An unexpected monster black hole was found hiding inside one of the Milky Way's tiniest neighbors, rewriting what scientists thought they knew about how small galaxies hold themselves together.

Most of these astrophysical monsters are stars with various behavioral issues, such as explosive supernovae or ridiculously powerful (and tempestuous) magnetars. In a recent The Universe column, I wrote about particularly nasty cosmic nightmares called active galaxies.

Astronomers suspect the giant black hole at the heart of the Milky Way may have collided with another black hole in just the past 10 million years. At the core of the galaxy, about 26,000 light-years away in space, is Sagittarius A*, a supermassive black ...

At the heart of the Milky Way, just 27,000 light-years from Earth, there is a supermassive black hole with a mass of more than 4 million suns. Nearly all galaxies contain a supermassive black hole, and many of them are much more massive.

Researchers are using black hole “shadow” images to test whether Einstein’s relativity remains unshakable. With next-generation telescopes, they hope to spot telltale signs of alternative physics lurking at the edge of the abyss.

The Big Bang theory has dominated our understanding of the universe’s origin for almost 100 years. It describes a moment when all of space, time, and energy were born from a single infinitely dense point.