Can comet Bernardinelli-Bernstein hit Earth? Monster rock hurtling towards solar system
Comets can be beautiful to watch with their sparkling tail whizzing past the sky. That being said, a new comet is now heading towards us, and will cross paths with us in the next 10 years. Known as Bernardinelli-Bernstein, the comet is at least 100 kms across, making it at least 1,000 times larger than most comets ever witnessed by humans.
Although headed towards our solar system, scientists believe that the Bernardinelli-Bernstein comet will not harm Earth. The comet will reportedly pass just outside the orbit of Saturn — a distance of 10.97 AU of the Sun. At present, the comet is travelling through the Oort cloud at about 29 AU.
The discoverers of the giant object — University of Pennsylvania astronomers Gary Bernstein and Pedro Bernardinelli — have confirmed their suspicions that we are dealing with a 'megacomet'. “The nearly spherical cow of comets,” they stated in the title of their paper, which they submitted for publication in The Astrophysical Journal Letters on September 23. The comet was assumed to be a dwarf planet in the beginning, travelling through the Oort cloud. It was later discovered that the rock is travelling through the Oort cloud extremely fast. Its glowing “coma”, that occur whenever a comet heats up, finally confirmed that it was a one and not a dwarf planet as it was previously assumed.
“The story told by the comet would tell us of what existed in the solar system billions of years ago, and we can use that to understand the things we see today elsewhere in the solar system,” Bernardinelli told The Daily Beast. This is not the first time this particular comet will pass our solar system. At a much farther distance of 18 AU, the Bernardinelli-Bernstein comet had whizzed past our solar system 3.5 billion years ago, following which it has travelled 40,000AU in the Oort cloud. To watch the comet from the earth, which is set to arrive in 2031, one has to use a telescope. "We conclude that BB is a 'new' comet in the sense that there is no evidence for [a] previous approach closer than 18 AU," said the researchers.
The comet was first discovered by the Dark Energy Survey project. In the project, which ran from August 2013 to January 2019, astronomers had mapped almost 300 million galaxies, in the process discoveing 800 unknown objects beyond the orbit of Neptune. The Bernardinelli-Bernstein comet was one of the objects discovered.