@mcnees Claiming this as a particularly good Ten Thousand Moment, given your job and all 🤣😎
https://xkcd.com/1053/

@mcnees I thought so 😎
Other people have tried it by filtering gutter run-off from house roofs.

@mcnees Original post from a couple of weeks ago. I'm going to use this in our "learning to use a microscope" classes for first year (~12yrs) cos the grains are easy to get focus on, and they need to scan around looking for a target. Plus, y'know, meteorites on the roof of the school! https://mastodon.social/@_thegeoff/110277441977302628

I *think* I found some micrometeorites. The hook shaped thing is pointing at them. Magnetic, spherical-ish, metallic sheen. About 100 micrometres across, just visible to the naked eye. Collected from the roof of the school.

@mcnees There's some debate as to contaminating sources (say, grinding/welding fragments etc), but there's peer reviewed work on confirming they're real. I brushed up about a square metre of rooftop dust from the school (highest flat roof for tens of miles), autoclaved it because bird crap, "gold panned" it in a petri dish, then pulled off fragments with a paper-wrapped magnet. Ten minutes under a microscope showed ~10 metallic spheres...can't guarantee they're all micrometeorites, but a chance.

@mcnees What as in micrometeorite hunting methods, or my opinion on magnets?

Note that the "don't find meteorites with a magnet" advice doesn't really apply to amateurs hunting micrometeorites in rooftop dust. There are so common, and so small, that you're not going to destroy any research-worthy magnetic fields. (Although if you can come up with an efficient non-magnet method for that, I'd like to hear it. I've had some success in a "gold panning" style to filter out all the lightweight stuff before using a magnet.)

@mcnees "YOU! PUNY HUMAN! Give me the coordinates to your home system or DIE!"
"Really? OK. It's 0-0-0."
"But that's OUR home system!"
"Ah...yeah...I think I see what's happened here..."

@mcnees Why can't it be both? *cough*klausfuchs*cough*

@AstroKatie Ideally, to find some little nugget I don't know and find fascinating, in the worthy but established "astro outreach" lecture. Either new results a la JWST or, to steal an example from you, the angular diameter turnaround.

@mcnees I played with this from a science fiction angle and worked out that much of the observable universe is within a human lifetime from the naive version of the maths. I also like to fall asleep imagining the pressure from the mattress isn't gravity, but a spaceship's drive. It's surprising how far you can travel on 8 hours sleep...

@mcnees I seem to remember somebody calculated that there was a small chance of a single person observing a flash from an eyeball-neutrino interaction during a supernova in the 1980s?

@mcnees And given that there's a grand total of about 30 grams of the stuff on/in the entire planet at any given time, mostly just a few atoms here and there with a 22 minute half life, that's a hell of a discovery for the era.

@mcnees Wait until she hears you can do the cello number near the end on an electric guitar. Hell, what a series, kids at school who aren't much older are really into it, and I'm totally there for that.

@mcnees @drskyskull https://youtu.be/4VR9LJqZX50

@mcnees @duetosymmetry I keep a pristine sheet of each graph paper we use in a folder. Sometimes we'll run out (it's a high school, and not brilliantly funded) and a teacher will desperately need "just 20 sheets of x". So I colour photocopy them from my stash.

@mcnees Vernier scales are basically witchcraft. Measuring things to hundredths of a mm by hand, eye and simple mechanical engineering is just weird.

Cool one via a suggestion from @ Glazgow on twitter...dandelions are highly hydrophobic, you can dunk them in water and they come out dry.