A hellish ‘hot Jupiter’ planet, located relatively close to Earth, would likely smell like rotten eggs if we ever made the journey to visit it. This revelation comes from new data collected by the James Webb Space Telescope (JWST). HD 189733 b, a gas giant situated about 64 light-years away in the Vulpecula constellation, orbits its star at an incredibly close distance – 13 times closer than Earth orbits the Sun. This proximity leads to extreme temperatures on the exoplanet’s surface, reaching a scorching 1,700 degrees Fahrenheit (925 degrees Celsius), hot enough to melt certain rocks into magma. Previous observations had already revealed that the exoplanet experiences molten glass rain, driven by winds reaching speeds of up to 500 mph (800 km/h), three times faster than a Category 5 hurricane on Earth. In a new study, published in the journal Nature, researchers utilized JWST to delve deeper into the unique characteristics of HD 189733 b. Beyond measuring the levels of carbon dioxide, oxygen, water, and heavy metals in the exoplanet’s atmosphere, the team discovered the presence of hydrogen sulfide. This toxic and flammable colorless gas, known for its rotten egg odor, is emitted by decaying organic matter and volcanoes on Earth. Scientists had previously suspected that hydrogen sulfide could be found on distant gas giants, based on the presence of the same molecule in the atmospheres of Jupiter and Saturn. However, this gas has rarely been detected outside of the solar system, except for trace amounts in the interstellar medium. The discovery of hydrogen sulfide on HD 189733 b marks a significant milestone. “This discovery is an important stepping stone for finding this molecule on other planets and gaining more understanding of how different types of planets form,” stated study lead author, an astrophysicist at Johns Hopkins University in Maryland. The presence of hydrogen sulfide is particularly important because it indicates the presence of sulfur, a vital element for building more complex molecules. Sulfur is also a key element for almost all lifeforms on Earth. However, given the hellish temperatures and weather conditions on HD 189733 b, it is highly unlikely to support life. Despite this, the detection of hydrogen sulfide on this distant world opens up the possibility of similar exoplanets potentially sustaining some form of alien life. The researchers are now planning to use JWST to study similar ‘hot Jupiters’ to determine if they too contain hydrogen sulfide. JWST has revolutionized the way scientists study exoplanets like HD 189733 b. Its cutting-edge instruments can detect various chemicals across the cosmos, including methane, ammonia, and water vapor. Last year, the telescope discovered a similar molecule, known as dimethyl sulfide, in the atmosphere of another exoplanet. This gas, previously known only to be produced by living organisms in Earth’s oceans, hinted at the possibility of life on this alien world and others. However, subsequent research refuted the presence of this molecule. Scientists also believe that if JWST were positioned on the opposite side of the star from the exoplanet, it would be able to detect the light reflecting off the exoplanet, allowing for a more comprehensive analysis of its atmosphere and composition. This discovery, along with the continued observations of exoplanets using JWST, promises to unlock a wealth of information about the universe and potentially reveal the existence of life beyond Earth.