The mysterious light in the sky of the capital of Ukraine, Kyiv, gave rise to many assumptions. Officials in Kyiv said they suspected a NASA satellite had fallen to Earth, but the US space agency told the BBC it was still in orbit when the explosion occurred.

The Air Force of Ukraine suggested that the flash could have been a meteorite.

The Ukrainian defense is almost certain that the mysterious light was not caused by a Russian airstrike.

A bright light was seen in the metropolitan sky around 10:00 p.m.

The warning about the air raid worked, but “the anti-aircraft defense did not work,” Serhiy Popko, the head of the Kyiv military administration, reported on Telegram.

“According to preliminary information, this phenomenon occurred as a result of a NASA space satellite falling to Earth,” Popko said.

Earlier this week, the US space agency announced that the 300-kilogram satellite would re-enter the atmosphere on Wednesday.

The RHESSI satellite, used to monitor solar flares, was launched into low Earth orbit in 2002 and decommissioned in 2018, NASA said.

But NASA’s Rob Margetta told the BBC the satellite was still in orbit when the flare was spotted and would re-enter Earth’s atmosphere overnight.

NASA and the US Department of Defense continue to monitor the RHESSI satellite, he added.

Ukrainian social media was awash with theories and memes about what the outbreak could have been, with a popular topic being that it was caused by aliens.