The Center for Astrophysics (CfA) provides world-class opportunities for academic training and career development in astrophysics. It is home to the Harvard University Department of Astronomy, which ...

Recipe for Stars and Planets Star formation happens in interstellar molecular clouds: opaque clumps of very cold gas and dust. The process starts when some of those clumps reach a critical mass, ...

Galaxy clusters are the largest objects in the universe that are held together by their own gravity. They contain hundreds or thousands of galaxies, lots of hot plasma, and a large amount of invisible ...

Our modern understanding of gravity comes from Albert Einstein’s theory of general relativity, which stands as one of the best-tested theories in science. General relativity predicted many phenomena ...

Our knowledge of the events and forces that shaped the early Universe is dependent on our ability to understand the most extreme conditions. On one hand, the Universe’s origin was incomprehensibly ...

Looking to our Future Stars follow different paths as they age, determined by their mass, with the most massive burning their fuel exponentially faster. Smaller stars, like our Sun, live long lives.

Center for Astrophysics | Harvard & Smithsonian scientists study galaxy formation and evolution in a variety ways: Looking for hidden structures and unusual stars that reveal the Milky Way’s history.

What We Know and What We Think While we can’t see dark matter, we know it’s there. And we can investigate some of dark matter’s properties using gravitational lensing. This technique measures the ...

Large galaxies like the Milky Way formed out of mergers with smaller galaxies and by stealing some of their stars. Astronomers discovered that as many as 25% of galaxies are currently merging with ...

For the first 380,000 years or so after the Big Bang, the entire universe was a hot soup of particles and photons, too dense for light to travel very far. However, as the cosmos expanded, it cooled ...

Supernovas are some of the brightest events in the universe, occasionally outshining entire galaxies at their peak. Many supernovas can be seen from billions of light-years away, and nearby supernovas ...

The Milky Way alone probably contains hundreds of billions of planets, based on the thousands of exoplanets we’ve already identified. These planets share a history and origin with their host stars, ...