The fourth planet in the system is a rocky world, while the second and third ones are gas planets.
A rocky exoplanet in the LHS 1903 system defies planet formation models, hinting that gravitational upheaval reshaped the red dwarf’s four worlds.
A newly studied solar system breaks the usual planet pattern, raising fresh questions about how rocky and gas planets form.
The planets around a nearby star seem to be in the wrong order, hinting that they formed through a different mechanism than the familiar one by which most systems grow ...