Scientists have discovered seven planets orbiting around a star – and all seven could potentially have liquid water and life on their surface.
They are all in what scientists call the habitable zone, which is the area around a star where liquid water could exist on a planet. This is also known as the Goldilocks zone, because it’s neither too hot nor too cold.
The planets are all about the same size as Earth, but orbit much closer to their star, TRAPPIST-1, than the planets in our solar system. But they don’t get fried because TRAPPIST-1 is only 0.05% of the size of our sun.
The planets are so close together that if you were on the surface of one of them and looked up, some of the other planets would look bigger than our moon. You could even see features like clouds or continents on them!
It’s thought that the planets are all tidally locked to their star. This means that the same face of each planet constantly faces the star, in the same way that we only ever see one side of our moon.
The researchers say that the TRAPPIST-1 system is close to us, but that’s only in astronomical terms. It’s actually about 40 light years away, or 378 trillion kilometres (235 trillion miles)!
“Answering the question ‘are we alone’ is a top science priority,” said NASA’s Thomas Zurbuchen. “Finding so many planets like these for the first time in the habitable zone is a remarkable step forward toward that goal.”