Hercules, a constellation of the Northern Hemisphere. It is best seen during the summer. It was represented by the ancient Greeks as the kneeling figure of the hero Hercules. Near the western edge is the globular star cluster Messier 13, comprising more than 50,000 stars about 30,000 light-years from the earth. Only a few stars of Hercules are brighter than fourth magnitude.
Hundred of meteors fly across the sky every night, but only a few make it to Earth. Meteors are best known for the brilliant streaks of light they make as they burn up in the atmosphere. Learn about 10 memorable meteor crashes that left an impression.
We know it's not made of green cheese, but what are the origins of the moon? Learn astronomers' theories about where the moon came from.