William sent in the link to https://www.yahoo.com/news/turns-megacomet-more-80-miles-192641117.html … the Bernardinelli-Bernstein Comet, or C/2014UN271, was discovered by astronomers at the University of Pennsylvania, Gary Bernstein and Pedro Bernardinelli. Later, it became known as the ‘megacomet’ as it appeared to be a monster. NASA astronomers used the Hubble Space Telescope to study it more closely and a research paper has just been published in the Astrophysical Research Letters, on the subject. It is now confirmed the nucleus is 80 miles in width – roughgly 50 times the size of your run of the mill comet. Although it is still far out in the outer reaches of the solar system it is heading towards the planetary zone at the heart of it, reaching the closest point to earth in 2031. It will pass between the orbits of Saturn and Uranus, but apparently will come nowhere close to the Sun. It has an elliptical orbit that is estimated to take 3 million years to traverse. Its upcoming visit will provide astronomers with a rare opportunity, the chance to study it at a suitable distance.
The same story is at https://phys.org/news/2022-04-billion-year-old-relic-early-solar.html … where we learn it is travelling at approximately 22,000 miles per hour. It has a multi-million miles long tail travelling in its wake, and its nucleus is described as blacker than coal, a common description of comet deities in myth and legend. It has an estimated mass of 500 trillion tones, a hundred thousand times greater than the mass of a typical comet. See also https://doi.org/10.3847/2041-8213/ac626a …