The Moon poses near the face of the bull early tomorrow. The face is outlined by the bright stars of the Hyades star cluster -- with one exception. The brightest star is Aldebaran, the bull’s eye. It moves through the galaxy on its own.

Aldebaran is 65 light-years away -- less than half the distance to the Hyades. It’s more than six billion years old -- a couple of billion years older than the Sun. It’s well beyond the prime of life, so it’s puffed up to become a giant. That’s made it especially bright, and caused its surface to shine a vivid orange.

The Hyades includes several giants as well. They’re the brightest lights in the bull’s V-shaped face. But they’re only one-tenth of Aldebaran’s age. They’ve become giants at a younger age because they’re more massive than Aldebaran. Heavier stars burn through their nuclear fuel much faster than lighter stars, so they reach the ends of their lives in a hurry.

One of those stars, Epsilon Tauri, represents the bull’s other eye. It’s more than twice as massive as Aldebaran. It’s still puffing up, though, so over millions of years, it’ll get much bigger and brighter -- giving the bull two impressive eyes.

Look for the face of the bull to the right of the Moon before and during dawn. Aldebaran is separated from the Moon by about the width of your fist held at arm’s length, with the Hyades above and to the right of Aldebaran -- and twice as far away.
 

Script by Damond Benningfield

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