Ancient meteorite may point to life on Mars

'Biggest discovery in the history of science'

August 7, 1996
Web posted at: 1:15 p.m. EDT

WASHINGTON (CNN) -- NASA announced Wednesday that a primitive form of microscopic life may have existed on Mars about 4 billion years ago.

The announcement was made in Washington at a news conference to discuss the findings, made by researchers from NASA and various universities.

Before the news conference, a source close to the agency told CNN, "I think it's arguably the biggest discovery in the history of science."

NASA Administrator Daniel Goldin had said Tuesday the research is based on a sophisticated examination of an ancient Martian meteorite, labeled Allan Hills or ALH 84001, that landed on Earth about 13,000 years ago. The meteorite was found in Antarctica in 1984.

Researchers examining the rock from space say it contains organic compounds that are unmistakable evidence that life once existed on the red planet.

"I want everybody to know that we are not talking about 'little green men,' " Goldin said. "These are extremely small, single-cell structures that somewhat resemble bacteria on Earth. There is no evidence or suggestion that any higher life form ever existed on Mars."

The scientists will publish their findings in the August 16 issue of Science magazine. NASA's research was sponsored by the Johnson Space Center in Texas.

Scientists hail the possibilities

"It means a lot," astronomer Richard Berendzen of American University told CNN.

"It means a long-lost discovery, a thing that astronomers have been looking for for decades." (341K AIFF or WAV sound)

Astronomer and author Carl Sagan, who has studied the possibility of extraterrestrial life and investigated the origins of life on Earth, called the discovery "glorious."

"The chance of independently arriving at the same kind of life on two independent planets is very small. That is one of the great excitements -- to see what two different planets, how their evolutionary history proceeds," he said. (265K AIFF or WAV sound)

Collision brought meteorite to Earth

Scientists believe the meteorite was blasted away from Mars by the impact of asteroids, and landed on Earth. It is the oldest of the 12 Martian meteorites discovered on Earth.

Scientists who have studied the meteorite say it bears chemical markers that may be evidence of biological activity. However, other scientists said the markers are far from conclusive.

A source at NASA told CNN the meteorite shows a bacterial form which he described as "looking like little maggots."

Martian life forms may still exist

NASA scientists doubt that anything is currently alive on Mars, but they're not dismissing the idea. Mars today is in an Ice Age.

If the meteorite found in Antarctica is billions of years old, it dates from the earliest days of Mars, at the time the planet formed.

Scientists say it is probable that Mars was very hot in the beginning. As it cooled, it is possible the very basic elements of life formed there.

There's evidence of water and volcanoes on Mars -- and that combination means at some point there probably were organisms living deep underground in hydrothermal vents, similar to the geysers at Yellowstone National Park, scientists say.

"So if life can exist under the ground on Earth, maybe it can exist under the ground on Mars, too," said Paul Davies of the University of Adelaide in Australia.

Davies said life forms that began on Mars billions of years ago may have taken cover deep below the Martian surface, and might even still be living there. The life forms could have gone underground as permafrost or may be contained in the planet's ice caps.

"I think there's a reasonable possibility that we will find something on the next NASA mission to Mars," Jack Farmer of NASA said.

Pathfinder, the next NASA mission to Mars, is scheduled for launch late this year but won't be able to dig deep enough to search for current or former life below the Martian surface. NASA says such a probe is at least 10 years away.

Correspondent Ann Kellan, reporter Jim Slade and The Associated Press contributed to this report.

Related stories:

• Your comments on Mars: Life Signs?

Related sites:

• Today@NASA - Current NASA press information
• NASA Home page
• Science On-Line - the latest issue of the journal
• SNC Meteorites
• Johnson Space Center
• Science Space Page

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