In May last year, Michael Gillon of Université de Liège, Belgium, and a number of colleagues found three of the exoplanets in the Aquarius constellation orbiting an ultracool dwarf star called TRAPPIST-1 around 39 light years from our own solar system.
Solar system with seven Earth-like planets has been discovered
It could be the best chance yet of finding life on other worlds - seven Earth-sized planets, some likely with oceans, have been found orbiting a dwarf star. /div>
The find will have astronomers and stargazers excited, with the details of the spectacular discovery made public in a NASA announcement on Thursday morning (NZ time).
Research co-author Amaury Triaud says the small amount of energy coming from the star is a lot weaker than our Sun, meaning the planets need to be far closer than in our Solar System for surface water to exist.
"Fortunately, it seems that this kind of compact configuration is just what we see around TRAPPIST-1," he says.
-TRAPPIST-1 is just 8 percent the size of our Sun and is marginally bigger than Jupiter.
-TRAPPIST-1b, c and d are probably too hot to support water, except possibly in small parts, climate models suggests.
-TRAPPIST-1e, f and g are in the 'Goldilocks zone' meaning they're not too hot or cold to have oceans.
-TRAPPIST-1h's orbital distance is unconfirmed, but is likely to be too cold and too far to hold liquid water.
The findings will prove important for astronomers, with new generations of telescopes such as the European Southern Observatory's Extremely Large Telescope and the James Webb Space Telescope able to search for signs of water.