For roughly two billion years of Earth’s early history, the atmosphere contained no oxygen, the essential ingredient required for complex life. Oxygen began building up in the atmosphere during the

Astronomers have performed the deepest radio observations ever of Omega Centauri, searching for signs of an intermediate mass black hole thought to lurk at its center. Despite 170 hours of

Researchers have discovered that a close encounter with a rogue planet or brown dwarf during the Sun’s early years could have triggered the reshuffling of our Solar System’s giant planets.

Astronomers at the University of Tokyo have used gravitational lensing to measure how fast the universe is expanding, adding weight to one of cosmology’s most intriguing mysteries. Their technique exploits

A new study, analyzing over 1,600 galaxies observed with Chandra over two decades, suggests that smaller galaxies do not contain supermassive black holes nearly as often as larger galaxies do.

In the early 20th century, after years of effort, Albert Einstein developed his general theory of relativity. This was a massive improvement in our understanding of gravity, giving us a