Astronomers track weather on an exoplanet that rains gemstones
by Robert Lea | Jan 12, 2024
The Hubble Space Telescope saw massive cyclones, storms, and weather chaos in the changing atmosphere of WASP-121b, a planet so hot it rains iron, sapphires, and rubies.
Astronomers have taken a three-year-long view of an extreme heavy metal exoplanet called WASP-121b using the Hubble Space Telescope, enabling them to reconstruct its changing atmosphere and weather in a way that has never been done for a planet outside the solar system before. This revealed this violent and turbulent world is even more chaotic than scientists initially suspected.
WASP-121b, a planet that is 1.75 times the size of Jupiter and orbiting so close to its host star that it completes an orbit in just 30 hours, which is one of the shortest orbits ever seen by astronomers.
WASP-121 b is a gas giant exoplanet that orbits an F-type star. Its mass is 1.157 Jupiters, it takes 1.3 days to complete one orbit of its star, and is 0.02596 AU from its star. Its discovery was announced in 2016.
This proximity means that WASP-121b, located around 880 light-years from Earth is tidally locked, meaning one hemisphere of this planet (its “dayside”) permanently faces its star, while the other (the nightside) perpetually faces out into space.
As a result of the constant bombardment of radiation, the dayside temperatures of WASP-121b –which, because of its size and proximity to its star, is classified as a “hot Jupiter” exoplanet — soar up as high as 4,700 degrees Celsius, vaporizing iron and aluminum.
The intense heating of WASP-121b also generates powerful 11,000 miles per hour winds that blow vaporized metals from WASP-121b’s radiation roasted dayside to the planet’s cooler nightside, which still has a fearsome temperature of 730 degrees Celsius. Here these metal clouds mix with minerals, cooling, and falling as rains of iron, rubies, and sapphires.
