While operating an airline flight at 37,000’ both pilots witnessed three lights at very high altitude moving in random patterns.

While operating a B777 from HNL-DEN at 37,000’ both the Captain and I witnessed what appeared to be stars moving at a very high altitude and distance. We were approximately 50 miles SW of Las Vegas at about 0300 local time. The lights appeared to be SE of our position. All three lights were observed to be moving independently in some type of pattern. The lights were the approximate size and brightness of the stars in the background and were steady with no flashing that we typically observe on aircraft. They would each move relatively quickly in one direction for about one minute and then reverse course and move in another direction. We observed this phenomenon for about one hour. We questioned Los Angeles Center about high altitude military activity but they were not aware of any. After about one hour two of the lights continued northbound until they were out of sight. The third light remained for about 20 more minutes before heading southwest bound and disappearing. Over the course of the hour we travelled approximately 500 nautical miles but the lights never appeared to get any closer to us.