I will tell you what three of my friends and I saw some years ago ( it was the time of the first Irak war), lying on the river "Isar" in Munich, Germany. It was around midnight in August. We were talking about meteorits and with us was a girl which has never seen a shooting star in her live when she suddenly asked: Well - is that one of them? We looked up to the sky and short above the wood on the other side of the river there were three lightballs, shimmering in different colours, flying in a triangle formation, all the waydown the river to the east in a constant height. They were not very fast. But they have been for sure no airplanes. It seemed to be two or three miles away and for this distance it must have been very big.