Newly-discovered Comet ZTF is coming the closest to the Sun in 50,000 years, becoming visible to the naked eye, and making big headlines. Some are calling it a “super rare” and “bright green” comet, but will it live up to the hype? We explain.
Comet ZTF Facts
Comet ZTF was discovered on March 2, 2022 by a robotic camera attached to a telescope known as Zwicky Transient Facility (ZTF) at the Palomar Observatory in Southern California. ZTF scans the entire northern sky every two days and captures hundreds of thousands of stars and galaxies in a single shot. Many comets have been found with this instrument. The most recent is catalogued as C/2022 E3 (ZTF), Comet ZTF for short.
Why Is It Rare?
Comet ZTF has travelled a distance of 2.8 trillion miles and will make its closest approach to the Sun in 50,000 years on February 1, 2023. Orbital computations suggest that Comet ZTF may never return again.
What Makes ZTF A Green Comet?
The greenish color is likely due to a molecule made from two carbon atoms bonded together, called dicarbon. This unusual chemical process is confined chiefly to the head, not the tail. If you get a look at Comet ZTF, that greenish hue is likely to be quite faint (if it is visible at all). The appearance of green comets due to dicarbon is fairly uncommon.
Recent images show the head (coma) appearing to be distinctly green and trailed by an impressively long thin blush appendage (the tail). But that is what a camera taking a long exposure sees. The tint will look much less green to the naked eye.
When and where to see Comet ZTF
During the latter part of January into early February, Comet ZTF may become bright enough to be glimpsed with the naked eye. Use a reliable star map to track the night-by-night change in position relative to the background stars and constellations. Here are dates and approximate locations.
Look towards constellation Corona Borealis before sunrise.
Look towards constellation Boötes before sunrise.
Look above the horizon any time throughout the night.
Look several degrees to the east of the bowl of the Little Dipper. On the evening of the 27th, it will be about three degrees to the upper right of orange Kochab, the brightest of the two outer stars in the Little Dipper’s bowl.
Look near the constellation Camelopardalis.
Look towards the brilliant yellow-white star Capella (of the constellation Gemini).
Look within the triangle known as “The Kids” star pattern in Auriga, directly overhead at around 8 p.m. local time.
Look two degrees to the upper left of Mars.
Note: If you live in a big city or an outlying suburb, sighting this comet is going to be a difficult—if not an impossible task. Even for those who are blessed with dark and starry skies, finding ZTF could be a bit of a challenge.
Watch Comet ZTF live now:
More Information About Viewing ZTF
As for the tail, comets can shed two types, composed of dust and gas. Dust tails are far brighter and more spectacular to the eye than gas tails, because dust is a very effective reflector of Sunlight. The most spectacular comets are dusty and can produce long, bright tails making them awesome and impressive celestial spectacles.
Gas tails on the other hand appear much fainter and glow with a bluish hue. The gas is activated by the ultraviolet rays of the Sun, making the tail glow in much the same way that black light causes phosphorescent paint to light up. Unfortunately, gas tails produced by most comets, appear long,…
Read More: How To See The New “Green” Comet