The star El Nath is best known for its position in the sky. It forms the tip of one of the horns of the bull, so it’s nicknamed “the butting one.” And it stands directly opposite the center of the Milky Way Galaxy. But the star itself is interesting in its own right.

What we see as El Nath is a giant. It’s about five times the mass of the Sun, and more than four times the Sun’s diameter. And it shines about 700 times brighter than the Sun.

The word “giant” doesn’t apply only to the star’s size, though. It also describes its phase of life. El Nath is only about a hundred million years old — a few percent the age of the Sun. Because of its extra weight, though, it aged much, much faster. It’s already passed through the prime of life, and is into the next phase. As that phase continues, the star will get even bigger and brighter.

El Nath is also intriguing because there are hints that it has a companion. In one study, astronomers split the star’s light into its individual wavelengths. That produced patterns that are like the star’s “barcode.” But there were hints of a second barcode. If it’s real, then El Nath has a companion star that’s too close and faint to see directly. But so far, no one has been able to confirm a companion for the butting one.

El Nath stands close to the lower right of the Moon this evening. And bright orange Mars is a little farther to the upper left of the Moon. More about Mars tomorrow.
 

Script by Damond Benningfield

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