Moon and Venus

• ‹ Previous program
• 274 of 1971
• Next program ›

Drag out your binoculars the next couple of evenings to scan for a beautiful but hard-to-see duo: the crescent Moon and the planet Venus. They're quite low in the southwest at sunset, so they're tough to spot in the bright twilight -- hence the need for binoculars.

Venus is actually quite bright. The planet is close to the Sun, so it receives a lot of sunlight. Clouds completely blanket the planet, and they reflect most of the sunlight that strikes them. And finally, Venus is fairly close to Earth, so a lot of that light reflects our way. Put it all together, and Venus is the brightest object in the night sky other than the Moon.

And like the Moon, Venus goes through phases as seen from Earth. Sometimes it lines up on the opposite side of the Sun from Earth, so it's full. Other times, it passes between Earth and Sun, so it forms a thin crescent. It's coming out from behind the Sun now, so it's in a gibbous phase -- the opposite of the Moon's phase right now.

Over the next few months, thanks to the combined motions of Venus and Earth, sunlight will illuminate less and less of the portion of Venus that faces our way. But at the same time, Venus will be getting closer to us, so it'll get brighter.

For now, look for Venus quite low in the southwest beginning shortly after sunset. The Moon will be a little to its lower left this evening, and tough to see. It'll be in slightly better view tomorrow, well to the left of Venus.

Script by Damond Benningfield, Copyright 2008

For more skywatching tips, astronomy news, and much more, read StarDate magazine.