Bright fast moving "satellite" changes from straight line movement to erratic movement and then disappears abruptlyCountryside, approximately 40 km east of Brussels, Belgium. Hot summer night, clear sky, some 15 minutes after sundown. Walking back from the deer stand (where me and my son of 15 had been observing game) to the car, we saw a fast-moving light in the sky traveling along a straight line from SE to NW. It looked like a bright satellite, it appeared to be very high. Our observation started when it was at around 40 degrees above the horizon, and we took it for a satellite. But at about 80 degrees elevation it suddenly changed its direction by some 45 degrees, and after a view seconds started to move eratically: sudden stops, accelerations, 90-180 degrees turns. After some further 10 seconds doing so it disappeared abruptly. I don't believe it could have been a meteorite or returning spacecraft debris bouncing into the atmosphere.