A Tale of Two Telescopes or Dancing with the Stars
Saturday, February 3, 2007
1-2 P.M., 2.302 ACES
Dr. Fritz Benedict
Senior Research Scientist
The University of Texas at Austin
Astronomers have discovered nearly two hundred
extrasolar planets orbiting other stars.
How? By measuring the ever so slight velocity change
as the star and planet dance around their common center
of mass. But what kind of planets are they? Jupiters?
Neptunes? An extrasolar planet could even
turn out to be
a low mass star! In this tale of two telescopes I show
how we first discover these companions by
the *biggest* optical telescope, the Hobby-Eberly
Telescope. Fortunately, the stellar dance moves side to
side as well as to and fro. To reveal the mass of the
planet, we next measure the size of that tiny side to
side wiggle with the *highest* optical
Space Telescope. How tiny a wiggle? The width of a
quarter 800 miles away.
None of the planets we have weighed are
or what I call prime real estate. Will I ever find any?
That requires an increasing NASA budget, a third
telescope, and healthy, alert old age.
The Great Lectures in Astronomy series features distinguished speakers presenting a topic in modern astronomy for interested non-astronomers. The lectures are sponsored by the McDonald Observatory and Department of Astronomy Board of Visitors.