Saturday, December 29, 2012


If you've been outside after dark the past month and had clear skies to the east, you must have noticed the planet Jupiter, the brightest nighttime "star" right now. It's near the red giant Aldebaran, which makes for a pretty pair. On Christmas day the Moon swept close to Jupiter in the sky, and in fact observers in South America could watch the Moon actually pass in front of the planet. Astronomer Rafael Defavari had his telescope set up to record it. The first part of the video shows Jupiter disappearing behind the Moon, while the second part shows it emerging from the other side.

This sort of alignment, called an "occultation," isn't especially rare. The Moon and planets lie on roughly the same plane in the sky so they line up occasionally (though not exactly the same plane, or similar occultations would happen several times a month). Still, I found this video unexpectedly beautiful and moving. For me it drives home the truth that we really are sitting on a round rock in space watching other rocks and balls of gas circle the Sun in a cosmic dance. Though the video is silent, I couldn't help but hear the soundtrack from "2001: A Space Odyssey" in my mind (specifically, Ligeti's Lux Aeterna, though another piece may pop into yours).

Look up once in a while and enjoy the dance.


Sherwood Harrington said...

Breathtaking. I was startled by the clarity.

To me, on first viewing, the egress part had an even greater "wow" factor than ingress because of the Galilean satellite's emergence just before the planet's. But wonderful all around.

Thanks, Brian. I hadn't been aware of this.

Brian Fies said...

I agree. Ingress is neat because you can't see the unlit limb of the Moon so it comes as a bit of a surprise, but watching that moon rise just before Jupiter glides into view looks like something out of a science fiction film. A good one.

Jim O'Kane said...

Beautiful stuff. I was taking pictures in New England before Jupiter traded places in the sky with the Moon, and a friend of mine in L.A. posted a pic just after the swap.

Quite a head rush to think about looking at those solar system thingies rolling around up there, while people we know are seeing slightly different views because we're each standing on a different part of the ball we call home. Great post!