Geoff 🏴󠁧󠁢󠁳󠁣󠁴󠁿

Geek: Photography, physics, comedy, computers, science fiction, astronomy, aviation, books, glass, whisky, maths, cosmology, human survival mechanisms, rock/bass, whimsy. Follower voted colour #295F78

https://thegeoff.net

~ School science technician
~ Science/Art collaboration
~ Cats: Cassie & Tia
~ Found first 3 books in π
~ Hacker: The good kind.

Personal account..

Where?: Scotland, Highlands
Pronouns: He/him, or whatever you prefer.
Flickr: https://www.flickr.com/photos/_thegeoff/
Web:: https://thegeoff.net

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Last Notes

2026-06-22 20:21:23 UTC

Some international confusion on how the position of Prime Minister works in the UK:
It's not a constitutional position, other than by habit*. The Monarch is, technically, the ruler. However, after a certain amount of awkwardness surrounding our first two King Charles's, the monarch has chosen, voluntarily**, to temporarily deputise some powers to an MP who can demonstrate they're really quite popular.
*We don't have a written constitution
**On the basis they keep the thing the crown goes on

2026-04-17 19:59:45 UTC

Doing my first full watch-through of #StargateSG1. Spotted Dwight "Howling Mad Murdoch", "Reginald Barclay" Schultz the moment I heard his voice, brilliant :)
https://files.mastodon.social/media_attachments/files/116/421/816/374/905/035/original/ce11e74857451ac0.png

2026-04-16 20:37:51 UTC

I made the mould for two of these :)
(Yup, they're hand blown, but for the really complex ones the specific detail requires making a bottle of roughly the right shape/volume and then blowing it into a mould, before a LOT of finishing.)
And yes, silly money, but the ones I did were for charity, so there's that.
https://www.youtube.com/watch?v=iMd5TOeE604

2026-04-15 22:31:46 UTC

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This is prized in some circles as once you dry it out it makes some of the best firelighting material in the world. Get it glowing and you can pack it away carefully, walk for 12 hours, unpack it and blow on it, and have another fire.

2026-04-15 22:26:10 UTC

There was a wooden framed couch in my uncle's holiday cottage we visited as kids in the 80s He donated it to me and J when we moved into an unfurnished house in 2010. Already rickety.
In 2016 we bought a bigger couch, I sanded it all back, yacht varnished it, turned it into a garden couch. Bit dodgy though.
It's finally succumbing to the elements. But one of my favourite fungi, Fomes fomentarius, or the hoof fungus, has taken hold.
https://files.mastodon.social/media_attachments/files/116/411/061/716/845/238/original/afba936e1f90195e.jpg

2026-04-10 23:44:56 UTC

GARGH! NASA making the same mistake as the Scottish qualifications people, spacecraft don't generally heat up on re-entry due to "friction", it's down to adiabatic compression mostly, squeeze a gas and it gets hot. Squeeze it more and it turns to a plasma. Squeeze that even more and it starts giving off high energy photons.
That's not friction.

2026-04-06 20:48:05 UTC

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Funnily enough, a popular technique in archaeological survey. Watch out for the "large rectilinear shadow" ;)

2026-04-06 20:46:02 UTC

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I stand corrected, mission control just said the "terminator looks very alien". Lovely description from the crew about how now they're seeing the far side "there's no part of the terminator that just doesn't look impossibly rugged". The far side is far more cratered as it hasn't had Earth as a shield.

2026-04-06 20:40:42 UTC

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Crew free to take photos of whatever they want, and both the photographers have gone with The Terminator. Seriously, no thought for Alien, straight for The Terminator.
(I jest, for anyone who doesn't know, the terminator in this context is the bright/dark bit of the lunar sphere, great for looking at stuff in high relief.)

