posted 04-22-2009 07:42 PM            

...an unusual celestial show begins at 5:07 a.m. -- something called an "occultation." This happens when the moon and Venus appear to hover next to each other before the moon fully eclipses Venus.

Tony Cook, astronomical observer for the Griffith Observatory who compiles its Sky Report, said this event would be easy to photograph or videotape in Los Angeles.

"This occultation is only visible from about half the country," he said. "It will be very memorable."

I realized that this would be happening right as I was waking up. Sure enough, I could have watched it through the window from my bed if I'd wanted!

It was weird - one moment, a crescent moon in the dawn sky (already very light) alone. The next, in the dark part of the moon, the dot of light that was Venus appeared!

I took some photos in the most lo-tech way - digital camera on extreme zoom, and also lining up the lens through a pair of binoculars. You can see the little crescent shape of Venus in some of them too.

It really was quite weird to watch something "appear" in the sky in this way.

posted 04-23-2009 08:37 AM               

An occultation can be any object covering another. This one was the Moon and Venus but it can be the Moon and anything else like a planet or star. Astroids will sometimes cover stars and sometimes planets will cover stars. Those are occultations too.

Venus just passed between the Earth and the Sun so through a telescope Venus will currently look like a thin cresent.

You can see that cresent shape in this video.
http://www.eanet.com/kodama/astro/2009/0422/