Occasionally, the skies above the Earth are graced by the presence of a comet. Comets are celestial objects composed mostly of ice and dust. Comets orbit the sun in vast elliptical orbits that can carry them from the far outer regions of the solar system to the regions near the sun. Comets come in two different types defined by the length of their orbit. There are short-period comets, which generally orbit the sun once every hundred years or so. The other type are long-period comets, which generally take thousands of years to orbit the sun. Every once in a while, a comet passes through the inner solar system and can be seen from the surface of Earth. In late January to early February, those living in the Northern Hemisphere may be lucky enough to see a newly discovered comet that hasn’t been this close to Earth in 50,000-years.
A Newly Found Comet
The comet, which has been designated C/2022 E3 (ZTF), was discovered last March as it passed by Jupiter. On January 12, the comet will make its closest approach to the sun, and on February 1, it will make its closest approach to the Earth. However, the comet will actually be most visible a week before its closest approach, as the week of its closest approach may be overshadowed by a bright moon as the next full moon will be on February 6. However, there will be a new moon on January 21, which may offer the best chance for viewing the comet. If you happen to live in an area with little to no light pollution, you may even be able to see the comet with just your eyes. If there is a lot of light pollution, you will still be able to view the comet with binoculars or a small telescope.
Where Did The Comet Come From?
Comets are believed to originate in the far out regions of the solar system in an area called the Oort Cloud. The Oort Cloud is a vast sphere of comets that encircle the solar system, and its existence is inferred by the presence of long-period comets. C/2022 E3 (ZTF) last visited the inner solar system around 50,000-years ago, and so it likely originated in the Oort Cloud as well. As the comet approaches the sun, solar heating will melt some of the ice on the comet’s surface and create a vast tail of material. In the case of C/2022 E3 (ZTF), its tail will appear greenish.
Past and Future Encounters
C/2022 E3 (ZTF) last passed by the Earth some 50,000-years ago, a time long before humans even started the first civilizations. The last time C/2022 E3 (ZTF) was visible from Earth, Neanderthals still existed and the Earth was locked in an ice age. After its current approach, astronomers estimate that it will be another 50,000-years before it is visible again, making this comet a truly once in a lifetime event. Knowing how much has changed in the last 50,000-years, it makes one wonder what will be different the next time the comet approaches. However, there is also a possibility that the comet could be ejected from the solar system entirely, and astronomers will be closely studying the comet’s path to determine its future.