NASA verified that the biggest comet ever detected has a diameter of around 85 miles and is now officially the largest comet ever spotted after Hubble Space Telescope studies.
C/2014 UN271 (Bernardinelli-Bernstein (BB) was discovered in 2014 by two astronomers, Pedro Bernardinelli and Gary Bernstein, using Dark Energy Survey archived pictures. BB's diameter was previously estimated to be between 62 and 124 miles, but NASA has officially verified the comet's nucleus diameter to be 85 miles wide using the Hubble Space Telescope.
According to NASA's blog, BB has surpassed the previous record-holder comet C/2002 VQ94, which has an approximate nucleus diameter of 85 miles. The space agency adds that the comet has been hurtling toward Earth for a million years and will pose no danger to the planet when it reaches its closest approach in 2031, coming within a billion miles of Earth or around the distance between Earth and Saturn.
Consider that if the whole area of BB is considered, it will be greater than the state of Rhode Island.
"This is an amazing object, given how active it is when it's still so far from the Sun. We guessed the comet might be pretty big, but we needed the best data to confirm this," said the paper's lead author Man-To Hui of the Macau University of Science and Technology, Taipa, Macau.
"This comet is literally the tip of the iceberg for many thousands of comets that are too faint to see in the more distant parts of the solar system. We've always suspected this comet had to be big because it is so bright at such a large distance. Now we confirm it is," said David Jewitt, a professor of planetary science and astronomy at the University of California, Los Angeles (UCLA), and co-author of the new study published in The Astrophysical Journal Letters.
Reference(s): NASA, Peer-Reviewed Research Article