Astronomers puzzle over ‘inside out’ planetary system

Astronomers have observed a planetary system that challenges current planet formation theories, with a rocky planet that formed beyond the orbits of its gaseous neighbors, possibly after much of the planet-forming material had been used up.

The system, observed using the European Space Agency’s Cheops space telescope, consists of four planets – two rocky and two gaseous – orbiting a relatively small and dim star called a red dwarf about 117 light-years from Earth in the direction of the Lynx constellation.