NASA May Scrub New Shuttle Rocket : Space: The agency’s proposed $15-billion budget plan would also scrap a comet probe and shut down a Venus spacecraft.

A controversial $3-billion program to build advanced solid rockets for the space shuttle has been omitted from the 1993 federal budget, along with ambitious plans by the Jet Propulsion Laboratory in Pasadena to send a robotic spacecraft to a comet and an asteroid.

Those projects were the big losers in the $15-billion budget for the National Aeronautics and Space Administration. The biggest winner was the $30-billion to $40-billion Space Station Freedom, which received full funding of $2.25 billion for the coming year.

In addition, JPL’s Magellan spacecraft, which just resumed mapping the surface of Venus after engineers resolved a critical communications problem, will end its work next year, disappointing scientists who had hoped that the probe could keep studying Venus for several more years.

The move to terminate JPL’s Comet Rendezvous/Asteroid Flyby mission, which would have sent a $700-million spacecraft to fly alongside a comet, was a bitter blow to the Pasadena facility.

“It’s always a disappointment” to see a major program killed, said JPL Director Edward C. Stone Jr. He said that the decision was forced by the constraints on the proposed NASA budget, which kept just barely ahead of inflation.

“That’s just not adequate to maintain the kind of space program this country should have,” Stone said.

Budget constraints also were cited by NASA Administrator Richard H. Truly as the reason for canceling the advanced solid-rocket program, which has been under constant criticism from space policy experts who saw it as a classic case of pork-barrel politics.

Work is already under way in northern Mississippi on the huge plant that was to build the new rockets. It is located in the district of Rep. Jamie L. Whitten (D-Miss.), chairman of the powerful House Appropriations Committee.

Critics have argued that the only reason for building the plant was to appease Whitten, and while Truly defended the program, he also said Wednesday that to continue it during the present budget climate “would do unacceptable damage to the rest of NASA’s program.”

He also said that the present solid rockets, which were redesigned after the space shuttle Challenger exploded six years ago, have proved adequate.

The budget submitted for NASA deleted $469 million that had been pegged for the advanced rocket program next year. Congress can either provide additional funding to continue the project or simply require NASA to go ahead with it and take the funds from other programs.

The latter course, Truly said, would decimate much of the space program.