Or UFO dematerialises , dependant on the observer.

Quote:An Alberta couple captured something on camera Wednesday evening that they can't explain. But they believe it could be a rare weather phenomenon called ball lightning.
“After a rather vicious lightning strike, we saw a ball of fire kind of … about 20 feet above the ground,” Ed Pardy recalled. “And it kind of stayed there in a big round ball.”
Kabi Moulitharan spoke to the couple as well as a scientist about what the video shows.