Iron Rain on WASP-76b Makes for a Strange Exoplanet
Iron rain on WASP-76b is weird, and new studies show this massive, incendiary world is even weirder than we thought.
Somewhere around 640 light years from Earth, a massive world 90 percent as large as Jupiter races around its parent star, an astronomical hairsbreadth from the stellar furnace.
Discovered in 2016, WASP-76b races around its F-class star once every 43 hours. These stars are yellow-white, and their metal-rich surface glows at temperatures from 5,700 — 7,000 Celsius (10,300–12,600 F).
Vast quantities of heat from the star (WASP-76) pummel the planet, exciting that world to extreme temperatures. This inferno vaporizes iron on the starlit-side of the world, lifting mammoth quantities of the metal into the atmosphere. As the gas circulates around the Jovian-class planet, entering the night side of the world, the element condenses, falling as iron rain on WASP-76b.
“It’s remarkable that with today’s telescopes and instruments, we can already learn so much about the atmospheres — their constituents, physical properties, presence of clouds and even large-scale wind patterns — of planets that are orbiting stars hundreds of light-years away,” said co-author Ray Jayawardhana, professor of astronomy at Cornell University.
