The largest-known comet has been discovered to be active at a near-record distance.

Comets are said to be space debris that were leftovers far away at the end of the solar system. As far away as they seem to be, these chunks of dirty ice balls find their way closer to the sun. That’s why we see them here on Earth. Have you ever seen one? Not really? Whatever. A recent study by astronomers from the University of Maryland found that the largest-known comet ever discovered was pretty much active much farther away from the sun than previously believed.

Once Upon A “Big Boy”

The recent study which was published in the Planetary Science Journal, astronomers found the comet C/2014 UN271 Bernardinelli-Bernstein — let’s call it ‘BB’ for simplicity — was very active at a near-record distance. The comet is estimated to be about 1000 times more massive than the average comet. According to astronomers from the University of Maryland, they discovered that BB is among the most distant active comets from the sun.

Image: University of Maryland | position of comet C/2014 UN271 Bernardinelli-Bernstein in the solar sytem away from the sun

BB also has all features of a typical comet — an icy core that’s trailed by a coma. What this means is that, its icy core is vaporizing and forming an envelope of dust that’s trailing it through the solar system. In addition, key information about its composition was also found. This makes BB the largest-known comet discovered in modern times that’s also the farthest ever discovered to be an active comet. Now that’s the “Big Boy” of all comets.

Comet Halley — the only other active comet also with a dusty vaporizing trail — has been observed farther away from the sun. However, Halley is pretty much smaller than comet BB, which is roughly 100 kilometers (62 miles) in diameter, and totally dwarfs any other known comet ever discovered. In comparison, Halley is just 15 kilometers (9.3 miles), whereas a typical comet is roughly a kilometer (0.62 miles) in diameter.

Icy, Or Dirty In Space?

Image: NASA Space Exploration | artistic concept comet Halley as seen by satellite in space

Comets are often thought of as “dirty ice balls,” conglomerations of icy gas and dust that were leftover after the formation of the solar system. Their composition depends on what type of ice they contain: water, carbon dioxide, carbon monoxide, or whatever in the frozen depths of the solar system. These are the vaporizing agents that causes the coma as they get closer to the sun.

BB was first discovered in June by scientists far beyond the orbit of Uranus. They obtained data from the Dark Energy Survey, an international effort to survey the sky over the Southern Hemisphere. They captured it’s bright nucleus, but unfortunately had not enough resolution to resolve it’s coma when it becomes active. These findings will help astronomers determine what BB is actually made of, and will also provide an insight into what conditions were like eons ago during the formation of the solar system.

“These observations are pushing the distances for active comets dramatically farther than we have previously known,” said Tony Farnham, a research scientist at the University of Maryland’s Department of Astronomy, and the lead author of the study, in a statement.

Largely Active In Deep Space

Image: University of Maryland | artistic concept of comet C/2014 UN271 Bernardinelli-Bernstein

Farnham, together with his colleagues, research professor James Bauer and associate research scientist Michael Kelley, combined thousands of images captured by the Transient Exoplanet Survey Satellite (TESS), an observatory satellite that searches a point in the sky for 28 days at a time. But TESS couldn’t provide all the resolved details they were hoping for. So they had to stack individual images of BB, one over the other, that was captured from 2018 through 2020.

Farnham was able to increase the contrast and get a resolved image of the comet. But unfortunately again, comets move, so they had to layer the images of BB so they could precisely align it’s position in each frame. This way, astronomers were able to remove errant specks from the individual shots by amplifying the images. This revealed the vaporizing effect which proved that BB had a coma, and was indeed an active comet.

Source: University of Maryland

Read more facts like this one in your inbox. Sign up for our daily email here.

The Factionary is ever ready to provide you with more interesting content for your reading pleasure. If you’re amazed by our work, you can support us on Patreon by a donation fee of your choice. Thank you!

Written by: Nana Kwadwo, Sun, Dec 05, 2021.


This site uses Akismet to reduce spam. Learn how your comment data is processed.