May 21 (UPI) -- A mysterious beam of light seen in the night sky over Arizona and neighboring states was likely caused by a Chinese rocket, an astronomer said.
The light sparked speculation online when it was spotted in the sky on the night of May 16, with some hypothesizing it could be energized particles in the atmosphere causing a space weather phenomenon known as Strong Thermal Emission Velocity Enhancement, or STEVE.
Other theories included reflections from ice crystals in the atmosphere, meteor activity or even extraterrestrial intervention.
Astronomer Tony Phillips wrote on spaceweather.com that the light was most likely caused by a Chinese rocket launched about an hour before the reported U.S. sightings. He said the beam of light may have been from the rocket falling our of orbit or from the deployment of its satellites.
"This plume was not an aurora, and it was not STEVE. We believe it is related to a rocket launch in China," Phillips wrote.
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