The study of exoplanets, worlds which orbit stars other than our sun, is currently being transformed by the new James Webb Space Telescope (JWST). We will shortly gain our first insight into conditions on rocky, potentially Earth-like worlds beyond our solar system. One of these distant worlds might host life. But could we detect it?
We may be able to spot signs of life in the composition of the planet’s atmosphere. We can use a technique called transmission spectroscopy – which divides up light by its wavelength – to search for traces of different gases in starlight as it passes through a planet’s atmosphere.
