Star Trails From Mount Hamilton

Last week there was a magnetic storm watch that raised the possibility of seeing the Northern Lights from the US. Having previously consulted some dark sky finding websites, I knew that Mount Hamilton outside of San Jose is one of the better places to observe the stars from in the bay area. Unfortunately, the storm watch was canceled, but I still went up the mountain with a couple friends.

If you're wondering what's going on in this photo, well, you're probably new to the world of star trail photography. Basically, as the earth rotates the stars in the sky appear to move, so if you take a ton of photos over a period of time, and overlay them on top of each other, you get the effect of the stars moving through the sky, as in this photo here.

Photo Details: 24mm f/2.2, ISO 800 @ 20.0s exposure. 186 images stacked.