2026-04-06 20:33:11 UTC

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No idea why, but I have a sudden urge to buy a Nikon 80-400mm zoom lens....
#Artemis

2026-04-06 20:21:57 UTC

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We're not so used to big time delays in communications these days, but there's no getting around it at this distance. The 2.6s delay between here, the Moon, and back, is noticeable. They're noticeably far away in terms of the speed of light. #Artemis

2026-04-06 19:53:55 UTC

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Toilet continues to be an issue, limits reached for the moment, pee bags etc to be used. But to be fair, this is the first translunar mission to *have* a toilet, and it's generally recognised that the major engineering issues in spaceflight are plumbing, humans, and human plumbing. #Artemis

2026-04-06 19:30:00 UTC

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Crew reporting that looking at the Moon in full sunlight, and switching back to a mostly dimmed cabin (to prevent light leakage impacting lunar photography) is "proving challenging" in terms of adapting eyesight.
An earlier solution was a single eyepatch, keep one eye dark adapted. #Artemis #SpacePirates

2026-04-06 18:26:16 UTC

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"Amaze, amaze, amaze" from mission control to #Artemis, nice #ProjectHailMary reference :)

2026-04-06 18:02:59 UTC

Carroll Crater, nice 🥰
#Artemis

2026-04-06 11:06:46 UTC

If I was on Artemis I'd spend the 40 minute radio blackout rigging all the clocks, logs, instrumentts etc to show that 6 hours had passed, then refuse to comment on what I'd seen on the far side.
This is probably why I'm not allowed on the Artemis.

2026-04-05 18:10:10 UTC

The Ender 3 Pro 3D printer I bought almost exactly 6 years ago (lockdown was the nudge I needed!) has started extruding erratically. Couldn't withdraw filament. Turns out the old advice still works: cranked the temp up briefly, boom. Can't be stuck if it's a liquid.

2026-04-04 18:56:22 UTC

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You've oddly reminded me of a spoof "He-Man" theme we'd song as kids:
"I have the power
To lift up a flower
In a hour or two..."
Assume the distance is floor to waist and we can even do some physics 🤣

2026-04-04 18:07:06 UTC

Grr. Manly welding gauntlets, for manly activities, like welding. Note too that they're not gloves. They're *gauntlets*, cos this is fabric armour.
Wait...have we been wearing Powerpuff Girls (or similar?) gloves with an extra felt layer all along?! I've long suspected the welding/Brony overlap is strong 🤣
https://files.mastodon.social/media_attachments/files/116/347/747/805/452/166/original/79ec80c802755a58.jpg
https://files.mastodon.social/media_attachments/files/116/347/748/075/201/949/original/1cfd2c29b7061a41.jpg

2026-04-03 20:30:23 UTC

First day of the school holidays. So firing the tandoor up as per tradition. A couple of aubergines as it got all flamey coming up to temp (so baba ganoush, the only acceptable use of an aubergine in my book), then chicken tikka skewers followed by chicken legs, thighs, wings as it cooled a bit. Plus kachumba salad thing and shop bought naan, but done in the tandoor. Homemade naan done properly remains an objective, but damn is that an aquired skill.
https://files.mastodon.social/media_attachments/files/116/342/657/374/239/417/original/13240480000b0eee.jpg

2026-03-31 21:12:51 UTC

Cracked open the cyanotype stuff as an end of term thing for the 6th years (~18yrs). "Wait, so this is like science AND art?"
Well isn't everything ;)
I got a nice effect from a translucent plastic pipette, 6th years have been running around looking for feathers and making cool stuff. Luckily caught a couple of non-science photography students taking shots and gave them a couple of sheets with instructions too.
No pics till I clear copyright with the cyanophotographers...

2026-03-29 00:27:11 UTC

Today is the anniversary of me opening a bookshop after the clocks changed, and spending so much time responding to people banging on the door to ask why we're late opening ("we're not, you're an hour ahead") that we were late opening.
Yup, put up a sign, just not soon enough. Still, a world where people bang on bookshop doors at 8.30am is a good one.

2026-03-28 01:52:25 UTC

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I'm totally suggesting dumpling in the stew - suet type, litte glorious balls that fluff up and go crispy

2026-03-28 01:39:57 UTC

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Are you of a culture that does dumplings? If not, I have an epiphany for you.

2026-03-26 22:08:42 UTC

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See also UK slang: Trump (v/n): A fart/flatulence, or the act of creating one.

