These planets – or “planemos” – just orbit each other. Their discovery challenges the current theory that planets are thought to form out of the disks of gas and dust that surround newborn stars.
Now that we’ve discovered these planetary mass objects with their own little infant planetary systems, the definition of the word ‘planet’ has blurred even more.
By using the term planemo, the researchers are purposely avoiding the debate over whether [they] should be called planets.