Did JWST find a MARKER OF LIFE in an exoplanet atmosphere?

Correction: 02:38 K2-18b is LESS dense than Earth, not more dense. Verbal typo.

As a scientist who is not an astrophysicist, this is exactly the right level of complexity for me. Great explanation! Learned a lot

Honestly, as someone currently pursuing a degree in biochemistry with the goal of working as an astrobiologist, I think people are far too quick to dismiss how INCREDIBLE it is that we now have such excellent evidence for the existence of liquid water and a thick atmosphere on the planet's surface. If there's one thing we seem to find consistently here on Earth it's that if there is water, there is life. While this is no guaruntee, the presence of liquid water is an amazing discovery. Biosignature or not, the chances of there being life on that planet just increased exponentially! It's also great news to know a roughly earth-sized planet is capable of sustaining such conditions orbiting a red dwarf.

Fun fact: plankton is Greek for wanderer and is a synonym of planet, also a Greek word for wanderer. Plankton was first used in biology by Victor Hensen in the 19th century, to describe microscopic life that wanders the sea, because they are organisms that are unable to propel themselves against the current, thus they drift.

My cousin is an alien and lives next to K2-18b and he says there's nothing going on over there.....

But if the radius of a sphere is doubled, surely the volume would increase by a factor of 2^3 = 8. In this case, the radius seems to be 2.61 times Earth's, giving a volume of 2.61^3 = 17.78 times that of the Earth. Meanwhile, its mass is estimated at 8.63 times that of Earth. So doesn't that indicate that its density is slightly less than half that of our planet? PS: Portmanteaux should be banished!

I appreciate this clarification so much. Also the respectful way you presented it, making it clear what the authors actually presented, as opposed to what the media made of it. I’m going to look up “hycean” to see if there’s an accepted pronunciation yet.

I'd love to hear more about this "missing methane" problem you were talking about.

Excellent video. I liked your mention of Drs. Jake Taylor, Ryan MacDonald, & Prof Jayne Birkby as consultants to the analysis. This highlights the collaborative aspect of scientific research in my view. Of course, this channel always notes the authors of the publications and links their papers in the notes, which is one of my favourite features.

This was the best explanation of this exo-planet on the whole internet.

Very interesting and understandable video explanation of the K2-18b paper from the JWST observations! I've been waiting for your (inevitable) video on this paper, as you usually make very good explanatory videos after big science news from papers being published after JWST observations. For my (layman's) perspective, I really appreciate your breaking it down so that even us more "common" non-scientific folks can understand exactly what all is going on here. Great video - Thanks for this Dr. Becky!

Thank you for all you do on your great channel! I’m a high school Earth science teacher in NYC and you help me stay up-to-date on my astronomy so I can then share these exciting new discoveries with my students.

Hi, I was chatting to Maddhu after a lecture yesterday at the Cambridge IoA and he feels that their paper correctly explained that the possible presence of DMS is only tentative. It's just the media that have latched onto it. If it's presence was confirmed through further observations and modelling it would be very interesting though as it would mean biological activity or some currently unknown chemical process. By the way he pronounces Hycean the same way as you. Always look forward to watching your videos, they are great ! Kev

I really like 2 things about this video. 1. how you breakdown the NGST data and updates. This is why I am here. 2. Is how you present it.

I think that, in your discussion of why K2-18b wasn't rocky (2:23), you got the density-comparison backwards: "it is 8.63 times heavier than the earth but has a radius of only 2.6 times wider meaning that it is much denser than Earth". Since mass is proportional to the cube of the linear dimension, an Earth-like planet with a radius of 2.61 x Earth would have a mass of about 17.8 x Earth. Given that K2-18b has a mass of only 8.63 x Earth, it's mean density must be about 48% that of Earth. That said, saying that it is more Neptune-like is correct (since Neptune's mean density is about 30% of Earth's.)

This is so cool. I did an EPQ on this topic a year ago (Which Exoplanet had the Greatest Potential for life) and it’s so amazing to see JWST analysing the atmospheres. Amazing video, please keep it up. :)

As a linguist and graduate of Cambridge, I endorse your pronunciation of "hycean." That makes two of us, which is a bigger consensus that is often achieved!

Another great vid Dr Becky. Seems like Webb is getting closer to closing in on some spectacular results. There must be so much data being produced by JWST that planetary scientists must be overwhelmed.....excited but overwhelmed lol.

Great explanation . I have seen several but this one was the most elaborated and nuanced , still very comprehensible. Thank you.

As a recent subscriber, I would like to note that Dr. Becky is really fun to watch and learn from. I'm not a scientist, just an astrophysics geek with an appetite for this type of news. Learning something new is simply icing on the cake, and that's what you get by watching Dr. Becky. Bravo! Suggestion: Dr. Becky goes to Finland for a chat with Tuomas Holopainen! 😃🤘