Interstellar comet Borisov

An artist’s impression of the interstellar comet Borisov

NRAO/AUI/NSF, S. Dagnello

An average of seven interstellar objects pass by the sun every year, potentially close enough for us to observe and even visit, according to a new analysis. Some of these could even be from another galaxy.

To date, two objects from other planetary systems have been found in our solar system: ‘Oumuamua in 2017 and the comet Borisov in 2019. We know these objects are interstellar in origin because they are moving faster than the escape velocity of our solar system.

Stars like our sun are expected to eject …