Hyades Planets

Star clusters are some of an astronomer’s best friends. All of the stars in a cluster were born at the same time, from the same parent cloud of gas and dust. So any differences between the stars must be caused by what’s happening inside the stars themselves. That makes clusters excellent laboratories for studying how stars evolve.

Clusters also can be good laboratories for studying the birth and evolution of planets. And astronomers have found several planets in the Hyades, a cluster that forms the V-shaped face of Taurus, the bull.

They’ve found a giant planet orbiting the giant star Epsilon Tauri, for example. The planet is about seven times the mass of Jupiter, the giant of our own solar system.

Three planets orbit a star in a binary system. The star is a bit smaller than the Sun, and only about 15 percent as bright. One of its planets is the size of Earth, one is a bit bigger than Earth, and the third is almost as big as Neptune. The Earth-size planet is quite close to the star, though, so it’s too hot to be a good home for life. Even so, studying this system may reveal more about how planets are born, and how planetary systems evolve.

Look for the Hyades about a third of the way up the western sky at nightfall, forming a letter V. The brightest star in the V is Aldebaran, the bull’s eye. It’s not actually a member of the Hyades. But the other bright stars of the V are — members of an astronomical laboratory.

Script by Damond Benningfield