It's probable that the impact object comes from a Chinese rocket launched in 2014. //

It was engineer Jon Giorgini at NASA's Jet Propulsion Laboratory who realized this object was not, in fact, the upper stage of a Falcon 9 rocket. He wrote to Gray on Saturday morning explaining that the DSCOVR spacecraft's trajectory did not go particularly close to the Moon. The second stage would, therefore, be extremely unlikely to strike the Moon. This prompted Gray to dig back into his data and identify other potential candidates.

He soon found one: the Chinese Chang'e 5-T1 mission launched in October 2014 on a Long March 3C rocket. This lunar mission sent a small spacecraft to the Moon as a precursor test for an eventual lunar-sample return mission. The launch time and lunar trajectory are almost an exact match for the orbit of the object that will hit the Moon in March.

"In a sense, this remains 'circumstantial' evidence," Gray wrote. "But I would regard it as fairly convincing evidence. So I am persuaded that the object about to hit the moon on 2022 Mar 4 at 12:25 UTC is actually the Chang'e 5-T1 rocket stage."