Exoplanet K2-18b: Discovery of signs of life in a new study!

Exoplanet K2-18b: Discovery of signs of life in a new study!

The exoplanet K2-18B has drawn attention to itself as a major research object in recent years, in particular due to the potential references to life in its atmosphere. This planet, which is located 124 light years from Earth from Earth, is classified as a subneptune and is about 8.6 times heavier and 2.6 times larger than the earth. It circles a red dwarf that only has half the mass of our sun, and lies in the habitable zone, where conditions for liquid water could exist. One year to K2-18b takes around 33 earth days. [Welt]

The current research shows that large quantities of dimethyl sulfide (DMS) and dimethyldisulfide (DMDS) were demonstrated in the atmosphere of K2-18B, which are considered so-called "biosignatures". These molecules are only known on earth from microorganisms, which increases the tension in the scientific community. Nikku Madhusudhan, professor at the Astronomical Institute of the University of Cambridge, leads this study, the results of which were published in the journal "The Astronomical Journal Letters".

scientific knowledge and challenges

The James Webb World Cycling Telescope (JWST), which was developed as the successor to the Hubble world dream telescope, has provided deeper insights into the chemical composition of K2-18B in recent years. The mission, which was launched by an international cooperation between NASA, ESA and CSA, started on December 25, 2021 and reached their orbit shortly afterwards. The JWST is primarily valued for its ability to grasp infrared radiation, which enables it to see through gas clouds and analyze details of the atmospheres of exoplanets.

In 2023, researchers with the JWST discovered promising signs that could indicate living organisms. This discovery met with initial enthusiasm in the scientific community and the public, but current studies also offer a pressed interpretation of the data. For example, researchers emphasize the difficulties of reliably identifying extraterrestrial life and emphasizing that there are concerns about possible false interpretations, since DMS may also occur in other astrophysical contexts.

Some scientists are skeptical of the DMS finds, since this molecule was also discovered on comets. There is also an alternative explanation for the planet: K2-18B could be a large stone colossus with a magma ocean and a dense hydrogen atmosphere. Madhusudhan therefore underlines the need to consider the results with caution and collect further data to confirm or refute the hypotheses.

The way to discover life

Although the researchers do not rule out the possibility of life to K2-18B, it must be emphasized that the biological processes that create DMS should be significantly more active than on earth. The search for further biosignatures in the atmosphere of K2-18B continues, and future observations with the JWST will aim to clarify the presence of DMS with greater security.

The search for extraterrestrial life remains a complex challenge that requires strict analytical standards. With technologies such as the JWST, which has a remarkable sensitivity, scientists are on the threshold on possibly groundbreaking discoveries.