PROBE'S SUCCESS OPENS POSSIBILITIES.

Byline: Tony Knight Daily News Staff Writer

The success of the Mars Pathfinder mission is proving that NASA can achieve its goal of building smaller, better and cheaper planetary probes that can do important and interesting science, space agency officials said.

A fleet of these new Discovery missions costing in the $150 million range in fiscal year 1992 dollars are expected to be launched in the next decade to continue the exploration of Mars and visit many other places in the solar system.

``It's clearly revolutionized the way we put together planetary missions here at JPL,'' said laboratory director Ed Stone. ``We needed to find a way to go back to Mars every time there was an orbital opportunity to do it, and that's every 26 months.''

A Discovery probe will launch this September to orbit and map the moon, another visited the asteroid Mathilde last week, and plans are being made to send another to orbit Jupiter's icebound moon Europa.

But it is Pathfinder, with its straight-in shot to Mars, its novel air bag landing, and its flawless return of sparkling color pictures within hours of touchdown that has erased doubts that such missions could be done, NASA officials said.

``The staff that worked on Pathfinder has been blazing a trail for three years,'' said NASA Administrator Daniel Goldin.

The lower budgets and smaller missions have allowed the National Aeronautics and Space Administration to plan a $1.8 billion Mars exploration program that includes 10 missions culminating with a mission in 2005 to return a load of Mars rocks to Earth.

By contrast, the twin Viking missions to Mars in the mid-1970s would have cost $3 billion in today's dollars.

``We have demonstrated quite clearly that we can build and launch planetary missions at a low cost,'' said Wesley T. Huntress Jr., NASA associate administrator for space science.

For its relatively small investment, NASA has been able to test out a low-cost delivery package to Mars, mobility on the Martian surface with the rover and the ability to conduct experiments extremely close to geological formations, Huntress said.

The Pathfinder mission was three years in development and planning, with a mere 38 months from NASA go-ahead to launch.

Total mission cost was $264 million, including $171 million for development of the lander and entry systems, $25 million for the rover, $55 million for the Delta II launch vehicle, and $14 million for mission operations.

The NASA of the 1970s and '80s had gotten in the habit of launching one monster space probe costing $1 billion or more at the rate of a little more than one per decade.

``We're doing it different this time,'' said Goldin. ``If we went the old way, we'd be waiting another seven years for the first ship out of port.''

Goldin attributed the success of Pathfinder to the young team of optimistic scientists and engineers at the Jet Propulsion Laboratory that designed and built Pathfinder. Most are in their mid-30s to early 40s.

``It's the result of these bright, young energetic people who don't know what the limits are,'' he said.

``I gave them the money, and I got out of their way,'' said Huntress.

It was the need to cut corners that led to the highly risky air-bag landing, said Rob Manning, the 39-year-old chief engineer who called the play-by-play on the morning of the landing.

``When we first proposed doing this, these old Viking guys told us we were crazy,'' Manning said.

Now even doubters like NASA's Jim Martin, the program manager for the 1976 Viking missions who was a chief critic of the air-bag landing, are seeing the possibilities.

``I'm now a convert,'' Martin said Saturday. ``In fact, I'm convinced that this is now the system we should use to land on any planet where we don't know what's already on the surface. This system is so robust. It could land on rocks, anything, even a river, because it would float.''