Discover the Exoplanet WASP-121b, Where Iron Winds and Extreme Temperatures Challenge Our Astronomical Understanding
Imagine a world where wild winds sweep across the sky carrying molten iron and titanium. This place exists. WASP-121b, also known as Tylos, is an exoplanet 900 light-years away, located in the constellation Puppis.
Astronomers, using the Very Large Telescope (VLT) of the European Southern Observatory (ESO), mapped its atmosphere in three dimensions. It is the first study with such depth and detail.
It is one of the most extreme exoplanets ever found. Julia Victoria Seidel, an ESO researcher and lead author of the study, describes: “The atmosphere of this planet behaves in ways that challenge our understanding of how climate works — not just on Earth, but on all planets, it seems like something out of science fiction.”
-
Scientists found hidden within the plants a DNA archive that survived intact for more than four hundred million years.
-
NASA astronauts have captured from the International Space Station rare lightning that shoots upwards instead of falling to Earth, like the giant jet photographed in 2025 by astronaut Nichole Ayers, high-altitude electrical phenomena almost impossible to see from the ground.
-
Amid fears of a Chinese invasion, Taiwan unveiled war robot dogs in three versions: one for reconnaissance, one for surveillance, and an armed one for fire support. The military has already shown interest, although no formal purchase has been made so far.
-
With no boss around, no traffic, and more comfort at home, remote work has gained millions of fans, but now a study links the model to a worrying increase in mental suffering.
A World of Extremes
Tylos is classified as an ultra-hot Jupiter. It is a gas giant that orbits its host star so closely that a year there lasts only 30 Earth hours.
The planet is tidally locked, always keeping the same side facing its star. This side reaches temperatures that can exceed 2,500 °C, enough to vaporize metals like iron.
Meanwhile, the opposite side remains in eternal night and is significantly colder.
This extreme temperature difference creates a chaotic and violent atmosphere. Natural winds emerge to balance the heat and cold, creating an environment with unpredictable conditions.
Iron Winds and Atmospheric Layers
Astronomers are trying to observe Tylos during a complete transit in front of its star. To do this, we combined the light from the four units of the VLT telescope and used the ESPRESSO instrument. The result was a detailed view of the planet’s atmosphere.
They detected the presence of iron, sodium, hydrogen, and titanium. These elements served as markers, allowing the mapping of winds in three distinct layers.
Iron winds dominate the lower layer. Above, a jet stream moves rapidly. At the top, hydrogen winds sweep across the planet.
“What we discovered was surprising: a jet stream rotates the material around the planet’s equator, while a separate flow in lower levels of the atmosphere moves gas from the hot side to the cooler side,” explains Seidel. “This type of climate has never been seen before on any planet.”
Jet Stream of 70,000 km/h
The jet stream on Tylos is impressive. It covers half of the planet and reaches speeds of up to 70,000 miles per hour.
For comparison, this is almost double the speed of the fastest winds ever recorded on another exoplanet. “Even the strongest hurricanes in the solar system seem calm in comparison,” comments Seidel.
These extreme speeds demonstrate the turbulent nature of Tylos’s atmosphere. It is an environment where even the most intense weather events from our solar system seem weak.
Challenges to Planetary Theories
Tylos did not fit known patterns. The jet streams of the planets in our solar system are driven by internal temperature differences.
On Tylos, however, the jet stream seems to be influenced by the intense heat from its star and possibly by its magnetic field.
“What we see now is actually exactly the opposite of what comes out of the theory,” says Seidel. This indicates that astronomers still have much to learn about the formation and behavior of planets outside our solar system.
The Future of Exoplanet Research
Tylos is a strange world. However, many other similar planets likely lie beyond our solar system. The VLT has already proven capable of studying ultra-hot Jupiters like Tylos.
However, smaller planets, more similar to Earth, are still beyond current reach. The construction of the Extremely Large Telescope (ELT), also in Chile, promises to change that.
Bibiana Prinoth, a PhD student at Lund University and ESO, led a complementary study and comments: “The ELT will be a game-changer for studying exoplanet atmospheres. This is just the beginning of what we can achieve.”
With advanced instruments, the ELT will be able to probe the atmospheres of rocky exoplanets. Who knows, in the future, it might even discover signs of habitability — or even life.
With information from ZME Science.

-
1 person reacted to this.