Chris Rowan

I suddenly feel better about my 240!

I want to know how the distribution changes if you ask about their phone browser.

Sheesh - a tsunami big enough to push coral boulders 100s of m inland in the British Virgin Islands around the year 1400, likely sourced from an earthquake on the Puerto Rico Trench.

The total disrespect for their students is just mind-boggling.

⚒️ #FridayFault

Cassini proves complex chemistry in Enceladus ocean Scientists digging through data collected by the Cassini spacecraft have found new complex organic molecules spewing from Saturn’s moon Enceladus. This is a clear sign that complex chemical reactions ...

🧪⚒️ “the complex organic molecules Cassini detected…are not just a product of long exposure to space, but are readily available in Enceladus’s ocean.”

As ever - these observations show some intriguing chemistry is going on, but that isn’t necessarily life.

Apparently, they didn’t even respect him enough to put him on the movie poster?

On the other hand, LLMs do provide a good in-Universe explanation for technobabble.

Not sea glass but fragments of plastic car tail lights, indicators and brake lights, probably washed into storm drains after heavy rain, eventually making their way to the sea. #oceanplastic

I wanted to get a video of this ghost crab but every time I got close to their hole they scuttled back in, so I tried getting clever with it. I made a little sandcastle and shoved my phone into it, hit record, and walked away. Crab was VERY suspicious of this addition to their environment.

Image collected by WATSON on the Perseverance rover of "Cheyava Falls," a rock on Mars containing potential biosignatures

I've been asked a few times over the last few days what I think the chances are that the "leopard spots and poppy seeds" on Mars will turn out to be actual evidence of life. People are naturally skeptical given the history of possible signs of life on other planets. Strap in: long thread ahead...

a man with gray hair is sitting in a chair and saying `` och ... i 'm scottish . '' Alt: a man with gray hair and dressed in post-regeneration chic saying dramatically “och ... I’m Scottish.”

I also strongly feel the urge to say ‘taenite’ in a Scottish accent.

#MinCup25

Taenite is the material of protoplanetary cores - from bodies in the early days of the solar system that got big enough to differentiate, then blown apart by impacts. It’s a window into the inaccessible core of our own planet. Sorry clays, but taenite has my vote.

#MinCup25

They are interpreted as forming during one of the Neoproterozoic 'Snowball Earth' glaciations, "associated with the penetration of long-lived & extreme permafrost deep into subaerially exposed bedrock"

“Formed by cold deep & prolonged enough to suppress the geotherm” is literally extremely cool!

Series of images from a scientific paper, with the caption: Kerrera Slates. A: Bed of metadolostone with aligned ikaite pseudomorphs plunging (lower arrow) in the plane of the cleavage towards the NE, crenulation lineation in the slates is marked by upper arrow (Coin is 2 cm diameter); B: Aligned ikaite pseudomorphs in calcareous slate steeply plunging (arrow) to the NE. Pseudomorph size decreases towards lower part of exposure (Hand lens is 5 cm long); C: Aligned ikaite pseudomorphs in calcareous slates, arrow shows alignment of elongate grains (Hand lens for scale); D and E: Large elongate ikaite pseudomorphs with pyramidal terminations from the Easdale Slates.

But I think the coolest example I've found is ikaite pseudomorphs within metamorphosed Dalradian rocks in Scotland, where they appear to have grown *after* an episode of burial and metamorphism that generated a slatey cleavage.

pubs.geoscienceworld.org/gsl/jgs/arti...

#MinCup25

Heat map showing Phanerozoic distribution of glendonite (pseudomorph after the hydrated carbonate ikaite) over time (horizontal axis, from about 450 million years ago on the left to the present on the right, divided into what looks like 1 million year bins) and space (vertical axis, from 0 degrees absolute latitude on the bottom to 90 degrees at the top, 5 degree bins). Where glendonite has been identified within a particular age/latitude bin, it is shaded a light pink for a low number of recorded occurrences, green for a moderate number of recorded occurrences, and blue for a high number of recorded occurrences. The distribution of glendonite occurrences is shown to be very non-uniform over geological time, with low to intermediate counts between 40 degrees and 75 degrees latitude in the past 50 million years; largely moderate to high counts between 60 and 90 degrees latitude from about 180 to 100 million years ago; and low to intermediate counts between about 45 and 85 degrees latitude from about 300 to 240 million years ago.

