“Leo Grenier, director of Muskegon’s National Weather Service office, says he knows what happened – but he won’t tell. “There wasn’t any UFO,” Grenier said. “There’s an earthly explanation but I’m not going to talk about it.” The reason, Grenier said, is national security. “I was in the Navy for 20 years. I know a lot of Navy operations and a good bit (about) Navy equipment. I checked with some retired electronic technicians I know, and they confirmed what I thought.”