Western U.S. Saw An Amazing Light Show Last Night, Courtesy Of China

Maybe it was a meteor? Or space junk? People on the West Coast weren't sure what the bright object was that streaked across the sky Wednesday night, but they knew it was spectacular. Now comes word that the object — which separated into bright fragments — was a stage of China's large new rocket.

Americans who spotted the flaring object Wednesday night could be forgiven for not knowing that. "Oh my gosh!" was a common reaction, as in a video taken in Utah by Matt Holt.

The light show appeared in skies over the western U.S. around 9:30 p.m. PT, sparking a flood of reports to meteor-monitoring groups, a flurry of tweets and a number of striking videos. While first-person accounts on Meteorite News differed, some details were constant: The string of objects moved from west to east, with alternating colors and a bright trail.

We got in touch with Holt to ask him about his experience — and whether he, like others in his video, was worried by what he saw.

"I was not concerned at all; just in awe at the science of space," he says. Noting the reports that the object has since been identified as a large Chinese rocket booster re-entering Earth's atmosphere, Holt adds, "I think a world-ending light show would be, um, over a lot quicker."

"What the hell is it?" is how another video starts — one that, we warn you, also includes some profanity. Taken by Ian Norman in an open area in Alabama Hills, Calif., near the Sierra Nevada mountains, the video shows the object streaking across the sky and over the horizon, in a scene that lasts for well over a minute.

The object was the second stage of China's Chang Zheng 7 rocket that was launched on June 25, according to astronomer Jonathan McDowell of the Harvard-Smithsonian Center for Astrophysics, who cites confirmation from the Space-Track organization and the Joint Space Operations Center.

This was the first CZ-7 launched, McDowell says, adding that it's rare for objects of more than 5 tons to re-enter Earth's atmosphere.

A spokesman for U.S. Strategic Command confirmed the re-entry, saying that its Joint Space Operations Center, which tracks objects that orbit our planet, "removed a Chinese rocket body, a CZ-7 rocket body, from our U. S. satellite catalog as a 'decayed object' last evening."

As McDowell tells NPR's Nell Greenfieldboyce, "The only bigger event this year was a Russian rocket stage that re-entered over Vietnam on New Year's Day."

"It's pretty. You can immediately tell that it's probably space junk. It lasts longer, moves slower than a natural meteor or fireball, and it has this characteristic sort of shedding material," he says. "Because what's happening of course is that you're dropping a several ton hunk of aluminum into the atmosphere at 18,000 miles an hour and parts of it melt and then you get several separate chunks falling through the sky."

McDowell also tells Nell that while the risk of anyone being struck by objects falling to Earth's surface is very low, many engineers and designers make sure that a re-entry takes place over an ocean or another safe place.

Discussing China's space program, McDowell says, "It's a bit surprising that their new, fancy modernized launch system didn't include the ability to safely dispose of the upper stage."

At the Joint Space Operations Center, Air Force Capt. Nicholas Mercurio tells Nell that the rocket section was more than 30 feet long, and that it had been tracked for the past month. In 2015, Mercurio says, there were 110 re-entries of tracked objects — his agency keeps track of those objects that are 10 cm or larger.

People had time to stare at the fragmented object as it sparkled in the sky — reportedly as bright as the moon or any star — and also to record the scene, because it persisted for at least 20 seconds, and in some cases for much longer, according to observers who sent a record of their impressions to the American Meteor Society.

The society says it received 47 reports about the fragmented object, from as far north as Montague, Calif., as far east as Salt Lake City, and as far south as San Diego. Sightings were also reported in Las Vegas and in Big Bear, Calif.

One TV reporter who happened to snag footage of the spectacle had the same reaction, saying as the bright fragments trailed across the dark sky, "Holy... no way!"

That's the impression of Nicole Vowell of KSL 5 TV, who then added, "I don't know, that's pretty much the sweetest thing I've ever seen in my life."