Yes, it's possible to capture an interesting night-sky photograph in Los Angeles with a simple consumer mirrorless digital camera and a tripod, but you need to be lucky and patient.

This extremely bright comet was found by the PanSTARRS project in 2011 and just barely became visible over Los Angeles in 2013. I captured this photo an hour after sunset at 19:57 PDT on 12 March 2013. (This file is a lossy JPEG with Exif data intact. I submitted a lossless PNG to Wikimedia Commons.)