I/ATLAS isn't just fascinating because it is the third interstellar visitor found in the solar system; new research suggests it's also the oldest comet ever seen, at over 7 billion years old.

Astronomers tracking an interstellar object flying through the solar system think it comes from a star at least 8 billion years old, almost twice the age of our sun

Kareta says that come October, when the comet gets closer to Earth, "under dark skies ... with a big telescope and some patience, maybe you might be able to see it." Which he says would be special because, "that might be the first time anyone has actually seen the light from an interstellar object with their own eyes."