2026-03-26 01:00:37 UTC

Guess the reason for the photo?
https://files.mastodon.social/media_attachments/files/116/292/765/017/186/794/original/5cec99862cf90197.jpg

2026-03-25 21:53:29 UTC

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Lovely way of putting it! I did a displacement demo earlier this week, aluminium foil in copper sulphate solution. Bugger all happens, of course, then I squirt in a little hydrochloric. And obviously drop a match in for pretty lights.
Titanium skinned aircraft like the SR71 had a similar issue with, IIRC, scratches from tools containing cobalt? Almost like the Gallium/Aluminium interaction?

2026-03-25 18:36:17 UTC

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Dad's PhD was on stress corrosion cracking in marine environments, he ended up working on the metallurgy of submarines, aircraft, climbing kit and oil rigs. I can listen to him talk about it for hours. Takeaway advice: don't clean your safety critical aluminium with steel wool.

2026-03-19 21:30:37 UTC

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Hey, that happens all the time. When I (an atheist) first saw The Matrix I assumed it was mainly a Christ allegory, as well as being e great bit of SF. Later turned out to be more a trans allegory. We all read our own things into stuff, and the best pieces of work allow many interpretations.
Grace being a single surviving human of a trinity sacrificed to save humanity? Meh, yeah, maybe Weir did mean that, among other things. Good storytelling.

2026-03-19 21:20:07 UTC

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Gave my copy to a friend, so I can't check it right now, but "Project Hail Mary" by Andy Weir is a good bet ;)

2026-03-19 21:16:10 UTC

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Exactly. Not every person who throws a Hail Mary pass is a Christian, but that's still the etymology.

2026-03-19 21:06:40 UTC

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Yes, it absolutely is a religious reference. No, that does not mean the book is a Christian allegory. It's a piece of hard science fiction that acknowledges our current worldwide culture and society, which includes religions. But yes, the reference is specifically that Mary, otherwise the gag with the main character's name doesn't work.

2026-03-19 20:54:20 UTC

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Hail Mary is literally full of Grace, the gag is right there.
The book also had other missions, by other international collaborations, that drew similar names from other religions/philosophies

2026-03-19 18:06:41 UTC

"And some people say 'These people, they're not even trying to be British. They come here, they bring their own culture, their food, speak their own language, and try to take over the whole bloody place.'
Dunno. Sounds pretty British to me."
~Trevor Noah
😂

2026-03-19 17:21:59 UTC

Ladybirds are coming out of hibernation and there's a whole not-entirely-PG-rated party going on.
https://files.mastodon.social/media_attachments/files/116/256/982/847/310/489/original/87b0c0468cbf049f.jpg
https://files.mastodon.social/media_attachments/files/116/256/983/199/415/323/original/2ade666bce763c2c.jpg

2026-03-17 19:53:36 UTC

In case you missed it, new particle just dropped. The LHC has confirmed (and in ridiculous accuracy) the existence of a heavier version of the proton.
A proton is made of 3 quarks, up/up/down. This new particle is made of charm/charm/down, where the charm quark is basically the same as the up, just heavier.
So not groundbreaking like finding supersymmetric particles, but still cool. Further confirmation that the standard model of particle physics is reasonable.
https://home.cern/news/news/physics/lhcb-collaboration-discovers-new-proton-particle

2026-03-17 18:42:07 UTC

Chatting to a student who happened to be in the same screening of #ProjectHailMary as me. She was asking how much of the science was real. (Long answer short, enough to make it a very respectable bit of "hard" science fiction.)
We established that if Rocky's species did the Scottish physics course they've done Nat5 and some, but not all, of Higher. Their Craft, Design & Technology courses are significantly more advanced though.

