Our solar system's early days may have been more crowded than previously understood. A new study hints that up to six giant planets roamed the outer reaches in the first hundred million years, including two 'super Earths' that once orbited near Uranus and Neptune.
The hypothetical super Earths may have disrupted the orbits of existing moons before disappearing themselves, researchers suggest. The findings paint a revised picture of the early outer solar system's dynamics, though the exact fate of these missing planets remains unclear.
This research builds on evidence from meteorites, particularly a rare specimen analyzed by the University of Colorado Boulder. That meteorite offers a window into a lost, Mars-sized planet from the solar system's dawn, providing clues about planetary formation and evolution.
The study relies on computer simulations and meteorite analysis rather than direct observation of the vanished planets. Scientists caution that more data is needed to confirm whether such super Earths truly existed or if alternative explanations fit the evidence.
If validated, the findings would reshape understanding of solar system architecture. They also raise questions about how common such early instability might be in other planetary systems, adding context to exoplanet discoveries.