Comet C/2022 E3 (ZTF), also known as the “Neanderthal Comet,” is approaching Earth and has already passed the limit of naked-eye visibility. This comet, which last returned to the Sun and Earth around 47,500 years ago, is now visible with small telescopes and conventional triaxes, and early observers have even reported seeing it without instruments. The comet has been visible all night since mid-January and is expected to reach its peak brightness in late January and early February. However, when it comes to naked-eye viewing, astronomers are tempering their expectations.

According to Martin Mašek of the Czech Astronomical Society, “It won’t be a very bright comet, like comet C/2020 F3 (NEOWISE) was in 2020,” but several experienced observers have reported seeing it with the naked eye under dark skies far from cities. The comet’s two tails, a long, ionized tail and a bright, dusty tail, can also be observed. The green color of the comet’s head is caused by sublimating cyanide in the comet’s head (coma).

Comet C/2022 E3 will pass through occultation (the closest point in its orbit to the Sun) on January 12, 2023 at a distance of 166.3 million kilometers from the Sun. It will be closest to Earth on February 1, 2023, coming within 42.5 million km of our planet. As it gets closer to Earth, its motion across the sky will accelerate, and it has already entered the circumpolar region of the sky, meaning it can be seen all night.

From February 2 onwards, the full moon will start to interfere strongly, making it difficult to observe the comet. However, it will be readily observable in trituration until the end of February and will be visible in small telescopes (with a diameter of 7 cm) until the end of March.

Comet C/2022 E3 may not be as bright as other comets we’ve seen in recent years, but it’s still an exciting opportunity for sky-gazers to observe a unique celestial phenomenon. As the comet approaches, it’s best to head to a location with minimal light pollution, and be sure to bring a telescope or binoculars for optimal viewing.

Article by Prague Forum