Get up early on the morning of Thursday, March 27, and you’ll be rewarded with a picturesque view of the moon with planet Venus in the eastern sky. They’ll be worth getting up for – the brightest and second-brightest orbs of nighttime – near each other on the sky’s dome.
Of course, the moon and Venus aren’t really that close together in space. The moon lies about 1.2 light-seconds away while Venus right now lies some 6 light-minutes distant from Earth. Light travels at about 300,000 kilometers (186,000 miles) per second, or about 18,000,000 kilometers (or 11,000,000 miles) per minute. Or another way of looking at it, Venus is nearly 300 times farther away than the moon on the morning of March 27. And that is why Venus, a planet as large as Earth, appears as a point in our sky, while the moon, only a quarter of Earth’s size, looks like a round disk.
Both of these worlds – the moon and Venus – shine by reflecting the light of the sun. Sunlight reflected by Venus’ cloud cover takes about 6 minutes to reach Earth, while the sunlight reflected from the moon’s surface takes only a little over one second to reach us.
There’s another reason to get up early tomorrow. Closely look at the waning crescent moon with the unaided eye or binoculars, and you’ll likely see earthshine: the faint glow of twice-reflected sunshine on the nighttime side of the moon.
In the final days of March 2014, the moon is waning and heading closer and closer to the sunrise point on the horizon. At northerly latitudes – like those in the United States, Canada and mid-northern Asia – the mornings of March 27 and 28 may well be your last chance to see the moon in the March 2014 morning sky.
At southerly latitudes, on the other hand, it’s quite possible you’ll see the waning crescent moon on the mornings of March 29 and even March 30, as well. Click here to learn why those in the Southern Hemisphere can see the waning crescent moon longer in the March morning sky than we can at northerly altitudes.
Bottom line: No matter where you live on this great globe of Earth, watch for a beautiful morning couple – the moon and brightest planet Venus – to waltz in the ballroom of dawn on Thursday, March 27.