Smithsonian Astrophysical Observatory

Science Updates


Astronomers studying how star formation evolved over cosmic time have discovered that quiescent galaxies (galaxies that are currently not making many new stars) frequently have active galactic nuclei. These AGN accrete material onto hot circumnuclear disks, and the resultant energy is released in bursts of radiation, or as jets of particles moving at close to the speed of light.


Massive galaxies in the local universe, in order to be large today, probably began forming their stars in the early universe. Astronomers do indeed see significantly enhanced star-formation activity in distant galaxies and find that the peak star formation rate occurred when the universe was only about two billion years old.

The Smithsonian Astrophysical Observatory (SAO) is a "research institute" of the Smithsonian Institution. It is joined with the Harvard College Observatory (HCO) to form the Harvard-Smithsonian Center for Astrophysics (CfA). Because these research activities share Harvard and Smithsonian staff and resources, the links at this website will take you to information posted on the "CfA" pages.