In 2022, researchers discovered many exoplanets with unusual characteristics such as iron rain or silicate clouds.
TOI-2180 b
Simulation of planet TOI-2180 b. (Image: NASA).
Astronomers have discovered a mysterious large planet the size of Jupiter orbiting its host star. The planet, named TOI-2180 b, is located relatively close to Earth, at a distance of 379 light-years. This exoplanet has a diameter similar to Jupiter but is nearly three times more massive. The difference in density suggests that the planet formed differently from Jupiter.
What makes TOI-2180 b unusual is that it takes 261 days to orbit its star, which is much longer than most gas giants discovered so far. Another strange feature is the planet’s average temperature, which is around 77 degrees Celsius. Although warmer than Jupiter and Saturn, TOI-2180 b is still quite cold compared to many other giant exoplanets, according to the lead researcher Paul Dalba from the University of California, Riverside.
TOI-1075 b
Simulation of planet TOI-1075 b. (Image: NASA).
The extremely hot super-Earth is one of the largest planets ever discovered. This exoplanet is covered in magma, with a year lasting only half a day. TOI-1075 b was found by NASA’s Transiting Exoplanet Survey Satellite (TESS). The planet has a super-hot surface temperature of 1,050 degrees Celsius due to its proximity to its host star, a small red-orange star approximately 200 light-years from Earth. In addition to its extreme weather and a short orbital period of just 14.5 hours, TOI-1075 b is nearly ten times the size of Earth.
WASP-76 b and WASP-121 b
Simulation of iron rain on planet WASP-76 b. (Image: ESO)
Tomás Azevedo Silva, a PhD student at the University of Porto, Portugal, and his team discovered barium metal in the atmosphere of two exoplanets. This is the heaviest element ever found in the atmosphere of an exoplanet. The discovery on the super-hot gas giants WASP-76 b and WASP-121 b could reveal more about the Jupiter-like planets that are close to their stars and are tidally locked, thus having one side always facing the star and the other side relatively cool.
WASP-76 b has daytime temperatures reaching up to 2,400 degrees Celsius, hot enough to vaporize iron and many other metals. When the vaporized iron is blown toward the cooler nighttime side, it condenses and falls as “iron rain.”
WASP-103b
The ball-shaped planet WASP-103b. (Image: ESA).
The exoplanet WASP-103b resembles a soccer ball more than a typical sphere. The strange shape of the super-hot planet WASP-103b, located over 1,000 light-years from Earth, is a result of being stretched by the gravitational pull of its host star.
WASP-103b takes only one day to orbit its host star, subjecting it to strong radiation and gravitational forces. By observing several transits of the planet across the surface of the host star, researcher Babatunde Akinsanmi from the University of Geneva was able to measure its level of distortion.
VHS 1256 b
Simulation of a brown dwarf. (Image: NASA)
The James Webb Space Telescope has discovered a planet covered by clouds containing silicate particles resembling sand. The planet orbits a brown dwarf that is nearly 20 times larger than Jupiter. Although brown dwarfs cannot burn hydrogen in nuclear reactions, they can emit light and heat through the burning of deuterium, a rarer isotope of hydrogen. Brown dwarfs are unusual celestial bodies, significantly heavier than planets but too light to be stars.
The brown dwarf VHS 1256 b orbits two red dwarfs located 72 light-years away from Earth in the constellation Corvus. Data from the James Webb Telescope reveals that VHS 1256 b has thick clouds made of silicate particles.
