Bright lights encircle the crescent Moon during the early dawn twilight tomorrow – the star Antares and the planets Venus and Mercury.

Antares appears closer to the Moon than the other two companions. From most of the United States, only a sliver of sky will separate them at first light. For skywatchers in the western part of the country, though, that sliver will disappear as the Moon occults Antares. The Moon will cross between Earth and the star, blocking it from view.

Antares occultations come in groups. They’re tied to an 18.6-year cycle in which the Moon moves farthest north and south across the sky. The current group started last year, and continues into 2028. The next series won’t begin until 2041. But only some of the occultations will be visible from the U.S.

The Moon’s brightest companion is the planet Venus, the “morning star.” Venus is dropping back toward the Sun in our sky, but it’ll take its time. It will remain in view until April. After that, it’ll pass behind the Sun, then hide in the Sun’s glare. It’ll return to view – as the “evening star” – in July.

Mercury is the Moon’s farthest companion tonight. It’s the closest planet to the Sun, so it never moves far from the Sun in our sky. In fact, this is one of its best appearances of the year. It looks like a bright star well to the lower left of the Moon. But it will be much closer to the Moon on Tuesday morning. More about that tomorrow.
 

Script by Damond Benningfield

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