A peculiar planetary system, where planets are arranged in an 'inside-out' configuration, has left astronomers astounded. This system challenges conventional understanding and suggests a unique formation process for these distant worlds. In our Solar System, the inner planets are small and rocky, while the outer ones are gas giants. However, a star named LHS 1903, discovered in the Milky Way's thick disc, defies this pattern. An international team of astronomers, analyzing data from various telescopes, initially found three planets orbiting the red dwarf star, with the expected rocky-gaseous sequence. But a closer look by Europe's Cheops space telescope revealed a fourth, rocky planet farther out, creating an 'inside-out' arrangement. This discovery has sparked curiosity and debate among scientists. Thomas Wilson, the lead author of the study, explains that this system suggests a planet formation process where rocky planets form far from their star, which is contrary to the widely accepted theory. The conventional theory posits that planets form simultaneously in a protoplanetary disc, but the LHS 1903 system may have formed one at a time, running out of gas before the fourth planet could form. This finding raises questions about our understanding of planetary formation and invites further exploration and discussion in the scientific community. As astronomers continue to uncover more exoplanets, they are revisiting and refining their theories, highlighting the importance of ongoing research and the potential for new discoveries.
