Among the most extreme exoplanets known, some orbit so close to their stars that vast regions become oceans of molten lava. Astronomers have recently modeled the weather cycle on one such world, K2-141b.
Earth has its harsh spots, but they pale compared to K2-141b, a rocky super-Earth located 202 light-years away. Discovered in 2018 by NASA's Kepler mission, this planet orbits an orange dwarf star in just 6.7 hours, creating extraordinary conditions that researchers at York University have simulated. As experts in exoplanetary atmospheres, they've revealed a world unlike anything in our solar system.
"This study is the first to predict weather conditions on K2-141b, observable by next-generation telescopes like the James Webb Space Telescope from hundreds of light-years away," explains lead researcher Giang Nguyen of York University.
Tidally locked like the Moon to Earth, K2-141b shows only one face to its star. The dayside reaches surface temperatures of about 2730°C, with astronomers estimating a global magma ocean up to 100 kilometers deep.
Simulations published in the Monthly Notices of the Royal Astronomical Society describe a cycle mirroring Earth's water cycle. Rocks and minerals like sodium, silicon monoxide, and silicon dioxide evaporate from the surface, forming a tenuous atmosphere. Supersonic winds gusting at 5,000 kilometers per hour carry this hot, rocky vapor toward the nightside.
There, temperatures plummet to around -200°C, causing the rocks to condense and fall as rain, replenishing the magma ocean.
This research, grounded in peer-reviewed astrophysics, illuminates early planetary formation. Earth itself was once a molten world 4.5 billion years ago, cooling to form its crust. Lava planets like K2-141b offer a window into that violent epoch.
