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 ...

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 ...

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 ...

FLWO Visitor & Science CenterThe new Visitor & Science Center—showcasing astrophysics exhibits, live science demonstrations, and views of the surrounding Santa Rita Mountains and MMT Observatory— is ...

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 ...

Stars have a life cycle: they’re born, they pass through middle age, and they die. The birth of a star determines much of how it lives that life. For that reason, researchers study star-forming ...

Galaxies are home to most of the stars in the universe, and they form the beads of the cosmic jewelry that defines structure on the largest scales. But galaxies haven’t always been around, and they ...

How We Search. Exoplanets, or planets in solar systems other than our own, sometimes orbit directly between the Earth and their host star.When the planet orbits in front of its star, it blocks a small ...

The universe began 13.8 billion years ago, and in its early years, it looked completely different than it does now. For nearly 400,000 years, the entire cosmos was opaque, which means we have no ...

Stars are the source of almost all of the light our eyes see in the sky. Nuclear fusion is what makes a star what it is: the creation of new atomic nuclei within the star’s core. Many of stars’ ...

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 ...