Harvard University astronomers and Smithsonian Institution astronomers explore the cosmos together. The combination of the Harvard College Observatory (HCO) and the Smithsonian Astrophysical Observatory (SAO) is known as the Center for Astrophysics | Harvard & Smithsonian (CfA).

News Releases

March 5, 2021

Fabrication of the sixth of seven mirrors for the Giant Magellan Telescope has begun. The mirrors will allow astronomers to see further into the universe and with more detail than any optical telescope ever before.

February 15, 2021

It forever changed history when it crashed into Earth about 66 million years ago. The Chicxulub impactor, as it's known, left behind a crater off the coast of Mexico that spans 93 miles and runs 12 miles deep.

Latest Science Update

March 5, 2021

The binary star system Her X-1 consists of a 1.5 solar-mass neutron star – the super-dense, collapsed remnant of a massive star – in orbit around the 2.2 solar-mass star, HZ Herculis.

SI Specific Information

SI-specific information regarding the government shutdown may be found at alerts.si.edu. SAO staff are encouraged to review the website for updated information