Largest comet ever seen hurtling toward our solar system

The largest comet ever detected, Bernardinelli-Bernstein, is returning to our solar system.

The comet is located 29 astronomical units (AU) – 29 times the distance between Earth and the Sun – and is therefore expected to arrive in about a decade, according to new research published on the preprint server

At present, the 93-mile-wide comet is located in the Oort Cloud, a vast array of icy mountain-sized rocks, but a glowing tail or ‘coma’ behind it indicates it is on its way. approaching the hotter inner solar system. .

Fortunately, the giant boulder poses no threat to the planet and will likely pass by the planet outside of Saturn’s orbit, 10.97 AU from the sun. This means humans won’t be able to see the comet without using equipment, such as telescopes, but it’s significantly closer than the comet’s most recent approach.

The last time Bernardinelli-Bernstein returned, 3.5 million years ago, it approached within 18 AU of our Sun, before receding 40,000 AU.

“We conclude that BB is a ‘new’ comet in the sense that there is no evidence for [a] previous approach closer than 18 AU,” the researchers wrote, as quoted in LiveScience.

The comet was first spotted 4 billion kilometers from our solar system in 2014, roughly the same distance as Neptune.

“My phone kept ringing – I didn’t expect reception on [scientific] community has given to discovery,” Pedro Bernardinelli, a postdoctoral researcher at the University of Washington, told National Geographic.

Studying the comet is crucial to scientists’ understanding of the solar system’s ancient history, the scientists said, and could reveal more about the mysterious Oort cloud.

Although Bernardinelli-Bernstein is almost certainly not harmful to Earth, space agencies are developing contingency plans for more dangerous threats from space.

Chinese researchers want to send 23 Long March 5 rockets from the country to practice diverting asteroids away from Earth. They will target the asteroid Bennu, which will be less than 7.5 million kilometers from Earth’s orbit with a one in 2700 chance of hitting the planet between 2175 and 2199.

Nasa, meanwhile, is targeting a rock called Didymos – the size of Egypt’s Great Pyramid – by deliberately crashing a spacecraft into it in an effort to alter its motion in space.

Arline J. Mercier