One of the world's most frequently posed questions may have been answered at an Aug. 7 press conference held at NASA headquarters in Washington, D.C. And so far, Cornell scientists believe the NASA-led research team that announced its findings to the world that day has provided excellent data to substantiate its claim that life once existed on Mars.

"The team did an extremely thorough and careful job, using highly sensitive analytical instruments," said Science (March 8, 1996) that when Mars and other inner planets are bombarded by asteroids and comets, materials from those planets are ejected into space. Those pieces ­ ranging from minuscule particles to grapefruitsized rocks or larger ­ travel along orbits continually perturbed by the planets themselves.

That is how ALH84001 landed on Earth's Antarctic shelf: Earth's gravity pulled it in.

The Cornell study showed that a few percent of the Martian ejecta will make it to the Earth.

Burns learned of the latest news Tuesday, Aug. 6, when a producer from ABC-TV's Nightline contacted him. The first report of the research on the Antarctic meteorite and the claims of Martian life forms had been scheduled to appear in today's edition of Science, but diligent science reporters apparently were tipped off by an article in another trade publication. The resulting deluge of unsolicited media attention forced NASA to hold the Aug. 7 press conference and lay out the findings.

Thomas Gold, Cornell emeritus professor of astronomy, was very pleased with the information scientists presented at the NASA press conference. In a July 1992 article, "The Deep, Hot Biosphere," published by the National Academy of Sciences, Gold had suggested the biogeological route the researchers eventually took to locate such biochemical signatures indicating Martian life.

"Personally, I think their case is very convincing," Gold said. "Bacteria reduce iron oxides to magnetite ­ not to iron ­ which is why the magnetite [found in the sample, indicating its Martian origin] accumulates. I'm very pleased with what I heard."

The association of magnetite with hydrocarbons seen in the meteorite strengthens the interpretation that microorganisms were responsible, Gold added.

His NAS paper contained the prediction that subsurface life would exist on Mars, as well as on other planetary objects.

Carl Sagan, the David Duncan Professor of Astronomy and Space Studies at Cornell and president of the Planetary Society, expressed delight at the scientific revelation in a commentary released Aug. 7 by the society. "This is the most provocative and evocative piece of evidence for life beyond Earth," he said.

"The apparent microfossil is dated to more than 3 billion years ago. This is a time when Mars was warmer and wetter than it is today, with lakes, rivers and possibly even oceans," Sagan said. "This is just the epoch in Martian history when you expect that life may have arisen."

Cornell social scientists also related NASA's findings to prevailing beliefs and doctrines in their fields. Scott MacDonald, a professor of philosophy and the Norma Kathryn Regan Chair of Christian Studies, noted that while some people interpret the Bible to mean that God's creation of life is unique to Earth, he knows of no established theological doctrines that explicitly confine life to this planet.

"The scriptures of the three great monotheistic religions ­ Christianity, Judaism and Islam ­ are utterly silent, as far as I know, regarding God's activity with respect to life elsewhere," MacDonald said. "One might suppose that the only place there is life is on Earth, or that Earth is the center of God's creation; but we haven't been given any reason in Revelations to think that there isn't life elsewhere."