'Pathfinder' Blazes Cheap Trail to Mars

NASA probe will look for signs of life on planet

Exploring Earth's far-flung neighborhood on a shoestring budget gets its latest test Monday, as the United States prepares to launch Mars Pathfinder.

The mission to the Red Planet - the third international Mars launch in a month - aims to place a lander bearing a small, six-wheel rover on martian soil on July 4, 1997.

Targeted to land on an ancient flood plain, the package of cameras and sensors could help unlock secrets to the planet's past and whether it could have hosted life. It also is designed to prove that humans can extend their reach to the surface of another planet without draining taxpayers' wallets.

Mars Pathfinder's $196 million price tag is a fraction of the amount spent on sending a Viking orbiter and lander to Mars in the 1970s. "We've turned the old way of doing business upside down," says Wesley Huntress, associate administrator for space science at the National Aeronautics and Space Administration in Washington.

Set to launch at 2:09 a.m. Monday, the 1-ton Pathfinder payload uses parachutes, radar, small braking rockets, and air bags to soften its landing. Once down, the bud-like lander's three "petals" unfold. On one sits the rover, looking like a refugee from a 21st-century Sharper Image catalog.

Topped with a 2-by-1.5 foot array of solar cells, and with specially designed flashlight-size D cells included, the rover will allow researchers to determine the mineral makeup of martian soil. Traveling at nearly 12 feet per hour, the vehicle won't break land speed records. But its ability to find its way to a target once scientists on Earth tell it what to look at will allow researchers to study martian rocks in their original formations for the first time.

With the loss last week of Russia's Mars 96 mission, which consisted of an orbiter and probes to puncture the Martian surface, Mars Pathfinder represents the only hope of putting sensors on the planet for the next three years.

Ironically, the loss also illustrates why, in an era of tight budgets, NASA has shifted its approach to exploring the solar system from what administrator Daniel Goldin has called "Battlestar Galacticas" - billion-dollar, decade-long missions crammed with equipment, to smaller, more-focused projects that can be completed in under three years and for less than $150 million.

A bargain by historical standards, the $155 million Russian craft was designed to study Mars from orbit, as well as send probes into its soil. By contrast, Mars Global Surveyor, which lifted off last month, is to conduct studies of the planet from orbit, while Pathfinder will conduct studies on the surface. Losing one mission would be a disappointment, but the remaining mission would still keep Mars research moving forward.

PATHFINDER is the second mission in NASA's Discovery series, which embodies the "smaller, cheaper, faster" approach to solar-system exploration. The first, the Near Earth Asteroid Rendezvous mission, is set to waltz by the asteroid Matilda in June before taking up orbit around the asteroid Eros in 1999, says mission director Robert Farquhar.

The $122 million project to study these leftovers from the formation of the solar system already has set a space record of sorts, he adds. NEAR's position at more than 195 million miles from the sun "is the farthest a spacecraft has ever operated on solar cells."

Two more Discovery missions - one to orbit the moon next year and another, dubbed "Stardust," to gather and return samples of interstellar dust in 1999 - are in the pipeline.

Later this month, NASA will review proposals for the next round of missions, which range from space-based telescopes to look for planets around other stars, to missions to Mercury, Venus, and Mars. Mission designers must bring the projects in at at cost of less than $183 million.