Rogue Planet May Have Triggered Chaos In Solar System’s Early Days

The Solar System’s tumultuous youth has long been a subject of fascination for astronomers. A recent study proposes that a rogue planet may have played a pivotal role in reshaping the orbits of the gas giants, leaving an indelible mark on the system’s architecture. This phenomenon, known as the giant planet instability, has been linked to several distinctive features of the Solar System, including Jupiter’s co-orbital asteroids, the irregular satellites of the giant planets, and the orbital structures of the Kuiper belt and asteroid belt.

According to researchers Sean Raymond and Nathan Kaib, the timing of this instability appears to have occurred early, likely within 5-20 million years after the Solar System’s formation, based on evidence from meteorites. However, the trigger for this event has remained elusive – until now. The duo ran 3,000 computer simulations to test whether stellar flybys could have destabilized the young planetary system.

Their findings suggest that a close encounter with a free-floating planet or low-mass brown dwarf could have set off a chain reaction, ultimately leading to the Solar System’s current configuration. The simulations involved subjecting a stable, resonant chain of giant planets to a single flyby, with the perturbing object ranging from one Jupiter mass to 10 solar masses, and passing ← →