What a Giant Planet Was Baked From express
WASP-121 b is not just a hot ball. It's a world where iron vaporizes and the sky glows with its own heat. A fresh look at it has revealed what 'ingredients' went into making it.
Scientists combined new data from three of Webb's instruments and added ground-based measurements of the host star's composition. The result is a complete picture: the planet's air contains both light gases (water, carbon monoxide) and heavy elements (silicon, iron). But the most intriguing part is the ratio. Silicon relative to oxygen and carbon turned out to be more than three times higher than in the star. Such a 'recipe' couldn't have come from a single source. It seems that in its youth, the planet gathered material from different zones of the protoplanetary disk — some as solid bodies, some as gas. Then it experienced a jolt that tilted its orbit nearly 90 degrees relative to the star's rotation axis. Modeling suggests this could have been a close encounter with another planet or a long dance with a distant stellar companion.
The daytime temperature on WASP-121 b reaches 3000 degrees Celsius — enough to melt steel, and metal vapors float in its atmosphere.
A similar world is described in Arthur C. Clarke's novel 'Rendezvous with Rama'—except there, a scorching object comes to us from interstellar space.