How did a Cepheid variable star help Edwin Hubble prove the Andromeda Nebula was a galaxy? Roger BradySan Quentin, California ...

Astrophotographer Greg Meyer has captured a colorful view of the famous Trifid and Lagoon nebulas illuminated from within by radiation cast out by generations of energetic young stars.

The Andromeda Galaxy, located 2.5 million light years away, has fascinated observers for centuries. Once believed to be part of the Milky Way, everything changed in 1923 when Edwin Hubble identified ...

Credit: A Rainbow Mosaic of the Rosette and the Christmas Tree Nebulae © Shaoyu Zhang Behold! The 2025 ZWO Astronomy ...

Clearly, the Andromeda Nebula was a system of stars quite separate from the Milky Way, and in many ways comparable to it. From this simple observation, soon repeated for other starry nebulae, it ...

A hundred years ago, astronomer Edwin Hubble revealed a universe of galaxies that existed beyond ours. His influence in astronomy continues to this day.

For years, astronomers have predicted a dramatic fate for our galaxy: a head-on collision with Andromeda, our nearest large galactic neighbor. This merger—expected in about 5 billion years—has ...

Previous research into the impending merger assumed that Andromeda’s transverse motion was small, making the potential for a Milky Way merger much higher. But the newest findings suggest otherwise.

Andromeda XXXV is only about 20,000 times more massive than our Sun—very small, even for a satellite galaxy. For comparison, the Milky Way’s mass is about 1.5 trillion solar masses, and the ...

This deep view of the Orion Constellation glows in reddish hues thanks to a filtered view of hydrogen alpha emission, a type ...