A long-lost rogue planet could explain unexpectedly distant asteroids

The outer solar system holds some chunks of ice and rock that orbit so far from the sun it’s hard to imagine how they got there – but an ancient rogue planet may hold the key

A long-lost rogue planet could explain unexpectedly distant asteroids
The outer solar system holds some chunks of ice and rock that orbit so far from the sun it’s hard to imagine how they got there – but an ancient rogue planet may hold the key