The Bernardinelli-Bernstein Megacomet is over 80 miles wide — and it’s headed our way

Last year, the giant comet Bernardinelli-Bernstein (also known as C/2014 UN271) was discovered by University of Pennsylvania astronomers of the same name Gary Bernstein and Pedro Bernardinelli. The pair called it the “nearly spherical cow of the comet” in their paper about the discovery, but it wasn’t long before the world called it the “megacomet” because it was an absolute unit of a space object.

While the megacomet fell out of the main space news focus, NASA astronomers have been setting the Hubble Space Telescope’s sights on the object for several months since — and discovered it really is. how big. A new article was published in The Astrophysical Journal Letters confirmed Tuesday that Bernardinelli-Bernstein has a nucleus – the icy core at the center of all comets – more than 80 miles wide. It is nearly 50 times larger than other comets and is the largest comet ever observed.

“This comet is really the tip of the iceberg for thousands of comets that are too faint to be seen in the more distant parts of the solar system,” said David Jewitt, professor of planetary science and astronomy. at UCLA and co-author of the study said in a NASA press release. “We always suspected this comet must be massive because it is so bright at such a large distance. Now we confirm yes”.

Even with the image provided by Hubble, scientists still have to complete their work in determining its exact size. After all, megacomets are still far away. So the team had to process Hubble images of the comet in a computer model, giving them an approximate estimate of its mass. Now, astronomers can confirm that comet Bernardinelli-Bernstein is much larger than any other comet ever discovered. The previous record was held by C/2002 VQ94, whose nucleus was only 60 miles long.

NASA, ESA, Zena Levy (STScI)

Incredibly, the megacomet is on an interstellar voyage that will take it through our solar system in 2031. Luckily for us, it won’t come any closer than a billion miles away. the sun, passing between Saturn and Uranus. trajectory. It’s also not the first time it’s made such a trip as most of the observed comets originate from the collision of space rocks that created Earth long ago. In fact, the megacomet is orbiting in an elliptical 3 million years long — so it’s been a minute since we last saw it.

Its follow-up approach over the next nine years will provide astronomers with a rare opportunity to scrutinize an object that may still have remnants from the early solar system. With the mighty James Webb Space Telescope opened up and in orbit, we have the opportunity to gain more insight into comets than ever before.

“It was pristine,” Bernardinelli told The Daily Beast last year. “Not much has happened to this object since its formation in the early days of the solar system, and so we can see it as a window into the past.”