not be redundant, the report notes, because each Mariner is scheduled to photograph a different area of the Martian surface.

Economy Preferred. Despite the tight budget squeeze, the space panel stresses the importance of exploratory space flights to Mars and Venus each time the earth's neighbors are in a favorable position—about five or six times a decade. But instead of using complex and expensive Mariner or Voyager spacecraft for these flights, the scientists recommended the older and more economical Pioneer-type craft first launched in 1958. They are smaller than the Mariners and spin at 60 r.p.m., but can be crammed full of sophisticated new instruments. Placed into orbit around the planets, the little craft could return detailed scientific data and even take pictures with a transistorized, 10-Ib. TV camera. Pioneers could also be flown past Jupiter in 1972 and 1973.

Because of the age-old curiosity about life on Mars, the report also gives top priority to a Mariner orbital flight in 1971 and a Mariner-type craft that could orbit and land on the red planet by 1973. Mariner's large payload would enable it to carry instruments that might well detect life on Mars, if it exists.

Grand Tour in Space. Beyond this "minimal" program, the scientists say, there are other planetary opportunities that the U.S. should grasp. In 1973 and 1975, for example, the planets will be positioned so that a Mariner flying past Venus will be whipped by Venusian gravity into a trajectory that will carry it close to Mercury, affording man his first glimpse of the sun's nearest neighbor. And in 1977 and 1978, planetary positions will enable a spacecraft flying by Jupiter to take a gravity-boosted "grand tour" that will also take it on past Saturn, Uranus and Neptune.