A newly discovered comet could be visible to the naked eye as it shoots past Earth and the Sun in the coming weeks for the first time in 50,000 years, astronomers have said.
The comet is called C/2022 E3 (ZTF) after the Zwicky Transient Facility, which first spotted it passing Jupiter in March last year.
After travelling from the icy reaches of our Solar System it will come closest to the Sun on Jan 12 and pass nearest to Earth on Feb 1. It will be easy to spot with a good pair of binoculars and likely even with the naked eye, provided the sky is not too illuminated by city lights or the Moon.
The comet “will be brightest when it is closest to the Earth”, Thomas Prince, a physics professor at the California Institute of Technology who works at the Zwicky Transient Facility, said.
Made of ice and dust and emitting a greenish aura, the comet is estimated to have a diameter of around a kilometre, said Nicolas Biver, an astrophysicist at the Paris Observatory.
That makes it significantly smaller than Neowise, the last comet visible with an unaided eye, which passed Earth in March 2020, and Hale-Bopp, which swept by in 1997 with a potentially life-ending diameter of around 60 kilometres.
But the newest visit will come closer to Earth, which “may make up for the fact that it is not very big”, Biver said. While the comet will be brightest as it passes Earth in early February, a fuller moon could make spotting it difficult.
For the Northern Hemisphere, Biver suggested the last week of January, when the comet passes between the Ursa Minor and Ursa Major constellations. The new moon during the weekend of Jan 21-22 offers a good chance for stargazers, he said.