In 1920, astronomers Harlow Shapley and Heber Curtis held a Great Debate. Shapley argued that the spiral nebulae were small and in the Milky Way, while Curtis took a more radical position that they ...

Predictions are uncertain, but the solar system may be pushed farther from the galactic core or even ejected entirely from the new galaxy.

Astronomers spent a decade compiling this special image with the Hubble Space Telescope and then stitched together 600 photos to showcase over 200 million stars.

Centaurus A: NGC 5128 is a galaxy in constellation Centaurus, discovered in 1826 by Scottish astronomer James Dunlop. Messier ...

A bouquet of thousands of stars in bloom has arrived. This composite image contains the deepest X-ray image ever made of the ...

This image was created by combining data from three major observatories: NASA’s Chandra X-ray Observatory, the Hubble Space ...

Astronomers trace the striking pattern to an encounter between a big galaxy and a much smaller one some 50 million years ago.

October belongs to Pegasus and the water constellations, which float through the southern sky after nightfall. Reigning supreme high in the south are the Great Square of Pegasus and, stretching from ...