10. BRIEF SUMMARY OF SIGHTING One round object, solid green with a flashing red every few seconds. Object was first seen at 20,000 feet (est) and it moved up to 30,000 feet (est) moving back and forth. Object moved Northwest then East over Lake Superior and was seen visually & with binoculars for over 1½ hours. 11. COMMENTS Description, duration, flight path, motion indicate that sighting was probably caused by a balloon.