Seeking Signs of Life On Mars

Thursday, Feb. 10, 2011 — 8:00 p.m.
Science Center 199

Diverse organic molecules containing carbon, hydrogen, oxygen, nitrogen and sulfur are common in meteorites, comets, and interplanetary dust particles. These pre-biotic ingredients rain down on planetary surfaces, providing molecular building blocks for a potential origin of life anywhere where liquid water is present. Ancient Mars appears to be particularly well suited for the transition from pre-biotic to biological activity given increasing evidence of an active water cycle and diverse aquatic environments around 4 billion years ago. The scientific and engineering community has proposed a 2018 rover mission to drill and cache samples as the first step in a campaign to bring Martian rocks and soils back to Earth for study. In preparation for seeking evidence of past or present Martian life, innovative new life-detection instruments are being tested in harsh Arctic and Antarctic environments.

Lisa M. Pratt is Provost's Professor of Geological Sciences at Indiana University. As part of her research into life-sustaining energy for microbes in the deep subsurface of Earth, she has collected samples of water, rock, and natural gas in active gold mines at depths up to 2.5 miles below the surface in South Africa and in the Canadian Arctic. Her research on radiolysis of water as a source of energy for microbial metabolism has been highlighted worldwide. She recently chaired a NASA science advisory group that proposed a 2018 rover (Mars Astrobiology Explorer and Cacher), equipped to drill and encapsulate rock cores as the first step in a sample return campaign.