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 Harvard-Smithsonian Center for Astrophysics (CfA).

News Releases

April 30, 2018

You don't get to swim in the sun's atmosphere unless you can prove you belong there. And the Parker Solar Probe's Faraday cup, a key sensor aboard the $1.5 billion NASA mission launching this summer, earned its stripes last week by enduring testing in a homemade contraption designed to simulate the sun.

April 3, 2018

This winter has brought many intense and powerful storms, with cold fronts sweeping across much of the United States. On a much grander scale, astronomers have discovered enormous "weather systems" that are millions of light years in extent and older than the Solar System.

Latest Science Update

May 25, 2018

The center of our Milky Way galaxy is about twenty-five thousand light years from Earth, in the direction of the constellation Sagittarius. At the core of the galaxy is a supermassive black hole with about four million solar-masses of material and around it, within a volume just a few light-years in radius, orbit hundreds of massive stars and probably hundreds of thousands of smaller, harder to detect stars.

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