CfA Colloquium Schedule Spring 2005
 14 April 2005

14 April 2005

Speaker: Eric Mamajek (Center for Astrophysics Clay Fellow)

Title: Clay Fellow Symposium
What Can Nearby, Young Stars Tell Us About Star and Planet Formation?

Abstract: 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:

  1. Mamajek, E, 2004, PhD Thesis, The University of Arizona
  2. Mamajek, E, Meyer, M., & Liebert, J. 2002, AJ, 124, 1670
  3. Mamajek, E, et al. 2004, ApJ, 612, 496
  4. Meyer, M., et al. 2004, ApJS, 154, 422
  5. FEPS website:


Section Photo