2026-03-14 21:38:40 UTC

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Stuff from the book I wish they'd done in more detail: astrophage biophysics, Stratt's virtual immunity from any action, the building of common terms between Grace & Rocky, particularly the Iron/26 gag.
But it's a fairly long film anyway, and modern films tend to too long for my taste, I think they distilled the important stuff for the story well.
But if you watch it and like it, and haven't read the book, READ THE BOOK! 😎

2026-03-14 21:33:26 UTC

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Possible error - loading a microbiology centrifuge with 2 tubes, both next to each other rather than balanced. But seeing the abuse the handheld mass spectrometer gets, the lab kit on the ship is pretty robust.
What looks like an error but isn't: Travel time given by the ship's computer for a ~12 lightyear journey is given as 4 and a bit years. But as Dr Becky notes in her interviews, that's realistic time dilation. Threw me slightly while watching as I briefly tried doing sums.

2026-03-14 19:52:26 UTC

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Also, pretty good film to take kids to.

2026-03-14 19:51:38 UTC

#ProjectHailMary - skipped over some aspects, lingered a bit long on others, but generally a pretty faithful adaptation. Very pretty, and got the humour.

2026-03-13 18:54:08 UTC

[@Theorem_Poem](https://mstdn.social/@Theorem_Poem ) Don't know if I mentioned it before, but tonight I finished the jar of garam masala that J bought in Iceland when she was performing there! There's got to be some sort of remotest-spice-sold record?
https://files.mastodon.social/media_attachments/files/116/223/382/077/803/702/original/f39d9d56ada8157a.jpg

2026-03-13 16:01:06 UTC

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Here's the Forbidden Chocolate mostly dried out.
https://files.mastodon.social/media_attachments/files/116/222/688/588/986/588/original/bb9648fbc0b62bff.jpg
https://files.mastodon.social/media_attachments/files/116/222/688/843/569/503/original/d4734d33ec37191f.jpg

2026-03-12 22:44:07 UTC

Less than two days to go before I see Project Hail Mary. Not been this excited about a film in a long, long time, I normally wait for it to come out on DVD or Netflix or whatever. Saw a review recently which described it as "weirdly childish"....guessing they hadn't read the book, and that's encouraging in terms of nailing the tone.

2026-03-11 23:09:43 UTC

Colleague in one of my 3D printing jobs wanted to recreate a Simpsons prop in real life as a present for a friend. I just did the cane (the detail is IMMACULATE), other colleagues volunteered their time and skills for other bits.
https://files.mastodon.social/media_attachments/files/116/213/046/489/580/442/original/dd71a873876db35c.jpg
https://files.mastodon.social/media_attachments/files/116/213/057/732/223/871/original/ad93edf2ecbefe8a.png

2026-03-11 21:39:09 UTC

Must not eat forbidden chocolate...
(Disposing of some past-its-best iron iii nitrate with sodium carbonate, the brown precipitate is iron oxide...rust...that can go in the bin, the rest can go down the drain.)
https://files.mastodon.social/media_attachments/files/116/212/699/791/009/461/original/82fd7229a2d662f6.jpg

2026-03-10 17:17:30 UTC

There used to be a startup where you could buy intentionally thermally inefficient computers to install in your house as radiators. They were networked, and the company would sell off distributed computing power and split the money with you, essentially subsidising your domestic heating.
This should be the model for LLM/ML, no huge data centres, just very cheap electric heating for households. But that won't happen in the current bubble because investment is locked in to a different model.

2026-03-02 21:16:08 UTC

RE: https://bildung.social/@phyphox/116159553496495606
Brilliant, a similar approach to my recent "can you track the concentration of a solution with the pitch you get pinging the beaker" idea 😎👍
#note1w4p…m6cu

2026-02-28 00:36:47 UTC

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But personally I think we should expose kids to science "way beyond their level" far more. I remember a spectroscopy image in a Heather Couper book when I was maybe 8 years old. Fascinated me enough to go into astrophysics and I finally understood it at 18.

2026-02-28 00:18:57 UTC

At an IoP "Girls In Physics" event recently. Multiple presentations for our S1 group (maybe 12yrs) which were technically far beyond them in terms of curriculum but still fun. PhD students from Glasgow did themselves proud with a fun polarised light workshop, and Dundee Uni had some nice exoplanet/spectroscopy stuff on the go.
I got to yell "Oh, look, spectrum!" on the bus trip home 😉
https://files.mastodon.social/media_attachments/files/116/145/382/063/416/106/original/2c5025e0d976538c.jpg

2026-02-23 21:27:51 UTC

Made some ferrofluid at work today. Give it a day to soak, and given enough time I might get some cool video tomorrow. Fun exercise if you have access to a few grams of laser printer toner, vegetable oil, and a neodimium magnet.

