New research reveals that exoplanet HD 189733 b contains hydrogen sulfide, a gas with a strong, egg-like odor. Using data from the James Webb Space Telescope, scientists also found carbon dioxide, oxygen, water, and heavy metals in its atmosphere. Located 65 light years away in the constellation Vulpecula, HD 189733 b is known for extreme temperatures and severe weather, earning it the nickname “hot Jupiter.” The discovery of hydrogen sulfide, a molecule previously undetected outside our solar system, offers insights into planetary formation.