The Helix Nebula is an example of a planetary nebula. Though it looks like a bubble or eye from Earth’s point of view, the Helix is actually a trillion-mile-long tunnel of glowing gases. In its center ...
When you buy through links on our articles, Future and its syndication partners may earn a commission. This Hubble Space Telescope image features the galaxy LEDA 22057, which is located about 650 ...