Comet C/2022 E3 ZTF is one of the best examples of astronomers being bad at naming things, and is a long-period comet discovered in 2022 by the Zwicky Transient Facility. Although not obvious in this monochrome GIF, the comet has a green color, due to sunlight interacting with the molecules in it’s coma, specifically with diatomic carbon (C2) and cyanogen [(CN)2].
The comet reached its closest point to the sun (perihelion) on January 12th, and will reach its closest point to Earth on February 1st, when it’s expected to be faintly visible to the naked eye. The comet has a short dust tail, and a long but faint ion tail that’s just barely visible in this GIF, which shows the comet’s motion over 45 minutes. The comet also developed an antitail which points towards the sun on January 22nd, which was caused by particles in the same orbital plane as the comet being aligned with Earth, making it look like the comet has 2 opposite tails.
The comet was last near earth over 50,000 years ago, but isn’t going to return in anywhere near that short of a time. Calculations from it’s orbit show that it will either take millions of years to come back again, or leave the solar system entirely, never to return.
JML Astrophotos 