Above The Fog: Star Parties on Mt. Tam

It's been foggy in San Francisco. Really foggy. It seems like we have one clear night and six foggy nights per week lately and that is not what an Urban Astronomer likes. So it was with delight that I drove myself and my daughter to Mt. Tamalpais last Saturday for the monthly lecture and star party put on by the San Francisco Amateur Astronomers (SFAA). The Mt. Tam lecture series has been going on for many years and features a wide range of speakers from different areas of astronomy and cosmology.

Following each month's lecture, the SFAA hosts a star party featuring a collection of telescopes, some homemade by SFAA members, pointing out the wonders of the night sky. Despite the foggy conditions in San Francisco and Marin, Mt. Tam is almost always a great vantage point because you are literally "above the fog" and despite the proximity to the city lights of the Bay Area, the viewing conditions on Mt. Tam are quite good. Last Saturday was no exception and the view of the first quarter Moon, Saturn and the spring and summer constellations was great. My daughter and I used an iPhone application called "Star Walk" to help us to identify the fainter stars in Libra and Virgo, to get a full picture of the big summer constellation Ophiuchus, and to even identify part of Centaurus. Using the "Star Walk" application we were able to see that the view from Mt. Tam toward the south was good enough for us to see the upper half of Centaurus and even though we could not see our nearest stellar neighbor, the Alpha Centauri system, we felt like we were nearly there. In fact, it was very interesting to see on my iPhone that the Southern Cross was only a few degrees below the horizon at that moment and even though we can never see it from 37 and 38 degrees north latitude (the Bay Area), I felt like I was *almost* there. I guess I need a vacation at a more southerly latitude ...