For the first time in 50,000 years, the public has the opportunity to witness a green comet as it passes by Earth.
The C/2022 E3 (ZTF) comet was first discovered in March 2022 by the Zwicky Transient Facility located at the Palomar Observatory in San Diego County, California.
When it was first noticed, the comet was 397 billion miles away.
It has traveled a bit since then. During the month of January, the green comet has been passing by the Earth, and it’s estimated to be closest to the planet on Feb. 1.
This will be the best opportunity to see the once-in-a-lifetime sight, but only with a little help.
“The brightness of the comet might just get to the very threshold of being visible in the sky,” said Jim Greenhouse, Space Science Director at the New Mexico Museum of Natural History & Science. “But probably not going to be all that obvious.”
The stars need to align – no pun intended – for the green comet to be seen. A viewer’s best shot is to find an open area with an untainted sky and will most likely need the assistance of binoculars or a telescope. Additionally, the weather also must cooperate.
Greenhouse explained that the bigger the comet, the brighter, and the green comet is predicted to reach a magnitude six, which is the highest number something can be in order to be visible in the sky under “ideal conditions.”
“Ideal conditions meaning you can’t have any light pollution, you can’t have any air pollution, you can’t have any clouds, anything. If you’ve got a perfectly dark, perfectly clear sky, you can see down to magnitude six,” he said.
Lastly, you need to know what you’re looking for. Greenhouse said that a green comet is green because “it contains an unusually high amount of carbon in it.”
“The infrared radiation from the sun starts to break the carbon down, and part of that process causes the emission of this dark green light,” he said. “The reason you only see the green in the head … is because the carbon pretty much gets broken down completely and turns into other elements by the time it reaches the tail.”
Greenhouse also noted that comets aren’t shooting stars, so a viewer shouldn’t be looking for a streak of light passing through the black sky. The green comet will be stationary and when viewed through binoculars or a telescope, it will be more like a fuzzy patch with an elongated side signifying where the tail is.
Now, you know what you’re looking for, but where in the vast night sky should you point your lens?
Greenhouse recommends checking online at skyandtelescope.org or using a star chart for the comet’s exact location when you’re attempting to view it, but it can be found in the circumpolar area of the sky, close to the North Star.
“There’s a certain area of the night sky between the North Star and the horizon that’s visible all night long, and the comet is going to be moving into that area of the sky,” Greenhouse said.
He added that leading up to the green comet’s closest pass of Earth, it will be between the Big and Little Dippers.
With the right tools, an open area and ideal weather conditions, you may be able to catch this once-in-a-lifetime sight.
