Orange orbs in northwestern Colorado/Steamboat Springs skyOverview: At almost exactly midnight, myself and three others witnessed several bright orange (about the intensity of Venus), flickering/pulsating orbs starting around the west/northwest horizon, and moved to ~45-60 degrees (deg.) in the western sky, then to the south at altitude.Detail: The first orb was seen at just after 12am, starting at the horizon to the west. It was very bright orange that seemed to flicker instead of strobe or blink. As it moved higher in the sky (~20 deg. elevation), a second orb that looked exactly the same started from the same area on the horizon, and followed the first. Then after about one minute of flight the second orb changed direction, and circled below the first orb (with several degrees of separation in the sky between the two).As the first orb moved to ~45 deg. in the sky, it started to move south, then it faded away (darkened) until it was not observable. The total time it took from start to finish was between 2-3 minutes. As the first orb disappeared, the second was still visible between 20-30 deg. in the sky, and then it faded out ~1 minute after the first.After the first two disappeared, ~2 minutes later a third started from the about same location on the horizon, and had a flight path similar to the first. It moved almost straight up to ~45 deg. elevation, then veered south, and faded out after ~2-3 minutes at ~60 deg. elevation in the west-southwest sky.The only time there was more than one orb in the sky were the first two; after that they only appeared one at a time, with ~6 minutes total from the start of one to the other (~3 minutes of visible flight, then ~3 minutes until the next one started) Conclusion: We witnessed several more (at least 10 total) over the span of ~50 minutes, starting from around the same location on the horizon, then move in a similar flight pattern to the first and third orbs. After they stopped we went inside, so there could have been more later.Although they weren't in any discernible formation, they did all fly approximately the same flight pattern and had approx. the same start/finish position. It was hard to get any reference to altitude, speed, or distance against the dark sky; but I would guess they were flying anywhere from 1000-2000 feet above the ground. They didn't make any erratic movements, no sound, and their speed seemed fairly slow to moderate.There were aircraft in the area at the time; but they were most likely just commercial/small aircraft that weren't involved with the sightings (they didn't seem to be following/intercepting them). Although, they did give a good reference as the lights on the aircraft were 100% different then the orbs. We also could hear the aircraft but not the orbs, and the orbs seemed to move slower across the sky compared to the aircraft.Extra details: From our position we couldn't directly see the horizon as the buildings/trees were obscuring it; so I can't 100% know if they started in mid-air or from the ground. This to me is the biggest factor, as if they started from below the horizon the there's a 90% probability they were something man-made i.e. Chinese/sky lanterns. But from where we observed them it seemed they started either right at or just above the horizon, making them harder to I.D.I do have a military background (U.S. Navy 2000-2004) with an honorable discharge. I have also studied military equipment/aircraft throughout the years, and these did not act or look like any kind of aircraft or other manned object. The other three witnesses (my co-workers) are credible with good work ethics. One is even a skeptic that was trying to explain them as aircraft lights, but I'm 99% sure they weren't manned aircraft.I have also seen a UFO while in the service in 2003, but it had different characteristics than these.