The landmark discovery detected two chemical gases – Dimethyl Sulfide (DMS) and Dimethyl Disulfide (DMDS), produced primarily by marine phytoplankton- algae on Earth.
- Earlier observations by JWST had identified methane and carbon dioxide in K2-18 b’s atmosphere
More about the Discovery
- Variation in Concentration: Concentration of DMS and DMDS in K2-18b’s atmosphere are around thousands times stronger than on Earth.
- Use of the Transit Method: Astronomers used the Transit Method, wherein as K2-18b transits, JWST detected a drop in stellar brightness.
- Establishing K2-18 b as an Hycean Exoplanet: Hycean Exoplanet is habitable ocean-covered planet underneath a hydrogen-rich atmosphere.
- Accuracy: The observations have reached the ‘three-sigma’ level of statistical significance (0.3% probability of it being a mere chance occurrence) .
About K2-18 b
- It is an exoplanet (planet beyond our solar system mostly orbiting other stars) that is 8.6 times more massive than Earth with a diameter of about 2.6 times of Earth.
- It orbits the cool dwarf star K2-18 in the habitable zone and lies 120 light-years from Earth in the constellation Leo.
About JSWT
- Launched in 2021 as an international partnership between NASA, European Space Agency and Canadian Space Agency to understand the early universe, formation of stars, planets, etc.
- It orbits the Sun 1.5 million kilometres away from the Earth at the second Lagrange point (L2).