A group of NASA scientists, through analysis using the Hubble telescope, confirmed that Discover the biggest comet ever. It is Bernardinelli-Bernstein, an object with a basic mass of about 500 billion tons and a width of 137 kilometers.
According to research published in Astrophysical Journal Letters, the nucleus of this comet is 50 times larger than most known comets. Meanwhile, its mass is a hundred thousand times greater than the mass of a typical comet much closer to the Sun.
Although it is moving close to the Earth at a speed of 35,000 kilometers per hour, The closest will be 1,600 million km from the SunAnd that will happen in 2031.
was the culprit I first discovered by astronomers Pedro Bernardinelli and Gary Bernstein More than 10 years ago While working at the Cerro Tololo Inter-American Observatory in Chile, when it was more than 4.8 billion km from the Sun.
Tip of the iceberg
“We’ve always suspected that This comet must be big Because it’s so bright at such a great distance. Now we confirm it.” said researcher David Jewett, professor of planetary sciences and astronomy at the University of California.
According to the expert, “This comet is literally The tip of the iceberg of many thousands of very faint comets It can be seen in the farthest parts of the solar system.
said lead author Man Tu Hui, who received his Ph.D. from UCLA in 2019 and now works at the Macau University of Science and Technology in Taipa, Macau.
Currently guilty Less than 3 billion km from the sun It is expected that within a few million years it will return to its place in the Oort cloud.
How did they calculate its size?
In order to determine its size, researchers used a telescope Hubble: they took first Five pictures of the comet, on January 8, 2022, and later included previous radio observations.
They admitted that the challenge in measuring this comet was identifying the solid core of the massive dusty coma, the cloud of dust and gas that surrounds it, since the comet is currently too far from Hubble to optically dissolve its core.
Because the Hubble data show a bright-light spike in the core, Hui and colleagues created a Arithmetic model of the surrounding coma and then adjusted to match the Hubble images. finally, They put up the comma glowLeaving the heart behind.
Hui and his team compared the brightness of the core to previous radio observations. From the Atacama Large Millimeter/submillimeter variety, or ALMA, in Chile.
Hubble’s new measurements are close to previous ALMA volume estimates, but convincingly point to a darker nucleus surface than previously thought. “It’s big and blacker than coal”Jewett said.