The gibbous Moon lines up between two bright stars tonight, with an even brighter star not far away. The Moon will move toward the faintest of the three stars during the night.

As night falls, Aldebaran will stand to the right of the Moon. El Nath — the “butting one” — will be closer to the left of the Moon. And brilliant Capella will be well to the upper left of the Moon.

The closer stars both belong to the classic outline of Taurus, the bull. Aldebaran is the bull’s orange eye, while El Nath marks the tip of one of its horns.

But El Nath also belongs to the outline of Auriga the charioteer. Officially, it’s a member of that constellation, and not Taurus. In fact, it’s the second-brightest star in the whole constellation, after Capella.

When the constellations were first drawn, thousands of years ago, it really didn’t make much difference if one star had a dual identity. But about a century ago, astronomers created precise boundaries for each constellation. So while a star could remain part of two star pictures — the outlines of two different figures in the sky — it was given just one official residence. In the case of El Nath, it’s Auriga.

Although El Nath is fainter than the other two stars, the Moon will scoot closer to it during the night. They’ll be pretty close together at first light — making the star with two constellations even easier to pick out.

We’ll talk about Capella tomorrow.
 

Script by Damond Benningfield