Scientists had previously announced the discovery of a molecule in the atmosphere of K2-18b, a planet 124 light-years from Earth, which could potentially signal life. However, new analysis by University of Chicago researchers has raised significant doubts about the finding.
The team, led by Rafael Luque, reviewed data from multiple observations of the planet using telescopes such as the James Webb Space Telescope and Hubble. They found that the readings were too “noisy” to confirm the presence of dimethyl sulfide or dimethyl disulfide, two molecules associated with life on Earth.
The researchers noted that interpreting data from telescopes is challenging due to the extreme distance between the planet and Earth, making it difficult to observe the planet directly. Instead, scientists rely on indirect clues, such as analyzing the light that filters through the planet’s atmosphere.
Study co-author Michael Zhang explained that even with better data, it would be hard to uniquely identify a particular molecule due to its similarity in spectral profiles to other compounds. The analysis concluded that multiple molecules could fit the bill for what the telescope saw, including ethane, which is found in many planets’ atmospheres and does not indicate life.
The researchers emphasized that their findings should not be overshadowed by previous claims of detecting life on K2-18b. They aim to provide a fuller view of the data and encourage caution when making such extraordinary claims.
Source: https://phys.org/news/2025-05-life-deep-space.html