Hubble confirms that Megacomet on its way to the inner solar system is the largest ever news and research
A giant comet is actually the largest ever seen, confirms new observations from the Hubble Space Telescope.
Extending about 80 miles (129 kilometers) across, the core (or solid center) of the comet, known as C / 2014 UN271 (Bernardinelli-Bernstein), is larger than the state of Rhode Island, according to a statement from NASA. And it is about 50 times larger than the average comet core.
“This comet is literally the tip of the iceberg for many thousands of comets that are too weak to see in the more distant parts of the solar system,” said David Jewitt, co-author of a new study confirming the size of the comet and professor of planetary science and astronomy at the University. of California, Los Angeles (UCLA), said in a statement from NASA. “We have always suspected that this comet must be large because it is so bright at such a great distance. Now we confirm that it is.”
This comet is currently far from Earth and zooms at about 22,000 mph (35,405 km / h). Comet Bernardinelli-Bernstein has been falling against the sun for over 1 million years. But do not worry; the closest it gets to us, according to NASA, is about 1 billion miles (1.6 billion km km), which it will not even reach until 2031.
Previously, the comet that held the title of “largest core” was C / 2002 VQ94, which was discovered in 2002 and is estimated to be about 96 km wide.
This new giant of a comet was first observed in 2010. A few years later, astronomers Pedro Bernardineli and Gary Bernstein found the object in archival data collected by the Dark Energy Survey at the Cerro Tololo Inter-American Observatory in Chile. Since its initial discovery, the object has been studied with a wide range of instruments including both ground-based telescopes and space-based telescopes such as Hubble.
With the observations from Hubble, scientists were finally able to officially confirm the enormous size of this “dirty snowball”. (Comets have the nickname “dirty snowballs” because they consist of stone, ice and other materials and debris, although the objects can vary in composition.) At this time in the comet Bernardinelli-Bernstein’s orbit, where it “only” is about approx. 2 billion miles (3.2 billion km) from the sun, the icy object is about minus 348 degrees Fahrenheit (minus 211 degrees Celsius).
Although cold, this temperature is warm enough to allow carbon monoxide to be sublimated (a process during which solids become gas) from the rocky surface of the comet, creating a “coma”, a casing of dust and gas surrounding a comet fixed center.
“This is an amazing object, given how active it is when it’s still so far from the sun,” said the study’s lead author Man-To Hui, a researcher at Macau University of Science and Technology, in the same statement from NASA. “We guessed that the comet could be quite large, but we needed the best data to confirm this.” So his team used Hubble to take five pictures of the comet on January 8, 2022.
The biggest challenge the team had to confirm the size of the nucleus was to distinguish between the nucleus and the comet’s coma.
Bernardinelli-Bernstein is too far away for Hubble to precisely define its core, but the team discovered a light signal with the telescope showing the comet’s location. They could then use the Hubble observations they had and by using a computer modeling technique to show where the object’s coma would be, they could determine the size of its core.
The team compared its data with previous observations made by the Atacama Large Millimeter / Submillimeter Array (ALMA) in Chile and found that previous size estimates made with ALMA were consistent with Hubble’s new findings. And ALMA’s radio observations allowed them to refine the object’s reflectivity, which showed that the comet’s surface is darker than they expected.
“It’s big and it’s blacker than coal,” Jewitt said.
Scientists believe that the Bernardinelli-Bernstein comet travels from the Oort cloud, the most remote region in our solar system where a huge number of comets are found. It is believed that the comets located in this huge, diffuse cloud formed closer to the sun but were thrown much further out by gravitational interactions with our solar system’s newborn giant planets. And they tend to stay out there unless another gravity pushes them in our path.
This comet, which is so far from Earth and originates in the outermost parts of our solar system, is believed to travel in a 3 million year long elliptical orbit around the sun. Scientists believe that it can travel about half a light-year away from the sun in the longest parts of its orbit.
These findings were described in a study published today (April 12) in The Astrophysical Journal Letters.
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