11 July 2010

A Must See: Four Planets and the Moon

This week the sky features four of the brightest planets in a beautiful lineup in the sunset sky. The illustration on the left, borrowed from Sky & Telescope Magazine, demonstrates how the planets all align themselves in a path across the sky known as the Ecliptic. This line in the sky, actually a gentle curve from west to east across the south part of the sky, is the plane of the Solar System as viewed from our observing platform on Earth. We see fast-moving Mercury close to the Sun, then Venus, Mars and Saturn, a most impressive line-up.

To set this into perspective, the young Moon emerges from the glare of the Sun on Tuesday 13th, moving somewhat parallel to the Ecliptic but each day a bit farther south of the Ecliptic. This is because the orbit of the Moon around the Earth is slightly inclined to the rest of the bodies in the Solar System. And as we just had a Total Solar Eclipse on Sunday, the Moon is following a path away from the Ecliptic into what is called the "descending node" south of the Ecliptic.

I will be talking about this at the California Academy of Sciences at their Nightlife event this Thursday in Golden Gate Park. If you are in or near San Francisco, please join me on the roof for Star Tours!


Sidewalk Universe said...

Hey Paul nice write up here - this is going to be a neat show indeed.

Have fun on the roof top Thursday night and stay away from the ledge! I would really enjoy and wish I could hear your talk.

Ron said...

I know a brilliant philosopher and astronomer who contributed a lot in the field of astronomy and philosophy. He’s name was Guillermo Haro.
Guillermo Haro was very famous, and at the same time, very influential in the development of astronomy in Mexico, not only because of his own astronomical research but also by helping in the promotion of the development of new institutions for astronomy. Moreover, he defined modern astrophysical research in Mexico where he paved the way to various initial lines of research and established general scientific policies.