Was at an outdoor party in a suburban area of Holyoke. Looking between the houses and up, I saw a very bright red light very high up in the sky. It was twice the magnitude of brightness of Venus at its brightest, and twice the size of Venus at least. At first I thought it was Mars, but realized 1. Mars is never that bright. 2. It was in an area of the sky Mars could not be in (straight overhead). Then things got weird. It started to move towards the north, but extremely slowly. Then it wavered from side to side in a herky jerky fashion. While doing this it started to fade in brightness. Its color went from intense bright red to dull red to a faded light green. As it faded, it almost looked like you could possibly make out a structure had binoculars been available (they weren't). One other person witnessed this and filmed it, commenting that it certainly was not a plane and was exhibiting strange movements. I watched the sky for a good five minutes after it faded to see if it returned. It did not. Then roughly 15-20 minutes later, it was back, and in the exact same position. This time it moved in the same stuttering side to side fashion as it headed north again, but faded very quickly this time, if it turned pale green it was not apparent this time. I again watched the part of the sky it disappeared in, but it did not return. Time of first sighting, roughly 2-3 minutes. Time of second sighting about 45 seconds-1 minute. It did not reappear. Things it could not have been: Mars, airplane, balloon with laser (would have been not enough time to get the thing down, restart the laser, and get it to that height again, also would have to have been a fairly powerful laser), chinese lantern hot air candle balloon. It appeared to be at least a half a mile up minimum. Could have been a drone, but the stuttering motion while moving would seem to preclude that as well. No sound.