More recent calculations indicate that the core of this star is about 150 kilometers wide.
a National Geographic He says it’s the largest star of its kind in decades. Comet 67P/Churyumov-Gerasimenko, which the European Space Agency’s Rosetta probe orbited from 2014 to 2016, was only about four kilometers wide.
Over the next decade, Bernardinelli-Bernstein will only get brighter as it approaches the inner solar system, moving up to the plane of the planets’ orbits from below.
Its closest approach to Earth will occur on January 21, 2031, when it is expected to be about 1.6 billion kilometers from the Sun, slightly farther than the average distance from Saturn. It will then begin its long retreat back into the outer realms of the solar system, remaining visible until at least 2040, or for decades to come.
Depending on how much gas he releases as his ice evaporates due to the sun’s glare, Bernardinelli Bernstein could appear as bright in the night sky as Titan, Saturn’s largest moon. If so, the comet should be visible in 2031 using an improper amateur telescope.
But Comet Bernardinelli-Bernstein was also known for its distance from the Sun when it was first observed. This icy body comes from the Oort Cloud, an enormous spherical haze of stuff that envelops the Sun thousands of times from Earth.