Videos of the surprising sight were posted to social media by witnesses on Friday night, including from revellers at the King Kong Brewing Company in Sacramento.
“Mainly, we were in shock, but amazed that we got to witness it,” Jaime Hernandez told the Associated Press. “None of us had ever seen anything like it.”
The lights were also seen as far north as Oregon before fizzling out.
Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics, explained that the lights were in fact space junk burning up as it reentered the Earth’s atmosphere.
Mr McDowell took to Twitter to explain that the debris was in fact an ICS-EF, or an Inter-orbit Communications System - Exposed Facility, Japanese communications package.
It had been used to send data between the ISS Kibo module and Mission Control Tsukuba via the Kodama data relay satellite.
Mr McDowell tweeted that the equipment was launched to the International Space Station by Space Shuttle in 2009.
And it became space junk in 2020, orbiting the Earth for three years before reentering the Earth’s atmosphere over California at 9.30pm on Friday.