2026-02-22 20:32:51 UTC

Some fun rocks on the Easter Ross coast. Some of this is Old Red Sandstone, a pretty old type. There's differential erosion on the go, and the potholes/honeycomb structure is a result of wave action. Any small dimple is more likely to catch a grain of sand or pebble, which rolls around grinding the dimple deeper, letting it catch a larger stone, grinding more, etc etc.
https://files.mastodon.social/media_attachments/files/116/116/165/305/950/032/original/17a3702a874fe4a9.jpg
https://files.mastodon.social/media_attachments/files/116/116/166/665/728/435/original/c0b69429323ef3cc.jpg
https://files.mastodon.social/media_attachments/files/116/116/168/179/811/460/original/b81a4e5818f42740.jpg
https://files.mastodon.social/media_attachments/files/116/116/169/446/869/805/original/fa187abdbb526dbf.jpg

2026-02-21 21:34:10 UTC

It's time for the webring (or similar) to make a comeback. Do you have your own science/tech/related blog etc? Give me a shout, I'll add yours to thegeoff.net if it fits. Ideally self-hosted, but hey, practicalities. Particularly just folk messing about on their own projects, not already-popular stuff.

2026-02-18 19:14:27 UTC

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But that aside, it's incredible tech, and the advances in my lifetime are stunning. Just for the basic kit, which would give a fairly reliable result on "suspect DNA" v sample, or paternity tests in fairly unrelated subjects (e.g. it's not two brothers being tested as the father) we're looking at under £2k for the kit and reasonably cheap consumables.
We've got the kit at school, never been used as it's more a specialist student project. But good to have an actual run-through on using it.

2026-02-18 19:03:22 UTC

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To their credit, they covered the fact that this world-changing, Nobel prize winning tech was developed by somebody who was "high". They left it at that.
Nope, not having a good idea after smoking a joint, which is surprisingly common in science and maths, but a pretty big dose of LSD and then going for a drive. Interesting character...
https://www.youtube.com/watch?v=zaXKQ70q4KQ

2026-02-18 18:47:25 UTC

Fun "Techiebears Picnic" today, one of our too-rare school science technician meet-ups. Somebody from Timstar, one of our main suppliers, ran a PCR and electrophoresis course (basically DNA fingerprinting), very handy for me being a physicist by training and trying to brush-up on my biology.

2026-02-13 17:08:21 UTC

One of my chemistry students made drugs. Aspirin, in this case. They confirmed they'd nailed it with a very accurate melting point measurement and then some thin layer chromatography. Yield was a little low, but hey, first go using high school kit. I made them a little souvenir, 0.06g of it in a tiny handmade phial.
https://files.mastodon.social/media_attachments/files/116/064/409/903/328/997/original/3d42c434fa02bdfb.jpg

2026-02-04 18:39:08 UTC

Fun one from today: student was measuring copper content in a penny by dissolving it in conc nitric acid and doing science titrations on it. I'm left with remainder of the copper/acid to dispose of (fair enough, my job and all). So I neutralise it with bicarb, filter precipitate off for the bin, filtrate can go down the sink.
But what are these tiny blue/green crystals forming overnight in the (water based) filtrate?
(Awaits obligatory AS reference ;)
https://files.mastodon.social/media_attachments/files/116/013/810/152/691/661/original/6706ad4eada88201.jpg

2026-02-02 18:08:39 UTC

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HA! I'm almost exactly halfway through too, but was convinced it was a useful enough video already. The advanced proofs hinted at do seem to involve your brain turning inside out though, we'll see!

