- A rare green comet flies past Earth in late January and early February.
- Comet ZTF has not passed our planet since the last ice age, and humans may never see it again.
- These stunning photos show what you might see when spotting the green comet in the night sky.
A rare green comet is sweeping past Earth, and this could be humanity’s last chance to see it. Stunning photos are already revealing what you might see as you gaze up at the pre-dawn sky and spot the ball of frozen gas and dust darting past.
The comet’s formal name is C/2022 E3 (ZTF), named after the Zwicky Transient Facility, which first discovered it in March. But skywatchers call it Comet ZTF for short.
This icy cosmic passerby paints a green streak across the sky until the early days of February. You’ll probably need binoculars or even a telescope to see it far from city lights under dark skies.
If you catch Comet ZTF with a telescope you might see something like this:
Many comets shine green like that. Laboratory research has linked this aura to a reactive molecule called dicarbon, which emits green light when sunlight breaks it down.
Although green comets occasionally pass Earth, this one will not return for about 50,000 years, if at all. That’s how long it takes for comet ZTF to orbit the sun, meaning Neanderthals were still walking the earth when it last whizzed by during the last ice age.
“We enjoy seeing and photographing the comet because bright comets are not only rare but also as beautiful as this one. Comet tails are never the same,” Chris Schur, an amateur astronomer and night sky photographer in Arizona, told Insider in an email. “[Comets] Move among the stars from night to night, sometimes making just finding them a challenge.
Astronomer Gianluca Masi captured the footage below Comet ZTF, with its moving background stars, during a live broadcast of his telescopic observations:
“Watching such an ‘icy world’ is always very fascinating,” Masi told Insider via email. “The beauty of Comet C/2022 E3 ZTF reminds us that these objects are the most elegant ones up there and we simply cannot pass up the opportunity to take a look.”
Would you like to see the green comet for yourself? Head to a place with dark skies, away from city lights, and look up at Polaris, the North Star, before dawn. Use a telescope if you can, or at least bring binoculars. Unless you’re under a very, very dark sky, the comet probably won’t be visible to the naked eye.
The comet is making its way past the constellations Boötes and Hercules, according to EarthSky.org. Closer to January 30th, the green space snowball will appear near Polaris and earlier in the evening.