The world's biggest lamp shade is formed by the marine layer clouds as they roll in off of the San Diego coast, covering the lights of the cities below Palomar. Here's the view from last night just after 11 p.m.
During the night, after I took this shot, the clouds got thicker and advanced further inland making it even darker. Astronomers need dark skies. I took this shot after returning from a street lighting demonstration in the City of San Diego.
The City long ago gave up on astronomy-friendly low-pressure sodium lighting for high-pressure sodium and is again exploring making changes in their street lights.* Under consideration are induction and LED lights, both of which are very white in color. I'll be attending a meeting to learn more about this later today and will soon share my photos form the session last night.
Tonight the general public gets a chance to evaluate the new lights. The public survey to evaluate the lighting on 6th and Laurel begins at 7:30 p.m. If you are interested meet at the War Memorial Building.
If you live in the area you should try to have a look and give an opinion.
*Actually, for locations within 30 miles of Palomar and the Mount Laguna Observatory they have been sticking to low-pressure sodium.