Smithsonian Astrophysical Observatory

Science Updates


The ionization of the neutral gas in an interstellar molecular cloud plays a key role in the cloud's evolution, helping to regulate the heating and cooling processes, the chemistry and molecule formation, and coupling the gas to magnetic fields.


Ultraluminous infrared galaxies (ULIRGs), powered by starburst activity and often with supermassive black holes accreting material at their nuclei, contain large reservoirs of molecular gas. This is to be expected: Molecular gas is the raw material for new stars and moreover the presence of the infrared luminous warm dust implies an abundance of molecular gas.

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.