Michael Shara

astronomer, American Museum of Natural History

Dr. Shara and his research group are conducting an exhaustive survey to inventory and "weigh" all 100,000 stars nearest to Earth. More than one billion stars are being examined in the search. The survey has already determined that many low luminosity stars remain undiscovered just a few light years away, and that a significant portion of the local "dark" matter is concentrated in stars 100 to 100,000 times fainter than the Sun. Dr. Shara uses the Hubble Space Telescope to survey the densest cores of globular clusters to retrieve and characterize the predicted collision products. These include some of the most exotic stars known to astrophysicists: "blue stragglers." By accurately weighing these stars, Shara and his collaborators have demonstrated that many are at least twice as massive as all other stars in a globular cluster. This strongly supports the hitherto theoretical collisional origin for blue stragglers.