In a groundbreaking discovery, scientists have detected what may be the strongest evidence of alien life yet on a planet orbiting a star 120 light-years from Earth. The exoplanet, K2-18b, has shown the presence of a molecule in its atmosphere that, on Earth, is linked to living organisms. Published in the Astrophysical Journal Letters, the study suggests the planet could be covered by a vast ocean beneath a hydrogen-rich atmosphere. Lead researcher Nikku Madhusudhan of the University of Cambridge says the chemical signature is consistent with marine phytoplankton and bacteria. “If the association with life is real, then this planet will be teeming with life,” he said. The levels of these molecules are thousands of times higher than those on Earth. While the data is promising, researchers urge caution. “Extraordinary claims require extraordinary evidence,” said astronomer Laura Kreidberg. Still, the findings mark a major step forward in the search for extraterrestrial life. “This could either reveal a new chemical process or the first signs of biological activity beyond Earth,” said co-author Mans Holmberg. Scientists hope to confirm the signal within the next two years.