Update: Paul Lyman, resident astronomer at the Lick Observatory, says the trail of light was a meteor that was likely less than 1 centimeter in size.
The pull of gravity made the light streak occur.
SACRAMENTO -- It lit up the night sky Wednesday and it's still blowing up social media.
People up and down the West Coast witnessed and posted pictures of the unusual sight, appearing as an illuminated cloud. Some say the wispy trail was preceded by a flash.
To the eyes of Rick Therman, a custodian at Whitney High School in Rocklin, it looked like a rocket launch.
"It just shot off. Boom and there was the contrail," Therman said.
On Wednesday night, United Launch Alliance had hoped to launch the Delta IV Heavy rocket out of the Central Coast's Vandenberg Air Force Base. However, around 5:40 p.m., ULA reports the launch had been scrubbed and they will attempt it again Thursday night.
Launch Alert: we have declared a scrub for today's launch of the #DeltaIVHeavy. We will set up for a 24 hour recycle and the next launch attempt will be 12/20 at 5:31pm PST.
— ULA (@ulalaunch) December 20, 2018
Many in California are used to seeing strange bursts of light following SpaceX rocket launches but that does not appear to be the case this time.
So what was this?
A dashcam video posted by Richard Lopez captured the moment a ball of light streamed through the sky as he was sitting in his car at a Stockton intersection.
Vitaly Aristarkhov said he also saw the flash from Roseville and the object was falling. He said it looked like a meteor and he may be correct.
Experts say it was likely a meteor or space junk entering the atmosphere.
"We don't have any way of knowing which one it was," said National Weather Service Meteorologist Robert Ruehl. "Some people have questioned about the fact that it was like a crooked train behind it and that's just caused by the upper-level winds distorting it."
But why did it appear to have its own light?
"It's reflecting sunlight," Ruehl explained. "Even though the sun was below the horizon, it's still high enough up in the sky that the sun reflects off of it and that's what causes that."
Still not 100% certain, but evidence is growing the object seen was a meteor. A meteor can create a very high level cloud called a noctilucent cloud. @NASA has a great webpage explaining the cloud formation. https://t.co/eDquECamLl #cawx
— NWS Bay Area (@NWSBayArea) December 20, 2018
Whatever it was, Capt. Cameron Hillier of North American Aerospace Defense Command said there's nothing to worry about.
"With our radar, satellites and other centers that we have, this particular phenomenon doesn’t trigger any indications or warnings from our perspective," Hillier told FOX40. "So our operations center here at NORAD has made the determination that there’s no threat to the homeland at this point."
Want to see where the meteor was spotted? Check out the American Meteor Society's interactive map.
FOX40 viewers have been sending in dozens of photographs and videos. Feel free to send us yours!