2026-02-02 18:05:01 UTC

One of my favourite mathematical theorems is "The Hairy Ball Theorem". Partly cos the name is funny, which makes students curious, partly because an upshot is that you can prove (with caveats) that there is always somewhere on the Earth with no wind, and partly that it's simple enough for me, undergrad-maths-ish, to explain it to high-school students. Plus it's vector fields, something they will meet and sounds scary without this kind of intro.
https://www.youtube.com/watch?v=BHdbsHFs2P0

2026-01-29 18:33:14 UTC

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The actual tandoor is full of cracks, as you say, hey, no problem, it breaths! Problem with the lid cracking is if/when it falls in it risks totally smashing the rest of the oven.

2026-01-29 18:29:45 UTC

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Currently using terracotta, on my third and that's about to go! Maybe I'm buying cheap stuff, it is just a plantpot dish with a hole in it. Borosilicate glass did cross my mind....plus it'd look really cool.

2026-01-29 17:55:31 UTC

Niche physics question: I keep shattering ceramic lids on the tandoor, thinking about an aluminium one. In terms of heat loss from inside the oven, over a scale of hours, does the thickness actually matter? I'm thinking thicker won't cool down as much when it's removed, so won't need to be heated up again?

2026-01-27 18:37:57 UTC

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The sgian dubh (Scots Gaelic, "skee-an doo", literally "black knife" or "hidden knife") is traditionally worn with Scots dress, tucked into a knee-length sock. Traditionally used like a penknife for just being handy, although could be for defence at a push. UK knife laws have a specific exception allowing us to wear them as part of the dress in public, alongside Sikhs and the Kirpan.

2026-01-27 18:29:39 UTC

Me, walking into lab where teacher and 6th years (~17/18yrs) are talking. They stop.
Teacher: "OK, Geoff, do YOU believe in ghosts?"
Me: "Erm...I believe people *experience* them..."
Teacher: "But what about our energy, what makes us 'us'? Where does that go?"
Me: "What units are you measuring this energy in? How are you measuring it?"
Student, deadpan: "Ghost energy is obviously measured in Ghouls."
No notes, perfect, told student they should write next Ghostbusters film.

2026-01-27 18:16:21 UTC

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Haggis (which I've heard claimed as an Indian origin dish too!)
Sheep's heart, lung and liver, finely diced and mixed with barley, oatmeal and spices (mostly black pepper), then traditionally sealed in the stomach and boiled...although this one is a more modern version in a synthetic casing. Actually very nice, spicy and savoury. Common fast food in chip shops, formed into a sausage shape, battered and deep-fried.

2026-01-25 17:27:25 UTC

Dinner on the go, with the correct serving utensil.
"I think most Scottish cuisine is based on a dare."
~Mike Myers
https://files.mastodon.social/media_attachments/files/115/956/858/602/098/586/original/b5038476f7f59122.jpg

2026-01-24 22:27:55 UTC

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And bloody hell, whoever made this video for their Sad But True cover deserves all the awards. https://www.youtube.com/watch?v=QpxA_ZxGX_M

2026-01-24 22:20:52 UTC

Didn't realise The HU had covered Iron Maiden's The Trooper.....in Mongolian....with some awesome morin khuur (bowed two-string bass thing) doing some fabulous wailing guitar stand-in.
https://www.youtube.com/watch?v=2WrvFUZgHro

2026-01-21 16:41:14 UTC

Found an ice-spike at work! Apparently more common with distilled water, which we do sometimes use for ice, but this is just tap. Although Scottish tapwater is very soft anyway.
https://files.mastodon.social/media_attachments/files/115/934/071/319/216/529/original/de8b50d1944a4c76.jpg

2026-01-19 22:42:58 UTC

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The one timelapse I got to work nicely. (I really need to learn that function in daylight...)
#Aurora #Scotland #Highlands #Timelapse
https://files.mastodon.social/media_attachments/files/115/924/175/057/503/035/original/093016d70e6bf743.mp4

