Scientists have found strong evidence of a giant gas planet in the nearest star system to our own. At four-and-a-half light years away, the lifeless planet would be a close neighbour to Earth in astronomical terms and could have moons that sustain life.

The discovery was made using NASA's James Webb Space Telescope, which detected a likely gas giant around Alpha Centauri A- one of three stars in the Alpha Centauri system, just over four light-years from Earth.