Because of special circumstances formed on this side of the planet, scientists do not rule out the presence of clouds of iron and aluminum oxide, as a mineral that forms the basis for sapphire. The results of the study were published in the scientific journal Nature Astronomy.
One of the authors of the article in this regard, a researcher at the Massachusetts Institute of Technology, Thomas Michael Evans, said: “Our data indicate that the dark side of WASP-121b is cool enough to allow the presence of clouds of iron vapor and corundum vapor, as the mineral that forms the basis of sapphire. Clouds boundary between the two hemispheres of the planet, a strange rain of liquid gems is falling.”
Hot Jupiters are gas giants that are a short distance from their star, much closer than the distance between Mercury and the Sun. Therefore, the temperature of the atmosphere on such planets rises to several hundred degrees Celsius. Due to its proximity to the star, a year on hot Jupiter usually only lasts for several Earth days.
One of the hottest planets of this type is WASP-121b, which is located in the constellation Puppis at a distance of 850 light-years from Earth. Gravitational interactions with the star cause WASP-121b to spin so fast that one side is always pointed toward the sun, while the other is constantly immersed in darkness. As a result, the luminous side of WASP-76b is heated to 2300-2500°C, while the other side is several hundred degrees cooler.
Astronomers tried to study the dark side of this planet for a long time, but they always failed to achieve this, because the night side produces 10 times less light and heat than the day side, and scientists were unable to measure the exact temperature on the dark side of the hot Jupiter and know the components and behavior of its atmosphere.
For two years, astronomers monitored the rotation of WASP-121b around its star using infrared instruments at the Hubble Space Laboratory, and tracked how the brightness of the glow caused by water vapor molecules changed as the planet moved in its orbit, thanks to which they separated the incoming rays from the visible sides. and dark.
Analysis of images of the dark side of WASP-121b showed that the difference in temperature between the light and dark sides of this hot Jupiter was higher than previously assumed by planetary scientists. The hottest point of WASP-121b was heated up to 2,700°C, and the coldest point was heated to just 500-800°C.
Because of this large temperature difference, several strange phenomena can occur simultaneously, including winds of more than 18,000 km/h, and strange clouds of metal fumes such as corundum, perovskite, and forsterite.
Scientists assumed that because of these clouds, raindrops of liquid gems and droplets of frozen minerals fall on the planet.