Pinpoint of light grows larger and shines bright blue/white and staggers it's course.Every year I go to the Owens river valley in Northern California with my Father and Cousin. We were on glass mountain between Bishop and Mammoth Lakes. Before going to sleep, we watch the sky for a few hours looking for satellites and ufo's. On Saturday night, my cousin spotted a pinpoint of light traveling from west to east. We assumed it was a satellite at first (object too high to be conventional aircraft). After a few seconds of watching, it seemed to grow in size about like a dime held out at arms length and it lit up bright blue/white (like when someone is arc welding) and it's course became staggered for a few seconds untill it returned to a pinpoint of light. After that it just continued on it's way. Our elevation on the mountain was approx 8000ft. the sky was crystal clear, the temperature was around 51deg with a very light wind. There were no other aircraft in the vicinity at that exact time. We did see several satellites the entire week we were there. I've been a sky watcher since my first ufo sighting at age 7. After seeing 12 now, I strongly believe we are not alone, never have been and never will be.