Astronomers have made a surprising discovery that challenges current theories of galaxy formation. A colossal disk-shaped galaxy, nicknamed the "Big Wheel," has been found just two billion years after ...

This NASA/ESA Hubble Space Telescope image features the picturesque spiral galaxy NGC 4941, which lies about 67 million light ...

you’re seeing what a team of astronomers spied last year—a rare formation created by the grazing collision of two spiral galaxies. Galactic sideswipes aren’t unusual, says lead researcher ...