A flash in the sky over the Ukrainian capital last night prompted confusion and alarm as city authorities said it was caused by a NASA satellite re-entering the atmosphere, but the US space agency denied involvement.
A "bright glow" was observed over Kyiv around 10pm (8pm Irish time), the head of Kyiv's military administration Sergiy Popko wrote on Telegram.
An air raid alert was activated, Mr Popko said, but "air defence was not in operation" in the besieged country fighting a Russian invasion.
"According to preliminary information, this phenomenon was the result of a NASA space satellite falling to Earth," Mr Popko said.
But a NASA spokesman denied this assessment, telling AFP that the satellite in question was "still in orbit".
The US space agency had announced this week that the retired 300kg Reuven Ramaty High Energy Solar Spectroscopic Imager spacecraft (RHESSI) would re-enter the atmosphere yesterday.
"However, that re-entry has not yet occurred -- RHESSI is still in orbit. NASA and the Department of Defense continue to track RHESSI. No other NASA satellite re-entered the atmosphere earlier today," a NASA spokesman told AFP.
The RHESSI spacecraft, used to observe solar flares, was launched into low Earth orbit in 2002 and decommissioned in 2018, NASA said.
The Ukrainian Air Force also said the flash was "related to the fall of a satellite/meteorite".
Speculation and memes abounded on Ukrainian social media after videos posted to several channels showed a powerful flash lighting up the sky over Kyiv.
"While social media is amused by flying saucer memes ... please do not use the official symbol of the Air Force to create memes!" the Ukrainian Air Force said.
In a statement on Monday, NASA said it expected most of the RHESSI spacecraft to burn up as it enters the atmosphere.
"But some components are expected to survive re-entry," NASA said, adding that the risk of harm to anyone on Earth was low, approximately one in 2,467.
