COMET. On Wednesday, February 1, 2023, C/2022 E3 (ZTF) reaches its closest point to Earth. How to observe it? At what time ? With what tools? Our advices !

[Updated January 31, 2023 5:05 PM] Comet C/2022 E3 (ZTF) is about to reach its closest point to our planet Earth this Wednesday, February 1, 2023. A boon for all amateur astronomers who will be able to enjoy the spectacle observable with the naked eye or with binoculars at night. Composed of ice, gas and dust, the comet has a diameter of “about one kilometer”.

How to observe it? And, above all, how to recognize it? Comet C/2022 E3 (ZTF) looks like a small green dot in the sky and features a bright trail that reflects sunlight, providing an unforgettable sight from Earth. Of course, to observe this natural spectacle, it is still necessary that the sky is sufficiently clear and that you are in a place sufficiently protected from light pollution.

C/2022 E3 (ZTF) is a comet discovered in early March 2022 using a telescope camera at the Palomar Observatory in California. According to the calculations of astronomers, this is not the first time that it has approached the Earth, but to find its last visit, it is necessary to go back 50,000 years. At the time, Neanderthals may have seen it by looking at the sky…

C/2022 E3 (ZTF) is currently near the part of the solar system in which we are. After approaching the Sun on January 12, 2023, it will pass close to Earth on February 1. It will then be 42 million kilometers above our heads. Its magnitude at the time of this passage is estimated between 5.1 and 7.35. This will be the perfect time to admire it.

Comet C/2022 E3 (ZTF) moves across the sky night after night. Since January 28, she has reached the constellation of the Giraffe. It is at this location that you can observe it on February 1 when it is closest to Earth. After this date, C/2022 E3 (ZTF) will cross the constellation Coachman before approaching Mars on February 11 and 12. Using binoculars, it will then be possible to admire the two stars at the same time.

To locate the comet in the sky, you can use the Star Walk 2 and Sky Tonight smartphone apps. The Stelvision website also offers maps showing the path of the comet in the sky during the months of January and February.

Comet C/2022 E3 (ZTF) is closest to Earth on February 1, 2023, so it became visible throughout the night. It is high in the sky at sunset. From 3 a.m., it begins to descend toward the northwest horizon, but remains visible until dawn in areas where the horizon is clear.

Comet C/2022 E3 (ZTF) is highly visible through a telescope, having brightened since passing close to Earth. It is then possible to admire it with the naked eye in the night sky. To be sure not to miss anything of the show, equip yourself with binoculars or even a telescope.

You can also photograph a comet when it is visible to the naked eye with a simple camera with manual settings. You will be using a wide angle lens using fairly long exposures like 20 seconds and ISO 1600 (minimum 800). Attention, if the light pollution is important, it is advisable to lower the ISO. Think of composition, placing the comet above a building or a tree, or between two mountains. If you don’t have a tripod, use a self-timer to prevent the photo from being blurry when taken.

The next comet to pass close to Earth is therefore comet C/2022 E3 (ZTF) on February 1, 2023. It is currently observable in the Northern Hemisphere sky until February 1. The last passage of this comet near our planet was 50,000 years ago. It is therefore a spectacle not to be missed.

If you miss the rendezvous, know that it will take 50,000 years to see the celestial object again. At 20 Minutes, Léa Griton, lecturer at Sorbonne University and researcher at the Paris Observatory, explains that “in the solar system, objects are all subject to the enormous attraction of the Sun”. And if “the orbit of planets is almost round”, that of comets has “a very crushed ellipse”. After saying hello to the blue planet, C/2022 E3 (ZTF) will therefore return to the confines of our solar system.

Also in 2023, comet 103P Hartley could also pass Earth on October 13, 2023.

A comet is a celestial body made up of frozen gases, rocks and dust that originated from the formation of the solar system. These are real cosmic snowballs. So when this type of object passes close to the Sun, the latter heats the comet and melts the material. The comet then begins spitting out dust and gas in a gigantic glowing form, far larger than most planets. A comet’s size can vary from a few kilometers to tens of kilometers across when orbiting closest to the Sun. When its substances flow out, they form a spectacular cloud of gas and dust that trails behind it for millions of miles and that’s when it can be seen from Earth with the naked eye. .

Two tails form behind the comet. The first is made up of dust and is directly linked to the movement of the object. It is the most spectacular because it can measure several million kilometres. The second is made up of gas and is called the ionized tail.

Comets are formed from materials left over from the formation of the solar system. These objects are therefore witnesses to the formation of the solar system. “This material has not evolved, it has been kept intact, as if it had been placed in the freezer, and it is therefore the witness of these first moments.” said astrophysicist Françis Rocart, head of the Rosetta program in an article in Le Monde in 2014.

A comet’s nucleus is made up of frozen gases in the form of ice, rocks, and rock dust. Studies of Comet Tchouri indicate that it is also covered in carbon and have also spotted many organic molecules that had never been identified anywhere other than on Earth. Thus, it could be that the elements that allowed life to appear on our planet came from space and were brought in by an intensive bombardment 4 billion years ago. To find out more, we would have to study the composition of many other comets…