Hercules is a constellation of the Northern Hemisphere between Corona Borealis and Lyra. It is best seen high overhead in summer. The red star marking the head of Hercules lies toward the south. It is actually a pair of stars (see Binary star ). The red star is a giant, hundreds of times larger than the sun. In the northwest side of Hercules, a cluster numbering more than 100,000 stars appears. It is so far away that its light requires more than 30,000 years to reach the earth. Even under good conditions, the cluster is barely visible to the naked eye. In 1934, a star in Hercules exploded, throwing huge masses of gas and dust into space. As a result, the star suddenly became much brighter. Such an explosion is called a nova. The star has since faded to its normal brightness.
