The Moon teams up with the heart of the scorpion tonight. It’s their second close approach this month — even closer than the first one. In fact, they’ll get so close that it will look like they could reach out and touch each other.

The scorpion’s heart is the star Antares. It’s much more massive than the Sun, and hundreds of times the Sun’s diameter. Because it’s so puffy, its outer layers are fairly cool, so they shine reddish orange. Unfortunately, the bright Moon will wash out most of that color.

Antares and the Moon team up once every four weeks or so, as the Moon rolls across the background of stars. They were close together on the nights of June 2nd and 3rd, though not as close as they are tonight as seen from North America.

When the geometry is just right, they can appear closer still. In fact, the Moon can pass directly in front of the star, blocking it from view. And it’ll do just that four times this year. Two of them will be visible from all or most of the United States, on the nights of August 24th and November 14th — vanishing acts for frequent companions.

Antares won’t disappear tonight, but it’ll come close. It stands to the lower left of the Moon at nightfall, separated by just two or three degrees, depending on your location. The Moon will slide toward the star during the night. As seen from most of the U.S., they’ll be at their closest about the time they set, a few hours before sunrise.
 

Script by Damond Benningfield

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