When we hear about the possibility of “interstellar visitors” we would normally think of aliens and fast spaceships. It may surprise you to find out that our Solar System has been recently visited by 2 interstellar visitors. Sadly, these were both comets and not alien spaceships.
Comets are made of ice, dust and rock, so they are sometimes called “dirty snowballs”. Most of these objects come from the outer colder regions of the Solar System and travel around the Sun, like planets. But some have other unknown and mysterious origins...
Astronomers in Japan have studied the paths of two comets as they head out of our Solar System forever. They found that these objects likely don’t call our Solar System home, and instead came from another system from far away.
If this was the case, these comets passed through our Solar System by coincidence before continuing on their way into space.
Only in the past few years have we begun to discover and study comets and asteroids that come from beyond our Solar System.
Who knows where these comets will visit next!
Image credit: NAOJ
There are likely billions of comets orbiting our Sun. When a comet's orbit brings it close to the Sun, it heats up and spews dust and gases into a giant glowing head larger than most planets!