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The largest comet ever observed is heading towards the solar system, according to a NASA statement.
But the Bernardinelli-Bernstein comet, with its 85-mile diameter making it longer than the emirate of Dubai, is not expected to come any closer than one billion miles away from the sun, roughly the same distance as Saturn.
The behemoth comet traveling at 22,000 miles per hour is due to come closest to the center of the solar system in 2031.
It has an estimated mass of around 500 trillion tons, around one hundred thousand times larger than the mass of a typical comet found closer to the sun.
The previous record holder was the C/2002 VQ94 comet, with an estimated size of 60 miles across. It was spotted in 2002.
Bernardinelli-Bernstein is currently two billion miles away from Earth.
Scientists estimated the mass of the comet’s nucleus by measuring its reflectivity.
The center of the comet, believed to be as black as charcoal, is obscured by a large cloud of dust and debris.
NASA astronomers believe that the Bernardinelli-Bernstein comet came from the hypothesized Oort Cloud on the outer edges of the solar system.
This cloud is believed to be a “nesting ground” for comets that fall towards the center of the solar system when disturbed by the gravitational pull of passing stars – a process that NASA likened to shaking apples out of a tree.
Bernardinelli-Bernstein is believed to have been falling towards the sun for well over a million years.
It follows an elliptical orbit that takes three million years to complete.
“This comet is literally the tip of the iceberg for many thousands of comets that are too faint to see in the more distant parts of the solar system,” said David Jewitt, a professor of planetary science and astronomy at the University of California, Los Angeles (UCLA), and co-author of the new study in The Astrophysical Journal Letters.
“We’ve always suspected this comet had to be big because it is so bright at such a large distance. Now we confirm it is.”
Source: Alarabiya
