Earth to be visited by once-in-50,000-year comet

By Georgina Torbet Published January 8, 2023

Skywatchers will soon be in for a special treat, as a comet which passes our planet just once every 50,000 years should be visible in the skies this month. Comet C/2022 E3 ZTF will be making its closest approach to Earth in the next few weeks, and may even be visible to the naked eye.

The comet was discovered in March 2022 at the Zwicky Transient Facility, hence the ZTF in its name, when it was almost 400 million miles from the sun. Unlike asteroids, which are made of rock, comets are made primarily of ice, and as they approach the sun and get hotter this ice melts and lets off gasses. This is the process that forms the distinctive tails of comets. Long-period comets like this one have highly eccentric orbits and are thought to originate from the Oort cloud, a very distant cloud of icy bodies which orbit around the sun far beyond the orbits of the plants and the Kuiper belt.

Comet NEOWISE. — An unprocessed image from the WISPR instrument onboard NASA’s Parker Solar Probe shows comet NEOWISE on July 5, 2020, shortly after its closest approach to the Sun. The Sun is out of frame to the left. The faint grid pattern near the center of the image is an artifact of the way the image is created. The small black structure near the lower left of the image is caused by a grain of dust resting on the imager’s lens. NASA/Johns Hopkins APL/Naval Research Lab/Parker Solar Probe/Brendan Gallagher

Comet C/2022 E3 ZTF will be bright enough that it should be visible to the naked eye; the first such comet since NEOWISE passed by the Earth in 2020. NEOWISE gave spectacular views as it came close to the planet, however, according to Sky at Night magazine, the comet visible this month won’t be as bright as that one and will likely look more “like a smudge in the sky.”

Recommended Videos

To get the best view of C/2022 E3 ZTF, skywatchers will need binoculars or a telescope, and the best time to look for it will be in late January and early February. The comet makes its closest approach to the sun on January 12, and its closest approach to Earth on February 1. The Planetary Society advises those in the Northern hemisphere to look in the northwestern skies for a faint, greenish smudge.

Alternatively, if you’d rather watch from home, the Virtual Telescope Project will be livestreaming the comet’s close approach on January 13.

Topics

Tech News

Georgina Torbet

Space Writer

Georgina has been the space writer at Digital Trends space writer for six years, covering human space exploration, planetary…

Space

James Webb investigates mystery of where Earth’s water comes from

This illustration of Comet 238P/Read shows the main belt comet sublimating—its water ice vaporizing as its orbit approaches the Sun. This is significant, as the sublimation is what distinguishes comets from asteroids, creating their distinctive tail and hazy halo, or coma. It is especially important for Comet Read, as it is one of 16 identified main belt comets found in the asteroid belt, as opposed to the colder Kuiper Belt or Oort Cloud, more distant from the Sun. Comet Read was one of three comets used to define the class of main belt comets in 2006.

As wild as it might sound, scientists have a theory that water on Earth didn't actually originate here: the first water may have been brought to our planet by a comet. To understand whether that is the case, astronomers look to the comets commonly found in the asteroid belt between Mars and Jupiter, and recent research using the James Webb Space Telescope has identified a clue in this long-standing mystery.

Researchers used Webb's Near-Infrared Spectrograph instrument to look at the composition of a comet in the asteroid belt, and they found evidence of water vapor around a comet in this area for the first time. Looking at Comet 238P/Read showed nearby vapor, supporting the idea that water could be carried by such a comet. While many comets come from more distant locations like the far-off Oort cloud, which is a long way from the sun where it is easier for water ice to survive, this particular comet hangs out in the main asteroid belt.

Space

Unique black hole is trailed by 200,000 light-year-long tail of stars

This is an artist's impression of a runaway supermassive black hole that was ejected from its host galaxy as a result of a tussle between it and two other black holes. As the black hole plows through intergalactic space it compresses tenuous gas in front to it. This precipitates the birth of hot blue stars. This illustration is based on Hubble Space Telescope observations of a 200,000-light-year-long contrail of stars behind an escaping black hole.

Black holes might have a reputation as terrifying monsters, devouring all they come into contact with -- but they can be a force of creation too, feeding the formation of new stars. Researchers using data from the Hubble Space Telescope recently spotted an unexpectedly huge trail of stars forming in the wake of a rogue black hole.

While most very large black holes, called supermassive black holes, sit at the center of galaxies, occasionally these enormous beasts can be found wandering alone in the depths of space. That's the case with the recently discovered black hole with the mass of 20 million suns, which is streaking through the sky at tremendous speed. This likely began with two galaxies merging, each with its own supermassive black hole, which formed a binary system. Then a third galaxy got too close, and in the chaos of a three-way merger one of the black holes was kicked out and sent zipping off into space -- so fast that if it were in our solar system, it would travel from the Earth to the moon in 14 minutes.

Space

We now know what caused comet ‘Oumuamua’s strange orbit

An artist’s depiction of the interstellar comet ‘Oumuamua, as it warmed up in its approach to the sun and outgassed hydrogen (white mist), which slightly altered its orbit. The comet, which is most likely pancake-shaped, is the first known object other than dust grains to visit our solar system from another star.

Remember what feels like decades ago, when we were visited by a comet from another solar system in 2019? Interstellar comet ‘Oumuamua captured headlines when its cigar-shaped body was spotted following an unusual orbit through our solar system, and subsequent research suggested it might once have been part of a Pluto-like planet and was possibly pancake-shaped.

One thing particularly puzzled astronomers, though, because the comet was accelerating away from the sun in a path that seemed strange. Now, researchers say they have an explanation for its unusual pathway, and it isn't aliens -- it's a natural phenomenon called outgassing.