A comet twice the size of Everest flies to Earth: how dangerous is it

C/2017 K2 (PANSTARRS) is a non-periodic comet with a hyperbolic orbit. It was opened in May 2017, then it

was at a distance of 16.09 astronomical units from the Sun (2.4 billion km) beyond the orbit of Saturn.

Comet name PanSTARRS sounds familiar, and here's why. Pan-STARRS is a survey of the sky, its task is to find new asteroids, comets, supernovae and other celestial objects.

How big is Comet C/2017 K2?

It is currently unclear to experts howlarge comet nucleus. Initial observations from the Canada-France-Hawaii Telescope suggest a core between 30 and 160 km in diameter. But observations with the Hubble Space Telescope have shown that the core must be about 18 km.

Photo: Hubble, NASA

This means that it is large enough toscientists paid attention to it, but not as impressive as comets Hale-Bopp (60 km) and Bernardinelli-Bernstein (50 km). But don't write off C/2017 K2. If we compare it with terrestrial objects, then it is almost twice as large as Everest. The height of its peak Chomolungma is 8,848.86 m.

The size of a comet's tail, or coma, is also being actively discussed by astronomers. The trail of dust and gas behind C/2017 K2 is estimated to be somewhere between 130,000 and 800,000 km across.

Scientists believe that comets that aretoo far from the Sun, should not sublimate a huge amount of ice. This means that the activity of C/2017 K2 may be due to the mixing of ice with substances such as nitrogen, carbon dioxide, carbon monoxide and molecular oxygen.

Is the earth in danger?

Sadly the comet won't fit enoughclose enough to get a good look at the object. Even at closest approach, C/2017 K2 will still be further away from us than the average distance between Earth and Mars. But at least you can be calm - the planet is safe.

How to observe a comet?

The closest approach to the Earth will take place on July 142022. The problem is that a supermoon is expected on July 13 (this is the time when the moon is closest to the Earth and is fully lit at the same time). Perhaps there will be a strong illumination of the sky and it is worth trying to observe it now, while the sky is dark enough.

comet trajectory. A photo:
Tomruen, SS 4.0

C/2017 K2 is expected to fly byabout 270 million km from Earth. This is far enough away for the celestial object to be visible to the naked eye. But with a good telescope, you can see the comet, NASA officials said.

Astronomers estimate that comet C/2017 K2(PanSTARRS) has been moving out of the Oort cloud for about 3 Myr. This year, it first became visible with small telescopes in the Northern Hemisphere in May and will remain visible until September. Then it will become closer to the southwestern horizon and accessible to observers from the Southern Hemisphere.

What's next?

After flying by Earth in July, C/2017 K2 will continueyour way to perihelion. However, it is not known how it will behave as it approaches the star. Perhaps the object will become more active and bright, or fall apart and disappear completely, leaving behind only a dusty trail.

Read more:

Look at the celestial "Titanic" that will run on nuclear power

NASA figured out how to look for life on Mars: the experiment showed where it could be

Astronomers have found planets that are different from Earth, but suitable for life