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Moon and Scorpion

StarDate: 
January 17, 2023

Antares is one of the more impressive stars in the galaxy. It’s about a dozen times more massive than the Sun, 700 times wider, and almost a hundred thousand times brighter. Yet it has some brothers and sisters that are even heavier. They don’t look as impressive right now, but they will before long.

Antares is the orange heart of Scorpius. It stands just a whisker from the crescent Moon at dawn tomorrow. It’s flanked by two of those impressive siblings. Tau Scorpii is close below Antares, with Sigma Scorpii above it.

All three systems were born in a region known as Upper Scorpius. Over the past 12 million years or so, it’s given birth to thousands of stars. And quite a few of them are big and heavy.

Tau Scorpii, for example, is more massive than Antares. It’s not nearly as bright, though, because it’s millions of years younger. Antares has gone through a series of changes that have caused it to puff up to become a supergiant. Tau hasn’t reached that stage of life. But it will in the next couple of million years or so. When it does, it’ll shine even brighter than Antares does today.

Sigma Scorpii is a system of at least four stars — one of which is about 18 times the Sun’s mass. So when it puffs up, it’ll be even brighter than Tau.

Antares, Tau, and Sigma all face the same fate. Each star will explode as a supernova — blasting itself to bits and briefly shining as brightly as billions of Suns.

Script by Damond Benningfield

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