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Moon and Companions

October 7, 2015

The crescent Moon drops past a lineup of bright objects in the pre-dawn sky the next couple of days. The array is especially pretty during the first blush of twilight.

The Moon’s companions are arranged in two groups. The group that’s closer to the Moon tomorrow includes the planet Venus and the star Regulus.

Venus is the “morning star,” so you can’t miss it. In fact, it’s just about at its best right now. It was at its absolute brightest for its current morning appearance a couple of weeks ago. It’s faded by only a tiny bit since then, so it’s still a stunner.

And the planet is near its farthest point from the Sun in our sky, so it rises well before sunrise. And it climbs almost straight up as it rises. The combination means Venus pops into view more than three hours before sunrise, and stands high in the east at first light.

Regulus is close to the left or upper left of Venus. It’s less than one percent as bright as Venus — a mere pinprick compared to the brilliant planet.

Yet that difference is an illusion — the result of the great disparity in the distance to the two bodies. Right now, Venus is less than five light-minutes away. In other words, it takes light less than five minutes to travel from Venus to Earth. Regulus, on the other hand, is almost 80 light-years away — more than nine million times farther than Venus — reducing Regulus to a bright speck in the night sky.

More about the Moon and its companions tomorrow.

Script by Damond Benningfield, Copyright 2015

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