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 ...

If scientists confirm an anisotropic expansion, it would challenge the assumption that the universe has no preferred directions.

Using the Hubble Space Telescope (HST), astronomers have observed a supermassive galactic open cluster designated Westerlund ...

Hubble’s high-resolution imagery allowed researchers to hone in on more of the Bullseye galaxy’s rings — and helped confirm ...

For decades, scientists have worked to map the universe’s large-scale structure, testing cosmological models and ...