ROANOKE TIMES 
                      Copyright (c) 1996, Roanoke Times

DATE: Thursday, August 8, 1996               TAG: 9608080046
SECTION: NATIONAL/INTERNATIONAL   PAGE: A-1  EDITION: METRO 
SOURCE: Los Angeles Times
NOTE: Lede 

LIFE ON MARS? 'WOW!' NASA EXULTS, CHALLENGES SCIENTISTS

Declaring Wednesday ``the day we opened the door'' to other worlds, NASA chief Dan Goldin promised to do whatever is necessary to confirm whether the microscopic worm-like structures found on a meteorite from Mars are really signs of life beyond Earth.

That might include, he said, more missions to Antarctica to pick up stray pieces of the red planet, sending astronauts to dig into Mars, or developing better microscopes to probe the samples already on hand.

Goldin challenged scientists around the globe to study the evidence to disprove the findings.

The overwhelming international reaction, he said, could be summed up in a single word: ``Wow! ... We're now on the doorstep to the heavens,'' he said, sighing: ``What a time to be alive!''

President Clinton joined in the accolades, saying, ``If this discovery is confirmed it will surely be one of the most stunning insights into our universe that science has ever uncovered. Its implications are as far-reaching and awe-inspiring as can be imagined.''

Scientists who analyzed the cosmic rock presented their findings at NASA headquarters Wednesday to an international audience.

Meticulously reconstructing their trail of evidence, they stressed that results would have to be confirmed by further study.

``We think they are microfossils from Mars,'' said Stanford University's Richard Zare. ``But this is an interpretation. It could be a dried up mud crack.''

UCLA's William Schopf, an authority on evolution who has found some of the oldest fossil bacteria on Earth, gave several reasons to be skeptical. To be sure they were alive, he said, ``We've got to look inside these things.'' That will be no easy task because the structures range from 1/1,000th to 1/100th the diameter of a human hair.

Johnson Space Center's David McKay, principal author on the research, stressed several times that the findings were tentative. The researchers believe the structures have a biological origin because it's the simplest idea that fits all the evidence.

As a ``smoking gun'' to clinch the diagnosis of fossil life, Schopf said he would like to see a cell wall separating the structure's inside from its outside, and population of structures that were clearly different from their environment. Most of all, he said, he would like to see signs of cell division - in other words, reproduction.

Next, the researchers will analyze the rock in much greater detail, in particular, to look for what McKay called ``the inside machinery of the cell,'' or evidence of walls.

To find present life on Mars would require digging deep inside the planet to find remnants of still watery worlds protected from the ultraviolet radiation of the sun. The only way to find out if such a world really exists, said McKay, ``is to go there.''

And if such a mission requires sending astronauts to Mars, said Goldin, ``We'll do it.''

LENGTH: Medium:   66 lines
ILLUSTRATION: PHOTO:  AP. This potato-sized rock, believed to be Martian, was 
          the center of attention for cosmic ponderers all over Earth 
          Wednesday. Scientists will give it even more scrutiny, scouring it 
          for biomolecules such as amino acids. color. Graphic:Chart. color.