• Cosmic rule-breaker: Researchers discover rocky planet that defies how worlds form A surprising planetary arrangement around LHS 1903 is pushing scientists to rethink how gas and dust disks evolve over time. • Astronomers have long believed that planetary systems follow a familiar blueprint. • Small rocky planets stay close to their star, while large gas planets orbit much farther away. • Our own solar system fits this pattern perfectly. • However, a newly studied system around the red dwarf star LHS 1903 has turned that neat picture upside down. • The study authors report the discovery of a rocky planet orbiting in the outer reaches of this system, exactly where scientists would expect to find a gas-rich world.
Article Summaries:
- Researchers have identified a rocky planet, LHS 1903 e, orbiting far from its red‑dwarf host star-an arrangement that contradicts the conventional model in which rocky planets form close to stars and gas giants form farther out. The discovery, made with data from ESA’s CHEOPS satellite, shows the outer planet lacks a substantial atmosphere, suggesting it did not acquire one during formation. Simulations rule out atmospheric loss from giant impacts or orbital swapping, pointing instead to an “inside‑out” formation scenario where planets form sequentially at different radii. The finding forces astronomers to reconsider the timing and conditions under which rocky worlds can form.
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