A mega-comet has just passed safely through Earth, but there is still the possibility that it will grow brighter during the summer as it approaches the sun in December.
Comet C / 2017 K2 (PANSTARRS), abbreviated K2, made its closest approach to our planet on Thursday (July 14). It passed 168 million miles (270 million kilometers) from Earth (beyond the orbit of Mars).
This distant approach meant that K2 had a somewhat dim vision, despite its large size. The megacomet was first detected in 2017 by the Panoramic Survey Telescope and Rapid Response System (PanSTARRS) at the outer ends of the solar system.
But there are more things to come, as K2 now continues its journey into the sun and will make its closest approach to the star around which it orbits, the so-called perihelion, in December. The comet, which is visible these days by large amateur telescopes, can light up in the warmer environment closest to the sun and move to the middle binocular range if we are lucky.
Related: The strange and massive comet K2 is traversing the solar system, surprising scientists as it happens
Early observations of the comet revealed a potentially large nucleus (or nucleus) and a huge envelope of gas and dust. At that time, the comet was located between the orbits of Saturn and Uranus, about 2.4 billion km (1.4 billion miles) from the sun, which is about 16 times farther than the Earth from the sun. The fact that K2 already had a gaseous coma surprised scientists, as in the depths of the solar system, temperatures are so cold that comets, mostly made of water ice, are supposed to be as still and dead as the comets. rocks.
Scientists are still debating the size of the comet. The Canada-France-Hawaii Telescope (CFHT) suggested that the K2 core could be 18 to 100 miles (30 to 160 km) wide, but data from the Hubble Space Telescope showed it could be only 11 miles ( 18 km) wide.
Comet activity is always difficult to predict, as we cannot say exactly how the sun’s heat will affect K2 or whether it will survive the passage. Now located at a magnitude of about 7 or 8, the comet should remain visible in telescopes at least for the rest of the summer. Visibility to the naked eye is magnitude 6, by comparison.
The perihelion will occur on December 19 and so far, the comet has become brighter as it moves toward the inner solar system. So we can only hope that in the coming weeks, the comet will become a little brighter so that more people can see it beyond the images coming from larger observatories.
The perihelion will also be far away, as K2 will be about 1.8 astronomical units from the sun (almost twice the distance between the Earth and the sun) as it gets closer.
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