The spectacular green-hued comet C/2022 E3 (ZTF) approached its closest distance to Earth on Wednesday, giving astrophotographers and stargazers around the world a once-in-a-lifetime sight.
The comet, which originated in the Oort Cloud at the far-flung reaches of our solar system, passed by Earth at a distance of around 26 million miles on February 1: for comparison, the moon is around 238,900 miles away from Earth. The comet is now on its way back out of the solar system on its extremely long orbit around the sun.
Photographers from across the globe have taken the opportunity to snap exciting pictures and videos of the comet and upload them to social media.
Photographer Dario Giannobile captured one amazing shot of the comet above Mount Etna in Italy, posting it to Twitter on January 27.
“A comet is like a dirty snowball,” Keith Horne, a professor of astronomy at the University of St. Andrews in Scotland, told Newsweek in January. “Comets and planets both orbit the sun, but unlike the circular orbits of planets, comets follow highly elliptical orbits.”
This comet in particular was first sighted by the Zwicky Transient Facility (ZTF) at the Palomar Observatory, near San Diego in California on March 2, 2022. Its characteristic green hue, which can be seen in many of the pictures, comes from the specific chemical make-up of the comet.
As comets approach the sun, the solar winds react with the chemicals inside their rocky and icy crust, causing the tail of debris characteristic to comets. In this comet in particular, there is diatomic carbon present, as well as cyanogen, which have caused the comet’s unique coloration.
“Under the effects of sunlight, both those substances glow green,” Gianluca Masi, an astrophysicist and astronomer with the Virtual Telescope Project of the Bellatrix Astronomical Observatory in Ceccano, Italy, told Newsweek in January.
“This is certainly a once-in-a-lifetime chance to see this object,” Chris Pattison, a senior research associate with the Institute of Cosmology and Gravitation at the University of Portsmouth in the U.K., told Newsweek last month.
“Any object this rare is interesting to see. It’s relatively rare for comets this bright to pass this close to Earth, and it’s even more interesting when they are a nice color.”
The comet will still be visible for a number of weeks, at first with the naked eye and using binoculars, after which a telescope will be needed because of the comet’s increasing distance from Earth.
“[It] will likely fade below naked eye visibility by the second week of February,” Robert Massey, deputy executive director of the U.K. Royal Astronomical Society, told Newsweek in January.
Stargazers can find it passing through the Camelopardalis in early February, after which it will cross into Auriga, and then into Taurus. Towards the end of February, it will pass the Orion constellation.
The February 5 full moon will impede the view of the comet, however, as the moon’s bright light will make it harder to spot its faint glow.
After its last hurrah, the comet will disappear from view, heading back out of the solar system. Astronomers predict that it may never return.
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