Thursday May 17, 4pm<br>
Phillips Auditorium, Center for Astrophysics<br>
<br>
<br>
"Spectral Fingerprints of Earth-Like Exoplanets"<br>
Dr. Lisa Kaltenegger<br>
CfA<br>
<br>
Abstract: In a famous paper, Sagan analyzed a spectrum of the Earth
taken by the Galileo probe, searching for signatures of life. They
concluded that the large amount of O2 and the simultaneous presence of
CH4 traces are suggestive of biology. In this talk we discuss the
biomarkers at different wavelengths and focus on what makes a habitable
planet, using Earth as our example. We discuss surface, clouds and
biosignature evolution over geological time. We look at biomarkers on
planets around different stars, and set the measurements in context
with physical characteristics of a planet. The search for signs of life
implies that we need to gather as much information as possible in order
to understand how the observed atmosphere works physically and
chemically. How do we find them? How do we pick our targets? We live in
an exciting time when comparative planetology is a reality, and the
spectroscopic detection of life's signatures on worlds orbiting other
stars maybe achievable within a generation.<br>
<br>
<a href="http://www.cfa.harvard.edu/events/calendar/latest.html">http://www.cfa.harvard.edu/events/calendar/latest.html</a><br>
<br clear="all"><br>