There are two incidents to report, the first was approximately 30 years ago, my 10 year old son was dong a report for school on constellations. As we (my son, my wife and I) stood on our darkened deck in front of our house and looked at the sky for the various constellations he needed to observe we noticed a light that I thought was a high flying jet at least that was what I told my son it was when he pointed it out to me. Then we noticed a second light, similar to the first that appeared to be on a collision course. I explained to my son that they were at different altitudes and it was not a danger that they should converge in the sky. Seconds later after making this explanation to my son it became clear that there was a third converging light and that they were all going to intersect, each forming a 120 degree angle with each other. I explained to my son that this was a much more rare occurrence but that it was no big deal they would all pass over or under the other and continue on. We all watched carefully, me more incredulous than the other two because I am a pilot and I had only seen two aircraft intersect like this before, never three. But what came next was even more impressive. The three came together and rather than continuing on they appeared to bounce off of each other and gain significantly in velocity. I stood there with my mouth agape trying in vain to explain what I had just witnessed. Then as we watched the lights move away from the convergence point they seemed to slow down as they grew nearer to the horizon, then slow to a stop and start moving back toward the convergence point again. This time they came together accelerating visibly and again they seemed to bounce off each other and reverse course right back to very near the horizon again, and to repeat the slowing down, stop and accelerate toward each other again. Kind of like watching two Dall Sheep banging heads together. But this time the velocity was much faster perhaps taking only a second or two from the time of the stop to the time of the convergence. But this third time proved to be the last as when they converged they accelerated to past the horizon and well over the tops of the mountains to the north, southeast and southwest of Anchorage. I only report this now as my son was doing a similar sky-watching and constellation observing session with his 12 year old daughter just a few days ago. I did not see this second and most recent UFL sighting. These lights in the sky must not have been objects as I understand it. There was no noise, no explosion, no obvious exhaust and no sonic booms. At the height these objects were flying they clearly were breaking the speed of sound, but no noise was heard at all. I wonder if anybody else in the Anchorage area has ever seen such an incident. All I could tell my son and wife was darned if I know. I didn't actually say darned but you don't need my colorful language for this report. I wish I had been there for the second incident, I nearly always have my smartphone handy these days. Sorry to say, I don't have anything to back up what I saw. Just the honest observation of common citizens.