A comet not seen for tens of thousands of years is returning to the view of Earth.
C/2022 E3 (ZTF) is a long-period comet discovered by astronomers using the wide-field survey camera at the Zwicky Transient Facility in March 2022. Scientists say this is the first time the comet will be making an appearance in 50,000 years.
This means that prior to this most recent visit, the last time this comet appeared in Earth’s skies was during the Upper Paleolithic period, according to Space.com. Prehistoric humans would have spotted the comet in the depths of the last ice age.
This will also be the first comet visible in the sky since Comet NEOWISE put on a big show in 2020.
Scientists at NASA captured a telescopic image of the ZTF comet in December 2022 as it approached the inner solar system, noting the comet’s greenish coma, short broad dust tail, and long faint ion tail.
NASA expects the comet to reach perihelion, the point at which it is closest to the Sun, on January 12. It is expected to reach perigee, the point at which it is closest to Earth, between February 1 and 2.
The comet will be observable in the Northern Hemisphere in the morning sky moving toward the northwest in January. It will be just visible to the naked eye in dark night skies if it continues to brighten and will be easier to spot with binoculars and telescopes.
Long and short-form comets are two classifications of comets, determined based on their orbital period around the sun. Short-period comets have an orbital period of fewer than 200 years and long-period comets take over 200 years, with some taking 100,000 to 1 million years to orbit the Sun.
Comet Hyakutake — last seen in Earth’s skies in 1996 and not due back for another 70,000 years — was the closest passage by a comet in two centuries, at less than 10 million miles away from Earth.