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Moon and Venus

January 9, 2013

The days have been getting longer since the winter solstice three weeks ago. The extra daylight has all been tacked on to the end of the day. Sunrise has continued to come a little later each day for much of the United States. The Sun is just now beginning to reverse that trend and rise a little earlier.

For skywatchers, the benefit of that arrangement is that you don’t have to get up all that early to enjoy the delights of the dawn sky. Tomorrow is a good example, with the Moon and the planet Venus quite low in the sky at first light. Venus is the brilliant “morning star,” to the right of the crescent Moon. The combination of Venus and the Moon shining through the early blush of twilight paints a beautiful tableau.

Another beautiful aspect of the view is the non-crescent portion of the Moon — the part of the lunar surface that’s not bathed in sunshine. It still shines through, though, because it’s bathed in earthshine — sunlight reflected off our own planet. That light makes the bulk of the Moon look like a ghostly apparition framed by the crescent.

That light comes from an almost-full Earth suspended in the lunar sky, shining so brightly that it would almost hurt to look at it. In fact, Earth will be full as seen from the Moon on Friday, when the Moon is new — it crosses between Earth and Sun, and is hidden in the Sun’s glare. It’ll return to view by Sunday, this time as a thin crescent in the early evening sky.

Script by Damond Benningfield

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