The CfA is a collaboration of Harvard College Observatory (HCO) and Smithsonian Astrophysical Observatory (SAO) and home to Harvard's Department of Astronomy.

News Releases

October 24, 2014

The moon passed between the Earth and the sun on Thursday, Oct. 23. While avid stargazers in North America looked up to watch the spectacle, the best vantage point was several hundred miles above the North Pole.

October 16, 2014

Why is the Sun's million-degree corona, or outermost atmosphere, so much hotter than the Sun's surface? This question has baffled astronomers for decades.

Latest Science Update

October 31, 2014

Water, the key ingredient for life, is not only abundant on Earth, it is also ubiquitous across the solar system. Either as ice or sometimes as liquid, water has been spotted in comets, the icy moons of the giant planets, and even in the shadowed basins of Mercury.

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