Earth’s night sky is getting a surprise visitor this month.
Comet C/2022 E3 ZTF will be the closest approach to both Earth and the Sun in the coming weeks. The comet was first spotted in March 2022 by astronomers at the Zwicky Transient Facility, part of the California Institute of Technology’s Palomar Observatory, when it was 399 million miles (643 million kilometers) from the Sun, just inside Jupiter’s orbit. Since then, Comet C/2022 E3 ZTF has moved much closer to the Sun and Earth.
Actually, at 23:00 EST on January 12 (0400 GMT on January 13)the comet’s closest approach to the sun, known as perihelion. During this time, skygazers may be able to spot the comet with the naked eye, but if conditions are right you should be able to find it with binoculars or a telescope. Even if you don’t have the right conditions or optics to spot C/2022 E3 ZTF, you can watch a free live webcast courtesy of the Virtual Telescope Project website (opens in new tab) or his Youtube channel (opens in new tab).
Related: Watch online next week as a comet makes its closest approach in 50,000 years
Comet C/2022 E3 ZTF has an orbital period of 50,000 years, which means it has not approached Earth since the Upper Paleolithic, the time of the Early Period homo sapiens and the Neanderthals.
Not only has the comet not visited us in quite some time, this could also be the last time we see it. Its orbit is not closed, meaning it will not return to the same angular position it started at. Due to its highly parabolic orbit, C/2022 E3 ZTF will zoom back out into space after its closest approach to Earth – perhaps never to return. Jessica Lee, astronomer at the Royal Observatory Greenwich, told Newsweek (opens in new tab) that “Projections indicate that the orbit of this comet is so eccentric that it is no longer in orbit – so it will not return at all and will just keep going.”
Several astrophotographers around the world have captured beautiful images of the comet as it races through the solar system. Its coma, the cloud of gases and debris surrounding the comet’s nucleus, is a distinctive green color in photos due to its chemical composition. The green color indicates the presence of diatomic carbon or dicarbons, molecules with two carbon atoms bonded together.
Comet C/2022 E3 ZTF should be visible throughout the month, not just on January 12 at perihelion. After this close approach to the Sun, the comet will pass within 42 million km (26 million miles) of Earth on February 2nd.
The Comet C/2022 E3 ZTF offers an excellent sky viewing opportunity for skywatchers of all experience levels. If you don’t have the gear you need (or want!), be sure to check out our guides to the best binoculars and the best telescopes to see the comet or other interesting objects in the sky. To capture the best possible comet images, we have recommendations for the best cameras for astrophotography and the best lenses for astrophotography.
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