A thin crescent Moon slides past a tight pair of planets in the early evening sky the next couple of nights. The Moon will be hard to find tonight, but much easier tomorrow night.

Venus is the brighter planet — the spectacular “evening star.” Its companion is Saturn. Tonight, the two planets look like they’re about to touch each other. They’re low in the southwestern sky in early twilight.

The Moon is below them. It’s so low in the sky that anything along the horizon will block it from view. And even if your horizon is clear, the Moon might be tough to find. That’s because it’s just more than a day past “new,” when it crossed between Earth and the Sun. Only about two percent of the lunar hemisphere that faces our way is in sunlight, so it’s the barest of crescents.

The entire lunar disk should be visible, though, because it’s lit up by earthshine — sunlight reflected from our own planet. If you were standing on the Moon and looking back in our direction, you’d see an almost-full Earth. It would shine more than 40 times brighter than a full Moon. So the lunar night would be quite bright.

By tomorrow night, the Moon will have moved past Venus and Saturn, which will have opened up a little separation between themselves. The Moon will be a slightly fatter crescent, so it’ll be easier to find and follow. The three worlds will form a beautiful trio as the color of twilight fades away.

Tomorrow: a lopsided halo.

Script by Damond Benningfield

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