14 April 2005
14 April 2005
Speaker: Eric Mamajek (Center for Astrophysics Clay Fellow)
Clay Fellow Symposium
What Can Nearby, Young Stars Tell Us About Star and Planet Formation?
The nearest, youngest stars to the Sun have much to teach us
about star and planet formation. I will present recent results
from my PhD thesis and on-going research in support of the
"Formation and Evolution of Planetary Systems" (FEPS) Spitzer
Legacy Science program. It appears that the duration of
star-formation in the giant molecular clouds that form OB
association subgroups is short (<5 million years), and that
circumstellar accretion disks around ~99% of solar-type stars
disappear within their first ~13 million years of life. We used
the MIRAC-3 mid-infrared camera on the 6.5-m Baade telescope to
place strong constraints on the amount of warm dust orbiting
~30 million year-old stars (similar in age to when the
Earth-Moon system formed in our own solar system).
I will discuss a technique for estimating distances to nearby
young stars using proper motions, as well as recent efforts to
estimate ages for the 350 solar-type stars in the FEPS program.
Improved age estimates are critical to helping meet the FEPS
goal of understanding the evolution of dust and gas around
solar-type stars between ages 3 million and 3 billion years.
Video of the Presentation
(Talks can be viewed with RealPlayer. Free download
is available from
References for students:
Mamajek, E, 2004, PhD Thesis, The University of Arizona
Mamajek, E, Meyer, M., & Liebert, J. 2002, AJ, 124, 1670
Mamajek, E, et al. 2004, ApJ, 612, 496
Meyer, M., et al. 2004, ApJS, 154, 422
FEPS website: http://feps.as.arizona.edu/