The discovery of evidence that life may exist elsewhere in the universe raises that most profound of all human questions: Why does life exist at all? Is it simply that if enough cosmic elements slop together for enough eons, eventually a molecule will form somewhere, or many somewheres, that can replicate itself over and over until it evolves into a creature that can scratch its head? Or did an all-powerful God set in motion an unfathomable process in order to give warmth and meaning to a universe that would otherwise be cold and meaningless? The rock from Mars does not answer such questions. It does, however, make them feel all the more compelling.
Hurtling in from space some 16 million years ago, a giant asteroid slammed into the dusty surface of Mars and exploded with more power than a million hydrogen bombs, gouging a deep crater in the planet's crust and lofting huge quantities of rock and soil into the thin Martian atmosphere. While most of the debris fell back to the surface, some of the rocks, fired upward by the blast at high velocities, escaped the weak tug of Martian gravity and entered into orbits of their own around the sun.
After drifting through interplanetary space for millions of years, one of these Martian rocks ventured close to Earth 13,000 years ago--when Stone Age humans were beginning to develop agriculture--and plunged into the atmosphere, blazing a meteoric path across the sky. It crashed into a sheet of blue ice in Antarctica and lay undisturbed until scientists discovered it in 1984 in a field of jagged ice called the Allan Hills.
Last week that rock--dubbed ALH84001--landed on the front pages of newspapers around the world and seized the imagination of all mankind. At a televised press conference in Washington, a team of NASA and university researchers revealed that this well-traveled, 4.2-lb. stone--about the size of a large Idaho potato--had brought with it the first tangible evidence that we are not alone in the universe. Tucked deep within the rock are what appear to be the chemical and fossil remains of microscopic organisms that lived on Mars 3.6 billion years ago.
If that evidence stands up to the intense scientific scrutiny that is certain to follow, it will confirm for the first time that life is not unique to Earth. That confirmation, in turn, would have staggering philosophical and religious repercussions. It would undermine any remaining vestiges of geocentrism--the idea that man and his planet are the center of the universe--and strongly support the growing conviction that life, possibly even intelligent life, is commonplace throughout the cosmos.
To a world long fascinated by legends and fantasies about the Red Planet, the news had an electrifying effect, inspiring awe, disbelief, excitement--and, from not a few experts, skeptically raised eyebrows. The importance of the putative discovery was underscored by an immediate response from the White House. "Today Rock 84001 speaks to us across all those billions of years and millions of miles," proclaimed President Clinton as he set off for a three-day campaign swing through California. "It speaks of the possibility of life. If this discovery is confirmed, it will surely be one of the most stunning insights into our universe that science has ever uncovered."