JESSICA CHASTAIN, 42, ACTRESS

EXOPLANETS

ASTRONOMERS have for the first time found water in the atmosphere of a planet orbiting of a distant star.

The finding makes the world – called K2- 18b – a plausible candidate in the search for alien life.

Within 10 years, new space telescopes might be able to determine whether K2- 18b’s atmosphere contains gases that could be produced by living organisms.

Until recently, we imagined that other stars were orbited by planets, but only the development of special telescopes has allowed boffins to see them.

So what do we know about these worlds – called exoplanets..? EXOPLANETS – also known as extrasolar planets – are planets which exist outside our solar system. AS of 2019, there have been 4,044 confirmed discoveries of exoplanets. IN 1992, two planets orbiting a distant pulsar – a kind of star on speed – became the first exoplanets to be detected. IN 1995, 51 Pegasi B was the first exoplanet to be discovered orbiting a sun- like star. SINCE 2009, NASA’s Kepler Misson has detected almost 7,000 possible or confirmed planets using its space- based telescope. THE habitable zone – or “Goldilocks zone” – is an area around a star which is at just the right temperature to allow liquid water to exist on a planet’s surface. TWO small Earth- sized planets have been detected in our nearest stellar neighbour, Alpha Centauri – it is possible that one of them may be habitable. ONLY two exoplanets have ever been directly observed using telescopes on Earth. ONE sort of exoplanet is the Hot Jupiter. Hot Jupiters are gas giant planets similar in mass to Jupiter but which orbit very close to their parent star. As a result of the close proximity to their star their surface temperatures exceed 700C – or 1300F. SUPER Earths are “potentially” rocky planets with up to 10 times the mass of Earth. That means you’d be 10 times heavier if you went to one and would probably collapse – up your own arsehole!