2026-01-19 22:40:33 UTC

All kicking off here, and some of this is looking *south*. #Aurora #Scotland #Highlands (Straight off the camera, no editing other than to scale down to meet upload limits)
https://files.mastodon.social/media_attachments/files/115/924/157/118/013/946/original/02d85865facdb36e.jpeg
https://files.mastodon.social/media_attachments/files/115/924/157/437/359/756/original/1df48e5a3b49251e.jpeg
https://files.mastodon.social/media_attachments/files/115/924/157/856/693/656/original/b217ff0622ee9211.jpeg
https://files.mastodon.social/media_attachments/files/115/924/158/309/951/927/original/f95cc935a3594dbf.jpeg

2026-01-17 21:08:02 UTC

Question on #physics, specifically Einstein's equivalence principle that you can't tell if you're in a 1g gravitational field or undergoing 1g acceleration in a rocket or similar:
1: Most rocket accelerations etc are linear. Hold your arms out and drop two coins, they land *directly* "beneath" your hands.
2: You can't have a perfectly linear gravitational field, as far as I know? Drop two coins on Earth, they both land *slightly* closer to your feet because it's a radial field.

2026-01-16 18:40:59 UTC

This whole Nobel prize thing sums Trump up. He just doesn't get that it's an award (OK, sometimes controversially) for something you've done. He thinks it is something you can own, buy, have. He's laughable. And he has nukes, but first and foremost he's laughable.

2026-01-14 21:33:17 UTC

[@Theorem_Poem](https://mstdn.social/@Theorem_Poem ) Been looking at whether it's even possible to have a go at learning a little of Indian raga stuff on a western instrument. Sarod is fretless, and I've got a fretless bass, so that's a start. But the strings are wound, so running a nail sounds *screechy*.
What does work better is the US country inspired "bottleneck", but I can't target individual strings.
This is fun though :)
https://youtu.be/pjnEpIoQnkg

2026-01-14 16:54:37 UTC

Student doing a chemistry project based on a fairly old protocol they found online. So old that it has instructions for making your own capillary tube - these days schools just tend to buy them in bulk. But hey, they had a prefecting period with me today, so why not?! I went first, as I've never done it either, to see if there were any tricks. Meh, not bad, but a bit squiggly. Student has a go, absolutely nails it 😂
Both delighted the writeup can include "made my own custom glassware".

2026-01-07 17:05:47 UTC

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Yeah, if we can pull 240V at 10A it drops to about 2 months. But in reality there's going to be a lot of losses, and it's not a linear charge curve (the last few megawatts will take ages), but maybe under a year? Ideally we need it under 9 months so Marty can't father himself and end the universe by meeting the baby?

2026-01-07 16:53:23 UTC

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The US does have 240V to the home these days I think, as two phases that get split at the distribution board? 1955 I don't know about.

2026-01-07 16:24:28 UTC

#Physics / #SciFi question: In Back To The Future could Doc Brown have built a capacitor bank from everyday materials in 1955 that would be able to deliver 1.21GW just by charging from a domestic power supply (rectified)? I'm estimating you'd need about 250kF? You're allowed to consider everything as sacrificial, a "one-shot" output.

2026-01-07 12:16:42 UTC

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And if it's the one I'm thinking of, there's a nice orbital mechanics punchline.

2026-01-04 17:22:11 UTC

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Doesn't surprise me, the rain is so heavy it's visceral. Then add a few bass thunder notes on top! This kind of thing? https://www.youtube.com/watch?v=DMGrjpDLT30

2026-01-04 17:15:16 UTC

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Oh, and thunderstorms. Rare here, maybe one or two a year, but India/Nepal put on some stunning shows.

2026-01-04 17:14:10 UTC

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I've done 3 months (well, northern India and Nepal combined), while the daylight swings are quite boring you do have some interesting stuff going on with the whole monsoon thing.

2026-01-04 17:11:29 UTC

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What was your complaint 6 months ago? "Does it never get dark in your country?" 😜

2026-01-04 17:09:13 UTC

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It's Scotland, if you don't like the weather just wait a few hours ;)
(Or, given the forecast, at least a week!)

2026-01-04 17:07:18 UTC

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I mean, subzero temps aren't going to stop something that goes to 400C, but the amount of wet stuff falling from the sky will still try to shatter stuff.

