Looking for hidden structures and unusual stars that reveal the Milky Way’s history. Since our galaxy grew by merging with and eating other galaxies, traces of that violent past are visible in the ...

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 ...

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 ...

Everything you’ve ever seen or experienced on Earth was once a nebulous collection of floating gas and dust. Science is starting to understand how those particles came to take the forms you recognize ...

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 ...

Modern astronomy requires the best telescopes, detectors, spacecraft, and other equipment. The scientists, engineers, and staff of the Center for Astrophysics | Harvard & Smithsonian participate in ...

The Fred Lawrence Whipple Observatory (FLWO), part of the Center for Astrophysics | Harvard & Smithsonian, is a major observatory based in Mount Hopkins, Arizona. Alongside its status as an active ...

The observable universe is home to more than a hundred billion galaxies of many shapes and sizes. The most distant galaxies are relics of an earlier era, so observing them is a glimpse at history.

Everywhere we point telescopes in the sky, we see galaxies, going back to the earliest moments in history where galaxies could even exist. These galaxies fall into a pattern: the large-scale structure ...

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 ...

April (Meteor) Showers and See a City of Stars! Enjoy observing planets in the morning and evening sky, look for Lyrid meteors, and hunt for the "faint fuzzy" wonder that is the distant and ancient ...

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 ...