Most exploded over an ocean, and too high in the atmosphere to do damage, but evidence is mounting that asteroid impacts are more frequent than once believed.
In the middle of little-known nebula Gum 41, brilliant hot young stars are giving off energetic radiation that causes the surrounding hydrogen to glow red.
The first Earth-sized exoplanet orbiting within the habitable zone of another star has been confirmed. The new planet, dubbed Kepler-186f, was discovered using NASA’s Kepler telescope.