Disc flares and disappears over Mt. Timpanogos, UT 4 Sep 12A friend and I went camping Tues 4 Sep in what's known as the Alpine Loop in the Wasatch Mountains. About 8:30pm Mountain Time, as we started looking up to see the stars, I noticed what I originally thought was a planet - in the NW sky about 45-55 degrees from horizon (I'm no astronomer so I don't know how to describe the coordinates any better than that).This "planet" flared suddenly and brightened and grew considerably - I would estimate at peak it appeared the size of 2-3 Venuses. Magnitude was what I'd expect if Venus grew that large.The flare turned a pinkish color - to the point it looked like a "mini carnation" flower in the sky.It faded to nothing within 5 seconds or less.Sky condition was completely clear - esp. so as we were at an elevation of 7100 ft.I wrote to a sky phenomenon web site - their best guess was an Iridium satellite flare; but none were visible in UT at that hour and date.I'm wondering if anyone else has reported seeing this phenomenon - we know we both saw something - but it defies any description.