Ikaite pseudomorphs found in the rock record are usually referred to as 'glendonite', and because ikaite is associated with sediments deposited in cold bottom waters, glendonite can be used as a paleoclimatic indicator.

Figure from supplementary information of www.science.org/doi/10.1126/...

Ikaite, on the other hand, is a geological ghost! Although it is metastable and does not persist in the geological record, its crystal form persists as pseudomorphs, where the replacement mineral (usually calcite) retains the shape of the mineral it is replacing.

#MinCup25

Cuprosklodowskite looks like the anthropomorphic manifestation of a deadly substance, is appropriately radioactive and (also appropriately, if rather morbidly) named after Marie Curie, and is a dead ringer for kryptonite?

No, thank you!

#MinCup25

Correct, if I’m reading correctly - it’s that they are not associated with galaxies.

So #TIL that at least some topaz forms by vapour deposition in the gas bubbles/cavities of cooling rhyolite lava flows. 😮

Others form in pegmatites, for which my appreciation is already on record 🤩

Two ultra-cool formation mechanisms means #Topaz gets my vote.

#MinCup25

A Single, ‘Naked’ Black Hole Rewrites the History of the Universe | Quanta Magazine The James Webb Space Telescope has found a lonely black hole in the early universe that’s as heavy as 50 million suns. A major discovery, the object confounds theories of the young cosmos.

🧪 Cool subtext to this cool story on the “little red dots’ - possibly primordial black holes! - dotting the early Universe is that the hopes for the James Webb telescope have been realised. It is pulling back the curtain on puzzling and unexpected things that will help us understand how we got here.

Today in “the myriad ways your children make you feel old”: when I was the age my youngest is now, the year 1999 seemed impossibly far into the future.

Now, when they tell me stories, ‘in 1999’ is a shorthand for ‘a long time ago’.

Exclusive: Google's Gemini is forcing contractors to rate AI responses outside their expertise Internal guidelines passed down from Google led to concerns that the AI model could be prone to inaccurate outputs on topics like healthcare.

Link to article in quoted excerpt:

techcrunch.com/2024/12/18/e...

Text Shot: In December, Google sent an internal guideline to its contractors working on Gemini that they were no longer allowed to “skip” prompts for lack of domain expertise, including on healthcare topics, which they were allowed to do previously, according to a TechCrunch report. Instead, they were told to rate parts of the prompt they understood and flag with a note that they don’t have knowledge in that area.

👀 pushing people to rate answers on subjects they have limited knowledge of seems almost designed to push the models towards truthiness.

https://www.theguardian.com/technology/2025/sep/11/google-gemini-ai-training-humans

Assuming they maintain integrity, the value of the samples - from known locations, with lots of in-situ data collected about their geological context - does not diminish over time.

Waiting is probably better than risking all that in a long-odds, budget constrained effort to retrieve them sooner.

Nothing but word salad from the current NASA administrator, but there are clearly no firm plans (or money) for retrieving those samples. In fairness, it’s been clear for several years that MSR was beyond NASA’s current capacity.

I wonder what the likely lifetime of the sealed sample tubes is…

Text Shot: Mr Wright defended the billions of dollars of cuts the Trump Administration has made to renewable energy subsidies. He said wind power has been subsidised for 33 years and solar for 25 years. "Isn't that enough?" the Energy Secretary asked: "You've got to be able to walk on your own after 25 to 30 years of subsidies."

So much to cringe at in this interview: "fusion on the grid in 5 years because AI"; "don't believe your geological survey about fracking, believe me"; but “renewables have had enough subsidies” is top-level chutzpah from a former fossil fuel exec.

https://www.bbc.com/news/articles/cqlz5p314z0o

spindle shaped fossil with zigzagged central axis and numerous j shaped branches with fractal-like subsidiary branches.

interpretive drawing of branching in the new inner meadow charnia arcs of primary (black) and secondary order (red) branches shown

Happy #FossilFriday from the Ediacaran of Newfoundland. For your enjoyment here is a specimen of the most common form of (as yet undescribed) #Charnia from our Inner Meadow site of #Ediacaran age in Newfoundland. It has J shaped branches and i particularly love the arcs the secondaries describe.

Arthur Holmes was, without doubt, one of the greatest geoscientists of the 20th century. His legacies include radiometric-dating of rocks, a mechanism for lateral movement of continents and continental drift, and his inspirational big fat book -'Principles of Physical Geology' (2nd edition).