But stars like these are cooler than the sun, which means the habitable zone – the orbital band where temperatures are mild enough to allow liquid surface water – is much closer to GJ 887 in comparison to the Earth’s distance from the Sun.

For the planets orbiting GJ 887, half of the planets would be in perpetual daytime and the other half in perpetual nighttime

The discovery was made by an international team of astronomers, including researchers from the University of Hertfordshire, The Open University and Queen Mary University of London.

But the researchers say GJ 887 is less active than other red dwarfs, so the newly discovered worlds may be spared from strong stellar winds – outflowing material from the star which can erode a planet’s atmosphere.

For the planets orbiting GJ 887, half of the planets would be in perpetual daytime and the other half in perpetual nighttime.

Writing in a related comment piece, Melvyn Davies, professor of astronomy at Lund University in Sweden – who was not involved in the research, said: “If further observations confirm the presence of the third planet in the habitable zone, then GJ 887 could become one of the most studied planetary systems in the solar neighbourhood.”