@jjfplanet.bsky.social Missed being at OWL this year, but found a facsimile while starting my postdoc in Ireland

Tomorrow at 10am (EDT) I'll be defending my thesis focusing on getting a precise and accurate parameters of the coldest brown dwarfs with JWST. If you'd like to join virtually, DM me for the zoom link!

About that new paper on K2-18b, which headlines with "Scientists hail ‘strongest evidence’ so far for life beyond our solar system," evidently prodded by a Cambridge U. press release. arxiv.org/pdf/2504.12267 . It's not actually any kind of evidence for life, and here I'll give my take on the paper.

Artist's impression of the exoplanet K2-18b. Credit: A. Smith, University of Cambridge.

𝗡𝗼, 𝗮 𝗯𝗶𝗼𝘀𝗶𝗴𝗻𝗮𝘁𝘂𝗿𝗲 𝘄𝗮𝘀 𝗻𝗼𝘁 𝗷𝘂𝘀𝘁 𝗱𝗲𝘁𝗲𝗰𝘁𝗲𝗱 𝗶𝗻 𝗞𝟮-𝟭𝟴𝗯'𝘀 𝗮𝘁𝗺𝗼𝘀𝗽𝗵𝗲𝗿𝗲.

K2-18b is back in the news, now with a bold claim that biosignature molecules (DMS and/or DMDS) have been 'detected at 3σ'.

Most exoplanet astronomers are extremely sceptical about these claims, let's see why (1/n).

🔭🧪🪐 #exoplanet

They ignore so many other explanations, including the fact that this likely isn't even a hycean world, and ignore the huge systematic uncertainties present in this analysis method. That's true even if your data is good, which theirs is not. The press should not give them the benefit of the doubt.

As an astronomer who studied cold exosolar atmosphere, this paper is infuriating, especially since these researchers already tried to claim a DMS detection on similarly shaky grounds and were rightly clowned on by the rest of the field for their bad science.

With a baby on the way in ~2 months, there are still people in my astronomy department who don't know because it hasn't come up. At this point, do I just wait it out and show up to colloquium with a whole baby?

One of my professors has the quote "There is no expedient to which a person will not resort to avoid the real labor of thinking" as his email sign off. I don't think LLM's have changed the nature of people, but it certainly has lowered the barrier to avoiding "the real labor of thinking".

Two huge firsts! It was a pleasure to work on this paper and be a part of history. So much more to learn from these two molecules.

I'd be interested in being added if it's not too much trouble.