"Physics for the 21st Century," a free, on-line course developed at the CfA about current research in physics is now available. It consists of eleven units that introduce cutting-edge top...

Cambridge, MA Our Sun can be a menace when it sends out powerful solar blasts of radiation towards the Earth. Astronomers keenly watch the Sun to learn more about what powers these sola...

About a dozen of the roughly 500 currently known extra-solar planets are super-Earths: planets with masses between about two and ten earth-masses. For larger extra-solar planets, an esti...

Cambridge, MA In December 2009, astronomers announced the discovery of a super-Earth known as GJ 1214b. At the time, they reported signs that the newfound world likely had a thick, gaseo...

Cambridge, MA The biggest galaxies in the universe are elliptical galaxies. The largest of these hold over one trillion stars according to astronomical census takers, compared to 400 bil...

New stars continue to appear in the night sky, as the gas and dust in giant interstellar clouds gradually coalesces under the influence of gravity until nuclear burning begins. Precisely...

Astronomers using NASA's Chandra X-ray Observatory have found evidence for the youngest black hole known in our cosmic neighborhood - a mere 30 years old -- that provides a unique opportu...

Gamma rays are the most energetic form of light, typically about one hundred billion times as energetic as optical light. Gamma rays are produced in four main ways: in extremely hot regi...

Cambridge, MA Dr. Brian Geoffrey Marsden passed away today at the age of 73 following a prolonged illness. He was a Senior Astronomer at the Smithsonian Astrophysical Observatory and Dir...

Cambridge, MA Sometimes when you're looking for one thing, you find something completely different and unexpected. In the scientific endeavor, such serendipity can lead to new discoverie...