Me and a friend were camped out just south of Mt. Yoran at Divide Lake located in the Diamond Peak Wilderness. This is about five miles from the nearest trail head in the Oregon Cascades mountains. The wilderness area is located just south of the Willamette Pass Ski Area located along Highway 58. We were camped at the base of Mt. Yoran which is a rocky volcanic plug located just north of Diamond Peak.We were in our sleeping bags looking up at a perfectly clear fully dark night sky. There were no other campers or any other source of light. We had a clear view of the sky and the dark spire outline of Mt. Yoran to our north with no obstructions. From our camp site to the top of Yoran is less than 1000 feet.As we looked up a bright light came into view above Mt. Yoran. From our perspective the angle of view was approximately 50 - 55 degrees above us to the north. The object was pure white and at least 10 times the brightness and apparent diameter of any stellar object in the sky. It moved smoothly and silently. There were no flashing lights or any other sign of it being a conventional aircraft.As the light moved south it made a smooth sweeping crescent shaped arc to the east and eventually turned back to the north to disappear behind the black silhouette of Mt. Yoran. The entire period of visibility was fairly short, but what could not be easily explained includes several interesting points:1. The flight pattern was not normal for regional jets or local aircraft from the small Oakridge or Odell airport/landing strips, and there was no sound of any kind.2. The Willamette Pass Ski area could receive an emergency medical helicopter, but it is so close to Mt. Yoran that any such aircraft would have been noticeable from just below Mt. Yoran.3. The object appeared to come in over Mt. Yoran and turn to the east and then north all the while staying over the visual space of Mt. Yoran from our angle of view. No high altitude object would have been able to turn in such an arc. It also could not have been an astronomical object since it moved slowly and turned smoothly all the while remaining pure white and not changing in intensity, color, or size.4. We debated the visual clues that night and the next day to understand what we had seen. Nothing we could come up with matched the visual facts since we had a clear view with a large rocky peak to compare direction and size with.5. The object moved eloquently as if under precise control. It curving flight was mathmatical in its smoothness and it was moving much slower than a shooting star, much faster than a high altitude jet or large orbital object like the International Space Station (which I have observed on several occassions by the way.)6. I personally was in the Air Force for four years and have countless hours of night time flight line experience observing every manner of aircraft. This was not not similar to any winged aircraft.The top 100 feet of Mt. Yoran represents an area of approximately an acre in total horizontal space. From our point of view, it appeared the object was within several hundred feet of the summit and could have been up to 50 feet in diameter if it was as close as it appeared to Yoran's rocky spire.I have attached a photo showing Divide Lake and Mt. Yoran from the angle we observed the object. Our camp was located at the north end of the small lake closest to the lower slope of the mountain.