Catch the full moon tonight (12 Dec) if you can

[Kevin]

Tonight is a full moon and if you have clear skies you should try and catch a peek at it because it could be up to 14% larger and 30% brighter than any other full moon this year.

This is because tonight's full moon happens to correspond to the moon being at it's perihelion (the closest point to the earth in it's elliptical orbit). This only happens once every few years and tonight happens to be one of those times.

Now I say take a look if you can but don't expect to see anything really major. The human eye isn't that great at detecting differences of these levels, but still it's an astronomical phenomenon that you don't get too many chances to experience so I figured I'd make a note of it. And the most striking time to watch is when it's rising or setting because of psychological effects, the mind always interprets the moon as bigger when close to the horizon, this is actually called the moon illusion.

So anyway, just a silly little thing that I find neat.

[Rhydderch Hael]

Perigee, not perihelion.

—gee means in relation to Earth. Perigee is the orbital point closest to Earth. —helion pertains to the sun. Perihelion is the point closest to Sol.

—lune applies to an orbit with the Moon itself. Perilune is the closest point a satellite reaches when orbiting the Moon.

—apsis is the generic label, if you were writng some sci-fi and wanted to describe the orbital relationship around some alien planet.

[Bolty]

Perigee, not perihelion.

I love this website.

-Bolty

[DeeBye]

And the most striking time to watch is when it's rising or setting because of psychological effects, the mind always interprets the moon as bigger when close to the horizon, this is actually called the moon illusion.

I was going to post a link to an article that debunked the psychological effect of the moon appearing larger when it is closer to the horizon (I read it once I swear!), but it turns out that there are a boatload of reasons why the moon appears larger when it's closer to the horizon. You geeks will love this link because it is full of graphs, overly complex explanations, and an ugly colour scheme.

http://www.lhup.edu/~dsimanek/3d/moonillu.htm

I saw the moon last night, and it was glorious. It was a clear night and the ground was covered with snow, so the moonlight was doubly bright.

[Rhydderch Hael]

I love this website.

-Bolty

You're not getting my beer, son.

Wiki has, what I feel, is a nice partial list of all the weird and cool names they'd use when talking about the orbits of planets and other heavenly bodies (I notice the lack of 'periwowza', the closest point you can get to Charlize Theron)

Incidentally, Earth's perihelion is coming up in a few weeks.