The Moon looks like it’s rolling through a rack of bowling pins tonight — past the one-pin and heading for the next row, taking dead aim at the star Delta Scorpii. The whole group climbs into good view by about 11 or 11:30.

The one-pin is Antares, the brightest star of Scorpius. It’s close below the Moon. Despite our analogy, the Moon is actually moving toward the bright star, and will be even closer at dawn.

As seen from Earth, Delta Scorpii isn’t quite as bright as Antares. In reality, though, it’s just about as bright. In fact, it’s almost a twin to the Antares system.

Both Antares and Delta Scorpii are binaries — two stars linked by their gravitational pull. Each consists of a supergiant paired with a slightly less impressive star. The supergiants will explode as supernovas — probably within the next million years or so. The companion stars are right along the supernova mass limit, so they might explode, but they might not.

Pi Scorpii is to the right of the Moon. It’s a triple system. It consists of another Antares-like binary linked to a smaller star a long way away.

Antares and Delta and Pi Scorpii are all about the same age — roughly 11 million years to 15 million years. And they’re all members of the same huge complex of gas, dust, and stars. It’s given birth to many supergiants and near supergiants, plus thousands of smaller stars. And many more are taking shape — possible future “bowling pins” for the scorpion.
 

Script by Damond Benningfield

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