“Other galaxies like Andromeda are shooting these ‘spitballs’ at us all the time.” -James Guillochon, coauthor on the new study
Imagine you’re a star passing too close to a black hole. What’s going to happen to you? Yes, you’ll be tidally disrupted and eventually torn apart. Some of the matter will be swallowed, some will wind up in an accretion disk, and some will be accelerated and ejected entirely. But quite surprisingly, the ejected matter doesn’t just come out in the form of hot gas, but it condenses into large numbers of rapidly-moving planets.
An artist’s illustration of large, rapid masses emerging from a point origin in space. Public domain image by Pixabay user Yuri_B.
This population should make up approximately one out of every 1000 rogue planets, but should be uniquely identifiable. The vast majority will move at incredible speeds of around 10,000 km/s, be approximately the mass of Jupiter but will be made out of shredded star material, rather than traditional planetary material. As the next generation of infrared telescopes come online, these ‘cosmic spitballs’ should be one of the most exciting novel discoveries of all.
Rogue planets may not just form from nebulae, but from shredded stars encountering black holes. Image credit: Christine Pulliam / David Aguilar / CfA.