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.

About 13.8 billion years ago, the Big Bang gave rise to everything, everywhere, and everywhen—the entire known Universe. What caused the Big Bang? What happened that first moment at the beginning of ...

Center for Astrophysics Harvard & Smithsonian How can we expand the limits of human knowledge further into the unknown? The Center for Astrophysics is a collaboration between the Smithsonian ...

All the atoms and light in the universe together make up less than five percent of the total contents of the cosmos. The rest is composed of dark matter and dark energy, which are invisible but ...

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 ...

The Milky Way is our galactic home, part of the story of how we came to be. Astronomers have learned that it’s a large spiral galaxy, similar to many others, but also different in ways that reflect ...

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 ...

Center for Astrophysics | Harvard & Smithsonian scientists study many different aspects of galaxy clusters: Mapping the structure of galaxy clusters using the hot plasma that fills the space between ...

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 ...

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 ...

Matter and energy are the two basic components of the entire Universe. An enormous challenge for scientists is that most of the matter in the Universe is invisible and the source of most of the energy ...

Center for Astrophysics | Harvard & Smithsonian scientists study planetary nebulas in several different ways: Identifying the atoms and molecules within planetary nebulas, mostly through the infrared ...