A distant exoplanet 700 trillion miles away is captivating astronomers, and the latest findings from the James Webb Space Telescope (JWST) have reignited a major question: Are we alone in the universe?
On the latest episode of Cosmically Curious, host Patrick McNameeKing sits down with John Gianforte from the University of New Hampshire to discuss why K2-18b is making headlines. Here is their conversation.
Transcription:
Patrick McNameeKing: So, John, there's a planet called K2-18b. It's about 700 trillion miles away. Why is it in the news right now?
John Gianforte: The thing that makes this particular planet so interesting is that the star that the planet orbits is a lot smaller in size than the sun and a lot less massive, and therefore it's a much longer-lived star than the sun is. So that gives life a chance to develop on a planet that happens to be at the right distance from that star.
This planet happens to sit at an interesting distance called within the habitable zone of this star. The habitable zone is the region around a star where if a planet orbited there, and if the planet had water, it could be liquid.
Now, why this planet is in the news is because researchers using the James Webb Space Telescope have found two very interesting molecules: dimethyl sulfide and dimethyl disulfide.
These gases on Earth in Earth's atmosphere are only made by phytoplankton and bacteria living in the ocean. And because of these quantities that were measured using the James Webb Space Telescope right now, the simplistic view is: "Wow, this must be an ocean world and there must be lots of life in it."
Well, nobody's going to come out and say that without more evidence, but the evidence is overwhelming that these two gases exist in this planetary atmosphere far more than exist in Earth's atmosphere.
So that's why it's in the news, and it's so interesting.
Patrick McNameeKing: Awesome. John, thank you so much.
If you have questions about the night sky, send an email to cosmic@npr.org.
