An ancient visitor has appeared from beyond the stars for the first time in over 50,000 years. It’s green — but it’s not an alien. Exactly.
Discovered in March of last year by California’s Zwicky Transient Facility, the long period comet C/2022 E3 (ZTF) formed eons ago within the distant Oort Cloud, a massive belt of interstellar objects that surrounds the entirety of our solar system.
Characterized by its bright green coma and tail, the interesting coloring that radiates from the distant comet’s core is caused by the sun’s reflection off its dominant component molecules, diatomic carbon and cyanogen. At the closest point of intersection between the comet’s orbit and ours, C/2022 E3 will come within 0.22 astronomical units of Earth, a relatively close fly-by in astronomical terms of about 20 million miles.
While our emerald-toned visitor is currently more than four times brighter than Haley’s Comet, it will still be a tough task to fully view it without telescopic assistance. The best viewing times will be just before sunrise or just after sunset when the sky is still dark, but the comet is illuminated by the sun. To the naked eye, the comet will appear at best as a bright, unusually fuzzy object in the night sky.
Although those of us in the greater Los Angeles area tend to be caught at a bit of a viewing disadvantage due to the massive amounts of light pollution and smog that plagues the city, there are a wide range of prime viewing spots just a close drive away. While natural conservation areas such as Joshua Tree National Park and the Angeles National Forest have great spots, a much closer option is to take a drive along Highway 1 past Malibu, where your personal telescope and potentially even your naked eyes have a much better chance at witnessing the full radiance of the passing comet. If you don’t have your own equipment or the chance to take an out-of-city drive, a group called The Virtual Telescope Project will be doing a free livestream of the comet every night on www.virtualtelescope.eu until its departure.