Portland, OR

If the clouds do break tonight, you may be in for a treat. The last couple of nights the moon has been in “crescent” mode, that is, it looks like the famous cheshire cat grin.

This cool effect captured by Doug Zubenel in Kansas last month. The odd crescent and shadowed moon effect is called a “Da Vinci Glow.” It was Da Vinci that first explained “Earthshine” which is the cause of this neat-o effect. You can read more about it here, if you’d like. It’s actually an interesting little story.

The moon has been increasing it’s “crescenticity” or “crescentness” or “crescenture” — sorry, I am having a George W. moment — since Sunday night where it was at 2%. Tonight it will be at 12%, so a little bit bigger than a slight sliver that would be a 2% crescent. That last sentence courtesy of Captain Obvious.

In addition to the crescent moon just being kinda cool, tonight the moon moves into conjunction with the Pleiades, or the Seven Sisters. The Pleiades is a group of seven stars, that actually look like six because two of the stars are in rotation with each other. Here is a great picture of all seven (plus a whole lot more).

Photo by amateur astronomer Robert Gendler via NASA’s website.

If you need help finding the Pleiades –well, other than tonight, that is, as the Moon will be right there next to ‘em– the Belt of Orion kind of points to them. If you find the Belt, go right of the line that the Belt creates, and you will find them. Currently, Orion is in the western sky. I used to think that the Pleiades were the terminal point on the horn of Taurus, but this sky map shows otherwise.

So, at sunset, if you can get a clear view of the Western sky, enjoy the view!

Portland, Moon, astronomy, pleiades, seven sisters, Orion, Taurus, crescent moon, NASA, cheshire cat, science, stargazing