The heart of the scorpion is doomed. Sometime in the next million years or so, the star Antares is likely to blow itself apart as a supernova. Only its tiny, dead core will remain.

That same fate awaits several other bright stars in Scorpius. A good example is Acrab — from an Arabic name that means “the scorpion.” It may have not one, but two future supernovas. The star is off to the right of the Moon as darkness falls. It’s at the top of a short line of three stars that represents the scorpion’s head.

Acrab is actually a stellar sextuplet. It consists of two tight pairs of stars, each of which has a distant companion. The two triplets are then bound to each other as well, giving Acrab six stars in all.

Two of those stars appear to be at least 10 times as massive as the Sun. That’s above the weight limit that determines which stars will explode as a supernova. So within a few million years, the cores of each of these stars probably will collapse, and their outer layers will blast into space. For a few weeks, each explosion will shine as brightly as billions of normal stars. After that, the stars will fade from sight.

For now, though, Acrab remains in good view. Look for it to the right of the Moon by about the width of your fist held at arm’s length. Much brighter Antares, the orange star that marks the scorpion’s heart, stands much closer to the Moon. They drop from view about 9:30 or 10.
 

Script by Damond Benningfield

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