Research in the Department of Astrophysics includes:

• Star formation and feedback
  
• Galaxy formation
• Stellar populations and evolution
• Instrument development
  

Research in Astrophysics at the Museum focuses on the formation and evolution of stars and star clusters and on the effects of their radiation and supernova explosions on interstellar and intergalactic gas. The program includes both observations from major ground and space-based observatories including the Hubble Space Telescope, and computational modeling using facilities including the Museum's Parallel Computing Facility and special-purpose GRAPE machines for computing gravitational forces at speeds of several teraflops.

The department also hosts the Lyot Project. The Lyot Project involves the construction of the world's most precise stellar coronagraph which will provide unprecedented sensitivity to extremely faint object orbiting nearby stars. It works by the same principle as a solar coronagraph, that blocks out the Sun's light to view the corona, and will be mounted on a telescope in Hawaii with an excellent adaptive optics system--a rubber mirror to remove the blurring caused by the Earth's atmosphere.

The question of how star formation proceeds over the history of the Universe has been the focus of the work of Associate Curator Mordecai-Mark Mac Low. The clouds of interstellar gas from which stars form are not quiescent, but rather in a state of hypersonic turbulence. Mac Low and his colleagues find that these extreme turbulent motions appear to determine the speed with which the gas collapses into stars, and perhaps also the distribution of stellar masses.

Michael Shara curated the Einstein exhibition, shown at AMNH from November 15, 2002 to July 27, 2003. The exhibition hosted over 100,000 visitors during its first 4 months and garnered significant positive attention from the media and museum supporters. Shara organized and co-hosted a one day symposium (May 19, 2003) on the Einstein Papers Project. Speakers include most of the leading historians of science working through the personal and scientific papers of Albert Einstein. The Department of Astrophysics also helped organize a public forum on the Einstein Papers, and a second entitled "Science and Society: Academic Freedom vs. National Security."

AMNH postdoctoral fellow Sebastien Lepine and Shara continue cataloguing the 1,000,000 stars closest to the Sun. Some of the oldest, faintest and most metal-poor stars known have already been detected. Working with AMNH graduate student Akimi Fujita, Mac Low has also investigated how the ionizing radiation and supernova explosions from the first galaxies in the Universe escape into the surrounding intergalactic medium, perhaps preventing the formation of nearby galaxies.

Shara also detected several hundred erupting novae in the giant elliptical galaxy M87 in the Virgo galaxy cluster. The presence of extremely luminous novae in this ancient galaxy is quite unexpected, and he and AMNH Hubble postdoctoral fellow Jarrod Hurley are carrying out extensive stellar poulation simulations to determine the progenitors of these novae.

Shara and colleagues will carry out a narrowband imaging survey of much of the Milky Way Galaxy in 2004 and 2005, to locate the expected 2,000 pre-supernova Wolf Rayet stars scattered across our Galaxy. Detailed planning of the optimal observing strategy, including simulations of various imaging filters, is underway.