International Observe The Moon Night 2017
Photo credit: Jim Hendrickson
Saturday, 28th October, is International Observe The Moon Night! This annual event encourages people to get outside in the early evening and take a gander at Earth’s nearest neighbor in space. Here’s how the Moon will look this evening, using the Scientific Visualization Studio's Dial-a-Moon online app:
Here are a few things to notice about the Moon if you view it through binoculars or a telescope. First, the Moon is in the waxing gibbous phase tonight, between first quarter and full. This means it is a little more than one-fourth the way along its orbit, taking the start to be when the Moon is “new” (seen roughly in the direction of the Sun in the sky). The vertical line running down the middle of the Moon’s disk is the terminator, representing where the Sun is just coming up over the horizon on the Moon. Terrain is seen is sharpest relief near the line, since shadows cast by tall objects tend to be longest there.
Look for the lunar “seas”: the dark spots that form the familiar “Man in the Moon” pattern are remnants of giant impact basins that were filled in by lava early in the Moon’s history. Some of these are ringed by tall mountains, forming the rims of craters hundreds of miles across. And of course, much of the Moon’s ancient “southern highlands” terrain is covered in countless impact craters. These preserve a record of billions of years of lunar history shaped by the rain of comets and asteroids from above. Also, look for subtle shades of color on the lunar surface -- they’re real!
Lunar Reconnaissance Orbiter true-color image of the Moon.
If you don’t have access to a telescope or a pair of binoculars, there is still plenty to see with just your own eyes. And don’t forget the Earth around you. How bright is moonlight? We still don’t quite know exactly. Look at how the illumination changes in the evening, as the glow of twilight fades in the west and the Moon becomes the dominant source of light in the night sky. Some animals are more active at night when the moon is brightest.
Lastly, think about the human element. How do people relate to the Moon? Are they more or less likely to notice it during some parts of the lunar cycle? Consider, too, that we may owe our very existence to the fact that the Earth has a large moon at all.
From the newbie to the most seasoned lunar observer, International Observe the Moon Night offers something for everyone. See it tonight!
