Astronomers suspect the asteroid has ejected its Geminid debris during one of its flybys of the Sun.
However, Dr Battams said the billions of tons of material in space cannot be accounted for by just solar activity.
He said: “Something catastrophic happened to Phaethon a couple of thousand years ago and created the Geminid Meteor shower.
“There’s no way the asteroid is anywhere near active enough when it is near the Sun to produce the mass of dust we are seeing, so we are confident that WISPR is seeing part of the Geminid meteor stream.”
Dr Battams added: “This is why NRL’s heliospheric imagers are so ground-breaking.