An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit before shoving four of the solar system's planets onto a different course.

Beyond Neptune lies the Kuiper Belt, a vast expanse of icy bodies that may hold clues to the solar system’s formation. These ...

This may explain the strange properties of the orbits of our solar system's planets ... orbits of many planets. More NASA, ESA, Caltech / ISTOCK / GETTY IMAGES PLUS "[T]he puzzle for theoretical ...

Jan. 15, 2025 — New observational data and simulation models have confirmed a new type of planet unlike anything found in the Solar System. This provides another piece of the puzzle to ...

"[T]he puzzle for theoretical astrophysics ... Because many close-matching simulations had the planet-like object swooping through the inner solar system, the researchers created an additional ...