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

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 ...

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 ...

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 ...

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 ...

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 ...

Black holes are some of the most fascinating and mind-bending objects in the cosmos. The very thing that characterizes a black hole also makes it hard to study: its intense gravity. All the mass in a ...

Most of the atoms in the universe are either hydrogen or helium, formed within the first few minutes after the Big Bang. The other elements are mostly made by nuclear fusion in stars, especially ...

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 ...

From its establishment in 1966 as the Smithsonian Mount Hopkins Observatory, FLWO has hosted a world-class suite of telescopes designed for a wide variety of purposes. The largest visible-light ...

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 ...

The Center for Astrophysics | Harvard & Smithsonian High Energy Astrophysics division focuses on X-ray astronomy and instrumentation involved in observations of high-energy sources. This research aims ...