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[slate]

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This is such exciting news. So we announced yesterday there are seven Earth-sized planets around TRAPPIST-1. 

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That’s a star just 40 light-years away, so it is very close to our solar system and its got a mini one of its own. 

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Three of those planets – three of those seven Earth-sized planets – are in that star’s habitable zone, so if they have a surface liquid water could exist there. 

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But this is a very alien solar system. If you compressed it into our own solar system it would fit within the orbit of Mercury. 

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So, it is a very tight system, TRAPPIST-1, compared to our own. So, it is really interesting for scientists to study and try and understand.

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[laughing]

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I don’t think we need to be worried about that just yet. This is a really exciting discovery though for scientists because we are able to look at these planets. 

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These planets are what we call transiting. So, they pass in front of their star and this blocks a small amount of the light. Now the TRAPPIST-1 system like you said has seven Earth-sized planets

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and three are in the habitable zone, so it is something new for us as scientists to be looking at and being able to study with our telescopes.

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So we don’t know that just yet, but if these planets actually have a surface then they are at the right temperature that liquid water could exist on their surface. And that is really exciting.

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This is the best opportunity scientists have to study this kind of planet outside of our solar system, outside of our Earth. And that’s really, really interesting.

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So, if you look at the TRAPPIST-1 system it would actually fit within the orbit of Mercury in our own solar system so it is very compact and very different.

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But, the difference is that the star is also very small and cold, so these planets can exist at the nice Earth-like temperature very close to their star.

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[laughing]

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So it is about 40 light-years away. So it takes light, which is the fastest thing in our universe to – 40 years to get there.

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So with current technology it is going to take us a little bit longer. But what we can do is we can look at these planets’ atmospheres by using the transiting technique, which you can see there on your screen.

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And that is actually looking at the amount of light that is changing as the planet passes in front of the star.

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And we can actually look at the colors of that light as it shines through those planet’s atmospheres, so light shining through the Earth’s atmosphere and you can see it from the beautiful pictures from the International Space Station.

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And we – we’re actually seeing the light that’s coming through those planets, those Earth-sized planet atmospheres before reaching our telescopes, like the Hubble Space Telescope, and being able to work out what their atmospheres might be like.

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So that’s the next step for scientists with that system.

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So there are loads of things we can do now. We’re using the space telescopes that we have here at NASA – so the Hubble Space Telescope – which has been looking at planets for the past five to ten years.

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And this is exciting because Hubble’s been in space for 26 years and exoplanets weren’t even a thing then. So planets outside of our solar system were discovered in 1995.

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So, we’re using Hubble which was upgraded to look at these planets and their atmospheres.

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So it is really, really exciting that we are able to use the technology that we have to look at something brand new.

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Yeah, if you want to know anything about this system, this discovery and others go to nasa.gov/exoplanets to find out everything you want to know about what NASA’s doing with exoplanets these days.