Keen star-gazers in London last night (1 February) may have been lucky enough to spot a rare green comet, that was last seen 50,000 years ago.
According to NASA, the comet glows green due to carbon gas, and would've last been around when woolly mammoths still were.
Named C/2022 E3, the rock is also made with ice, and leaves a dust trail as it goes.
It's thought it'll get even closer to Earth today (2 February).
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