PASADENA, Calif. -- NASA's little Martian rover crept about the surface of the Red Planet yesterday, prospecting for answers to a burning scientific question: Was early Mars like early Earth: warm, wet and hospitable to life?
The first data relayed back from Pathfinder, the rover's mother ship, revealed nothing to contradict that theory -- in fact, the data helped support it.
Striking images from Pathfinder's color camera showed a tantalizing grab-bag of multicolored rocks, soils, hills and craters, some with remarkably Earth-like features that will keep researchers busy for years to come.
"The rover is on the surface of Mars the scientists are in heaven," said Richard Cook, the Mars mission manager at NASA's Jet Propulsion Laboratory (JPL).
The Pathfinder team gave puckish nicknames to a number of the objects captured in their initial scan of the Martian landscape.
The rover's first target for close study, a nearby dark-gray rock covered with little barnacle-like lumps, was tagged "Barnacle Bill." Just beyond lies "Yogi," a large, black boulder chosen as the next to be inspected.
Farther off are a whitish stone named "Casper," a flat rock dubbed "Flattop," a long, mysterious object labeled the "Couch," and in the distance, two hills known as "Twin Peaks."
The names may seem "silly and childish," said Henry Moore, a retired geologist on the Mars rover team. "But we work very hard, and it helps us keep our sense of humor."
Scientists are especially intrigued by the Twin Peaks, which appear to be several hundred yards high and a mile away.
One cone-shaped peak is marked by a whitish stripe, resembling a ski run, and mounds of sloughed-off dirt around its base. Ronald Greeley, a University of Arizona geologist on the Mars team, said the formation is "very reminiscent of what we see in Arizona."
The other hill shows four or five horizontal bands of rocks, like those in the Grand Canyon. Greeley said the bands could be layers of sediment deposited by floods or possibly the shorelines of dried lakes.
"They are all indicative of water in an ancient flood plain," he said. "We are seeing evidence of multiple episodes of flooding, not just one catastrophic flood."
Smaller objects picked up by Pathfinder's camera provided further confirmation that Mars had a watery past.
A cluster of rocks tilted in the same direction look like similar stones found in rivers on Earth. And many of the boulders are smooth and rounded, a sign of erosion by fast-flowing streams.
Very similar rocks are washed down from glacial lakes in Washington state and Iceland, Greeley said.
In contrast, Barnacle Bill and other rocks have rough, sharp edges. Scientists believe they were gouged out of the planet's crust by the impact of meteors. This would be the same process that probably gave birth to the Martian meteorite that landed in Antarctica 11 million years ago and that some scientists believe contains evidence of fossilized life.
Dan Britt, a Mars team geologist, said rocks like Barnacle Bill are scattered around a mile-wide meteor crater in Arizona.
The rover's first scientific task yesterday was to put its nose -- an instrument called an X-ray spectrometer -- to the ground to sniff out its chemical composition.
Then it was to turn 70 degrees and ease up to Barnacle Bill, where it was to spend the next 10 hours analyzing its chemistry.
Matthew Golombek, Pathfinder's chief scientist, said it will take a long time to analyze the data streaming in from Mars at the speed of light.
Already, he said, there is ample evidence to confirm that Mars was once warm enough to have had liquid water, an essential precondition for life.
Mars still has an enormous amount of water, he said, enough to cover the planet with an ocean a half-mile deep, but it is frozen in the polar ice caps or locked in a thick layer of permafrost that scientists believe lies beneath the barren surface.
"Mars is a water-rich planet," Golombek said. "It may be more water-rich than Earth."
He speculated that great floods occurred 1 billion to 3 billion years ago, when giant meteors or earthquakes broke the Martian crust and the waters spewed out under high pressure, carving channels like the one where Pathfinder sits.
While they eagerly await more data, JPL scientists can hardly contain their enthusiasm.
"Everything is going absolutely perfectly," said Golombek. "We're more excited than you could possibly believe."
Pub Date: 7/07/97