12 October 2009

Planetary Motion

The morning sky continues to be a busy place, showcasing just how much action is taking place in the Solar System. Saturn, a relatively slow moving outer planet is gradually rising up in the east, emerging each morning a minute or two earlier so that it will soon be a true morning star. As it graces the dawn sky just ahead of the sunrise, it is encountering the two fast-moving inner planets, Venus and Mercury. This week they have close encounters and beautiful alignments that will be a sight to see. The illustrations provide a sense of how far Venus and Mercury move over the course of just a few days. The passing of the waning Moon on the mornings of the 15th and 16th add a nice touch to an already impressive lineup of Solar System objects.


Britt said...

I saw what looked like to be a comet or maybe it was just a shooting star this morning driving south on 101 around 7:00am coming out of san francisco, around Caesar Chavez, on 10/16. Did anyone one else see this and know what is was?

The Urban Astronomer said...

Sounds like an interesting thing you saw, Britt. If you saw a bright light to the south (roughly the direction of travel when you are at 101 and Caesar Chavez) you might have been looking at the brightest star in the sky, Sirius. Or it might have been the Space Station which is making a series of early morning flyovers. I didn't see it because it was foggy here in my part of San Francisco.

I hope you see more cool stuff in the sky in the coming days. Late October it stays dark quite late in the morning and Venus and the other planets will continue to shine brightly before sunrise.