NASA: Three 'Earth-like planets' in newly discovered solar system
Scientists have spotted three 'Earth-like planets' in a newly discovered solar system which they believe may support life.
Astronomers have detected no less than seven Earth-sized worlds orbiting a cool dwarf star known as TRAPPIST-1, which lies 39 light years from Earth.
The six inner planets lie in a temperate zone where surface temperatures range from zero to 100C.
But at least three are thought to be capable of having oceans, increasing the likelihood of life.
No other star system known contains such a large number of Earth-sized and probably rocky planets.
Nasa said it would take about 44 million years to get to the solar system on a passenger plane.
British astronomer Dr Chris Copperwheat, from Liverpool John Moores University, who co-led the international team, said: "The discovery of multiple rocky planets with surface temperatures which allow for liquid water make this amazing system an exciting future target in the search for life."
A robotic telescope operated by Liverpool John Moores University played a major role in the discovery reported in the journal Nature.
It was one of a number of ground-based instruments that supported observations made by American space agency Nasa's orbiting Spitzer telescope.
The Liverpool telescope helped detect the planets as they passed in front of their star.
Dr Copperwheat said: "As a robotic telescope and the largest in the world, the Liverpool telescope is very sensitive to the small, less-than-1% dips in brightness through which the planets are discovered. It's all automated, it's flexible and fast, and so is ideal for this sort of time critical work."
Nasa's Hubble Space Telescope is already being used to search for atmospheres around the planets.
Since the first confirmed exoplanet was discovered in 1992, astronomers have catalogued more than 3,500 worlds in 2,675 star systems.
Around a fifth of sun-like stars are thought to have an Earth-sized planet in their habitable zones.
Astronomers estimate there could be as many as 40 billion potentially habitable worlds in our galaxy, the Milky Way, including those orbiting red dwarfs.