Nasa Launches Mars Pathfinder

NASA launched a spacecraft to Mars early today carrying the first-ever interplanetary rover, a six-wheeled cart that will roam the frigid Martian surface in search of rocks.

The Mars Pathfinder began its 310 million-mile journey atop an unmanned rocket that lifted off at 1:58 a.m. It was the third try; launch attempts earlier in the week were stymied by bad weather and a computer failure.

Pathfinder is the second probe to be sent to Mars by NASA in the past month.

The Global Surveyor took off on Nov. 7, the first of 10 U.S. spacecraft to be sent to the Red Planet over the next decade in hopes of determining whether life ever existed there. A Mars spacecraft launched one week later by the Russians plummeted from orbit, adding to scientists’ anxiety over the flight of Pathfinder.

If all goes well, Pathfinder should beat the slower Global Surveyor to Mars by two months, landing on July 4, 1997.

It would be the first time in 21 years that a spacecraft has landed on Mars.

The $196 million Pathfinder, hailed by NASA as a new-wave bargain spacecraft, will aim for an ancient flood plain strewn with rocks. It will be a direct strike - no orbiting the planet first, a la the Apollo moon landings or the Viking probes.

A parachute will slow Pathfinder as it plunges through the Martian atmosphere. The parachute will drop away, and large air bags will inflate to cushion the impact.

Several hours later, the petals on the spacecraft are to unfold. Two ramps will pop out, and the 23-pound rover - named Sojourner - will amble down to examine nearby rocks and beam back information about their composition as well as color images.

NASA wanted to try this novel landing approach as practice for the all-important robotic mission planned sometime in the next decade to dig up Martian dirt and rocks - and return them to Earth.

Three-legged spacecraft like the twin Viking landers would never be able to land safely on such rocky terrain, the type of place NASA wants to ultimately scout for possible signs of life.

That strategy was reinforced in August when NASA scientists announced they had found supposed evidence of primitive life in a Mars meteorite. By coincidence, the rocks in Pathfinder’s targeted landing spot are about the same age as that prized 4-billion-year-old meteorite.

NASA had until the end of December to launch Pathfinder. After that, scientists would have had to wait until late 1998 or early 1999 when Earth and Mars are back in the necessary alignment. That’s when the next Mars probes will be launched.