Posted by tourdemars to Life on Mars at September 17, 2003 12:00 PM

If life exists on Mars, how would we know? Scientists have been grappling with this deceptively simple question for years. Kenneth Nealson, the Wrigley Professor of Geobiology at the University of Southern California, is a leading authority on this issue, which he will address in a public lecture at the University of California, Santa Cruz, on Thursday, October 16.