Black holes are by far the "simplest" objects in the universe because they can be completely characterized by just three numbers: their mass, electric charge, and spin. Although they are...

In 1967, an X-ray sounding rocket discovered a fantastically bright source of X-ray emission coming from the direction of the constellation of Cygnus. Named Cyg X-3, it was soon identifi...

Cambridge, MA Astronomers have taken the closest look ever at the giant black hole in the center of the Milky Way. By combining telescopes in Hawaii, Arizona, and California, they detect...

Perhaps the most astonishing and revolutionary discovery in cosmology was Edwin Hubble's observation that galaxies are moving away from us. It provides the underpinning of the big bang p...

Cambridge, MA A new image from NASA's Spitzer Space Telescope tells a tale of life and death, and reveals a rich family history. The striking infrared picture shows a colorful cosmic clo...

New stars are continually forming in clouds of gas and dust in our galaxy. Astronomers at the CfA and elsewhere who watch these births have a very good (though not perfect) understanding...

There is now overwhelming evidence that the center of our Milky Way galaxy contains a giant black hole with a mass of about four million suns. The most convincing data come from the motio...

As modern telescopes peer more and more deeply into the universe, they are seeing older and older galaxies. The current record is a galaxy whose light has been traveling towards us for w...

Cambridge, MA

Solar flares, prominences, and so-called coronal mass ejections are three different manifestations of stored magnetic energy near the sun's surface being released in sudden eruptions. Th...