When it comes to Astrophotography, and night shots in general, planning is everything. I planned my trip to Mono Lake based on having a 3-day holiday weekend, but what I didn't realize was that it was a full moon that weekend. If you've never been in an area with dark skies before, you might not realize just how much light the moon reflects back to earth. You could walk around outside at midnight, and see pretty well thanks to all that moonlight.
Even if it's not a full moon, if you're planning on shooting a time lapse at night, or star trails, you should always plan for the position of the moon throughout the night, to make sure it doesn't interfere with your exposures. I learned this the hard way when trying to do a time lapse in the dark skies over Namibia.
The tufa columns in the South Tufa area of Mono Lake make for some unique photos. I was hoping to get a really great shot with the stars shimmering above them, but unfortunately that didn't quite happen due to the full moon. You shoot, you learn.
Star and moon-lit tufa columns.