2026-01-04 16:35:54 UTC

The #Highland artist continues her project. The thermal blanket is the basis of the project. The survival suit is coincidental.
https://files.mastodon.social/media_attachments/files/115/837/791/377/002/204/original/605590d5d078e0a8.jpeg

2026-01-04 16:31:07 UTC

#WillItTandoor ? Maybe not today...
https://files.mastodon.social/media_attachments/files/115/837/772/452/352/095/original/9663261e0a1dd0ae.jpeg

2025-12-23 19:34:26 UTC

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After using an eReader for a while I found myself looking at the top right corner of an open (paper) book to check the time.

2025-12-23 17:49:11 UTC

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Neither I or the physics teacher actually know how the vertical waves worked, it was more/less yellow waves moving upwards, which probably means a subtle change in the fuel/air ratio? Need to get it on video with a high frame rate.

2025-12-23 17:43:58 UTC

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I encouraged students to have a go with the Flaming Laser Bass, even if they couldn't play an instrument, just twang the strings and see the flames leap, which I can personally tell you is quite a visceral experience. A few did. A couple played other instruments (fiddle) and picked it up really quickly, picking out a tune within a minute or two. One actually played bass, and was better than me (hobby-learning for ~5 years), they managed to get vertical waves on a per-flame basis (vibrato?)

2025-12-23 16:40:51 UTC

Things we proved in the physics lab on the last day of school:
You can feed the signal from an electric bass to a HeNe laser, bounce it across the lab via five mirrors, pick up the signal and feed it to a Rubens tube so you can remotely "play" leaping flames. This is Very Science and not remotely Very Cool.
A class of third years now understand that w̶h̶e̶n̶ if they are carrying out a heist then they need to use minimal amounts of laser detection powder, as it will still attenuate the signal.

2025-12-20 23:24:10 UTC

Microsoft email asking me to verify my age on an account I registered 20 years ago to prove I'm over 18.
You know what? I don't actually need Xbox Live. Certainly don't need to have my driving licence on the internet.

2025-12-19 16:25:48 UTC

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Sheldon: Removing Joe Chill as the killer of Batman's parents effectively deprived him of his raison d'être.
Stuart: OK, you can throw all the French words you want, it doesn't make you right.
Sheldon: Au contraire.

2025-12-14 18:42:35 UTC

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There's been a couple of times in the last few weeks where we had a brief moment of sunshine inbetween long nights and cloudy days. You know that scene at the end of The Matrix where they break through the cloud layer and are the first humans to see/feel sunlight for hundreds of years? Not that, but it makes me appreciate it.

2025-12-14 00:29:39 UTC

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If it's any consolation it's pretty dark when I leave for work at 8am, and pretty dark when I come home at 4pm, this time of year. The occasional light show does make up for it a little.
(Oh, and [@Theorem_Poem](https://mstdn.social/@Theorem_Poem ), I think I promised to remind you of our winters after you noted "it never gets dark" during a summer visit 😉 )

2025-12-13 23:17:13 UTC

Another from last night, love the foreground definition and Ursa Major, depth of field FTW ;)
https://files.mastodon.social/media_attachments/files/115/714/784/489/500/890/original/be776cf0d25d2499.jpg

2025-12-13 14:59:50 UTC

Last night's aurora, not quite colours to the naked eye, but still fairly bright and quick moving. Pillars were easily visible.
https://files.mastodon.social/media_attachments/files/115/712/824/850/268/037/original/7225b50559218c7c.mp4
https://files.mastodon.social/media_attachments/files/115/712/831/167/848/904/original/cbf646da3034a7ac.jpeg
https://files.mastodon.social/media_attachments/files/115/712/836/086/389/167/original/74315bd305b9a986.jpeg

2025-12-10 23:56:29 UTC

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I say "making". I mean "convincing them it's just easier". Or maybe even "deep understanding"
This is a fundamental thing I struggled with at that age, it'd be nice to describe well.

2025-12-10 23:49:51 UTC

Top ideas for making high school science students think in Radians rather than Degrees?
e.g. for angular velocities etc?