The Comet Bernardinelli-Bernstein (BB), represented in this artists rendition as it might look in the outer Solar System, is estimated to be about 1000 times more massive than a typical comet. The largest comet found in modern times, it is among the most remote comets to be discovered with a coma, which means ice within the comet is vaporizing and forming an envelope of dust and vapor around the comets core. Since comets move, he had to layer the images so that comet BB was exactly aligned in each frame.
The Comet Bernardinelli-Bernstein (BB), represented in this artists rendition as it may look in the external Solar System, is estimated to be about 1000 times more enormous than a normal comet. The biggest comet discovered in modern-day times, it is among the most remote comets to be found with a coma, which suggests ice within the comet is forming an envelope and vaporizing of dust and vapor around the comets core. Credit: NOIRLab/NSF/AURA/ J. da Silva
University of Maryland astronomers found that comet Bernardinelli-Bernstein is amongst the most remote active comets from the sun, offering essential details about its structure.
The largest comet ever discovered became active much further from the sun than previously thought, according to a new research study by University of Maryland astronomers.
Just one other active comet– suggesting one that has formed an envelope of dust and vapor referred to as a coma– has actually been observed farther from the sun; however, it was much smaller sized than comet Bernardinelli-Bernstein (BB), which at 100 km in size overshadows every other recognized comet by a large margin. (Halleys comet, by contrast, is 15 km in diameter, while 1 km is normal.).
The finding, which will help astronomers determine what BB is made of and provide insight into conditions that existed billions of years back during the formation of our planetary system, was released on November 29, 2021, in The Planetary Science Journal.
” These observations are pushing the distances for active comets considerably farther than we have formerly known,” said Tony Farnham, a research study scientist in the UMD Department of Astronomy and the lead author of the research study.
Frequently called “filthy snowballs” or “icy sleazebags,” comets are conglomerations of dust and ice left over from the solar systems early days. How warm they must be to start vaporizing as their orbit carries them closer to the sun depends on what type of ice they include: water, co2, carbon monoxide gas or some other frozen substance.
Researchers first discovered comet BB beyond the orbit of Uranus in June using data from the Dark Energy Survey, a global effort to survey the sky over the Southern Hemisphere. It recorded the intense nucleus of the comet but did not have high-enough resolution to reveal the envelope of dust and vapor that forms when the comet becomes active.
When Farnham found out about the discovery, he immediately questioned if images of comet BB had been captured by the Transient Exoplanet Survey Satellite (TESS), which observes one location of the sky for 28 days at a time. He believed TESSs longer exposure times could provide more information.
Since comets move, he had to layer the images so that comet BB was specifically aligned in each frame. That strategy eliminated any errant specks from specific shots while magnifying the image of the comet, which enabled researchers to see the hazy radiance of dust surrounding BB, evidence that BB had a coma and was active.
Referral: “Early Activity in Comet C/2014 UN271 Bernardinelli– Bernstein as Observed by TESS” by Tony L. Farnham, Michael S. P. Kelley and James M. Bauer, 29 November 2021, The Planetary Science Journal.DOI: 10.3847/ PSJ/ac323d.