Nuclear alien UFO from North Korea pic.twitter.com/GUIHpKkkp5— Elon Musk (@elonmusk) December 23, 2017
Many people thought it could be aliens or an attack from North Korea, so Elon played on those assumptions in his tweet.
Before the Falcon 9 rocket was launched from Vandenberg Air Force Base in Lompoc, Musk had retweeted the SpaceX account with a link to its livestream.
But his early warning didn't stop people from wondering what the bright, oval shaped object that flew through the sky was around 5:30 p.m.
Falcon 9 and Iridium-4 went vertical last night on SLC-4E at Vandenberg AFB. Today's launch is at 5:27 p.m. PST. pic.twitter.com/ahwXNprr5Z— SpaceX (@SpaceX) December 22, 2017
SpaceX said this is the fourth flight for long-time customer Iridium. Both companies are under contract to launch a total of 75 satellites to provide communications services for regions around the world.