Clear Skies!

Amateur astronomers often sign off an email or message with the phrase "Clear Skies" because anyone interested in enjoying the night sky needs to have a clear sky to start with. I often close blog posts on this blog with the phrase "Clear Skies!" as a kind of wishful thinking and good luck charm.

Right now in San Francisco, I need all the good luck I can get. The coastal weather pattern each summer ensures that clear skies will be rare indeed, especially in the Outer Richmond district where I live. So I have had precious few viewing opportunities from my own backyard this summer, and the San Francisco Amateur Astronomers have been forced to cancel most of their "City Star Parties" that take place near Lands End on the western side of the city, due to fog.

Venus and the sunset sky

When we get the rare clear sky, or when I am in another part of the Bay Area and am enjoying a stunning view of the western horizon just after sunset, I am reminded why I love astronomy; the beautiful changing color of the sunset sky, and the gradual transition into night, and the dazzling light of Venus in the west, all combine to motivate me to look up in the sky, and more than ever, I appreciate the clear skies that usually are available here in the Bay Area.

So to all of you, I wish you "Clear Skies" and a warm night somewhere this summer to enjoy the heavens.

Image courtesy Pete Lawrence.

The Five Visible Planets

As an amateur astronomer and public speaker, I find the five visible planets fascinating. These 'wanderers

The Solar System

' are beautiful to watch with the naked eye, and are interesting in a telescope as well, even in a big city. Consequently, I am a close watcher of the changing motions and of these bodies, and I point them out often to groups at star parties. The planets all follow the band of the Zodiac across the sky, of course, because they move along the ecliptic, the projection of the orbits of all of the Solar System planets across the sky. And as such, their motion is interesting to watch, whether they are the inner planets of Venus and Mercury with their unusual twilight appearances, or the outer planets of Mars and Jupiter and Saturn, enjoying long seasons in the limelight of the night sky. 

We just had some interesting patterns of planets and stars, and of course can always enjoy those by knowing where to look for the five visible planets. Earth Sky has a fine article on these planets for July.