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Green Comet C/2022 E3 (ZTF) Passes Over Earth This Week

Green Comet C/2022 E3 (ZTF) Passes Over Earth This Week

The James Webb Space Telescope will be tracking it, hoping to gain clues about the formation of the Solar System.

Last month, I noted that excitement was building as a green comet, designated C/2022 E3 (ZTF), would be seen in our skies for the first time since Neanderthals roamed the Earth.

It’s now at its closest approach to our planet, and sky-watching enthusiasts are keen to get a glimpse. Here is how to see it:

According to In-the-Sky,  from New York City C/2022 E3 (ZTF) is circumpolar, meaning it is permanently above the horizon, and should therefore be visible for most of the night. It will be visible in the Camelopardalis constellation while at perigee, a large but faint area of sky devoid of bright stars and located close to the north celestial pole.

The comet will become visible at around 6:49 p.m. EST (2349 GMT) on Wednesday (Feb. 1) when it will be 49 degrees over the northern horizon. C/2022 E3 (ZTF) will climb to its highest point in the sky, 58 degrees over the northern horizon, at around 9:46 p.m. EST (0246 GMT). Following this it will disappear in the dawn light at around 5:57 a.m. EST (1057 GMT) on Feb. 2 while at around 30 degrees over the horizon to the north.

The comet will remain visible through early February, and will finally become visible to observers in the southern horizon this month. C/2022 E3 (ZTF) may be visible to the naked eye but should be easier to spot with binoculars or a telescope. The easiest times to spot it may be on Sunday (Feb. 5) when the comet is next to the bright star Capella in the Auriga constellation, or between Feb. 9 and Feb. 13 when it will shine near Mars in the Taurus constellation.

The distinctive green color comes from the breakdown of carbon compounds within the comet.

The green color can be explained by the presence of certain compounds in the coma—primarily, diatomic carbon but also cyanogen [C2N2, a carbon-nitrogen compound].

“Under the effects of sunlight, both those substances glow green,” Gianluca Masi, an astronomer with the Virtual Telescope Project—a service provided by the Bellatrix Astronomical Observatory in Ceccano, Italy that operates and provides access to robotic, remotely operated telescopes—told Newsweek.

Sunlight breaks down the diatomic carbon molecules into single carbon atoms before they can move into the comet’s tail. This is why the green color is limited to the region surrounding the icy nucleus of the comet. The object’s vast dust tail, in contrast, appears to be white.

One can only hope the eco-activists don’t start shrieking “climate crisis” in light of the comet’s carbon emissions.

NASA is planning to track the comet with the James Webb Space Telescope.

NASA plans to observe the comet with its James Webb Space Telescope (JWST), which could provide clues about the solar system’s formation.

“We’re going to be looking for the fingerprints of given molecules that we can’t access from the ground,” said planetary scientist Stefanie Milam of NASA’s Goddard Space Flight Center in Maryland. “Because JWST’s so sensitive, we’re expecting new discoveries.”


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I prefer Barkeeper’s friend… 🙂

Is this the one that turns mankind into zombies? I hate when that happens.

Hey, Neanderthals are still roaming the earth.

    They insure their cars with GEICO. It’s so simple even a cave man can do it. And they vote with mail in ballots—but that’s not so simple, they usually have to have someone else has to fill them out for them.

hoping to gain clues about the formation of the Solar System
They’re going to be disappointed.
Especially since it’s really a Formic ship.

BierceAmbrose | February 1, 2023 at 3:02 pm

It’s not a green comet. It’s color-fluid

I’ve been tracking this bad boy for over a week with my scope, as it has been threading its way up the path between the North Star and the dipper pointer Dubhe, but it’s been a huge disappointment. After recalibrating several times and finding nothing at the proper coordinates, I realized that I was indeed seeing the faintest of green fogs, but so faint that it could have been my imagination or a hallucination. Absolutely no definition at all, never mind a tail (never mind two tails, as there was even supposed to be a white anti-tail). I intend to try one more time tonight if it’s clear (it’s been cloudy and raining the past two nights) and show it to our fifth-grader if there’s anything worthwhile to see.

This has been incredibly disappointing compared to the bright and well-defined NEOWISE two years ago, and the one before that that was viewable through common binoculars. This one has not lived up to its hype: “Christmas comet,” “naked eye sighting,” and all that.

    henrybowman in reply to henrybowman. | February 1, 2023 at 10:05 pm

    Nah, still an amorphous and disappointing green fuzzball. We both got to see it, and we were both unimpressed. (Note that the photo up top is a 40-second exposure, so eyeball viewing is proportionally dissatisfactory.)

    But I showed him some nice views of the moon and Jupiter (with three clear moons), so I salvaged my grampa points for tonight.

    Anyone who is curious to get notifications of interesting sky spectacles, such as comets, meteor storms, and the like, can subscribe to Spaceweather Alerts. Many of their alerts concern auroras, lightning sprites, and colorful noctilucent clouds that never show up at my low latitude, but if you’re up north you may enjoy those as well. Their current front page (dated 2/2) has some very nice comet coverage and photos, including a finder chart.