A bit pedantic here.. I think you might be thinking about space tether propulsion. I don't know if that has been deployed yet. Magnetorquers, as in a device that uses magnets to rotate the satellite are very common in cubesats, you can buy it off the shelf

Hmm, there's a throwback.

I first encountered space tethers in 1980 reading an Introduction to Engineering text where the example was given of unrolling a flat spool of thin metal through shaping rollers to extrude a very long boom with a spring on the end to stabilise the orientation of a satellite.

That was one of the first times I noodled about with the dynamics of a pendulum in a potential field.

These days, of course, there's a few more tricks that can be done with a dangling lasso, including interacting with the magnetic field via a looped current.

That aside, I was curious about traditional magnetorquers and their variations actively providing force in the magnetosphere.

The Earths magnetic field has a lot of diurnal pulsing .. the gravitational field is lumpy but stable.

There's a control challenge in getting a smooth desired response from a choppy field.

Cheer's for the lookout though, it hadn't occurred to me that some would be talking about magnetic force against the field using "space tether" as the base description - my background was more about the field equations than the physical implementation.

( Magnetorquers are also used in the US Navy for twisting controls inside a fully sealed container. )

> several Chinese rocket companies

As much as I want to fly with Chinese rocket to encourage launcher competition and redundancy, export controls prevent me from doing that.

That's for you, but that won't stop the rest of the world

Microchip PolarFire boards (and PIC64 chips, which is basically just the CPU part of PolarFire without the FPGA fabric) can do that with asymmetric multiprocessing: https://www.microchip.com/en-us/products/fpgas-and-plds/syst...

Partly because reality is getting more stranger faster than satire. There's even an entire subreddit dedicated to that

Yeah, I don't think "surely no one seriously believes this" is viable now, if it was before. Of course, what you choose to do with that conclusion is still up to you.

I'm pretty sure the widespread adoption of Crocs heralded this tipping point. [viz., 'Idiocracy']

That sounds like Oberth effect in rocketry, where the faster you go the more efficient your rocket be: https://en.wikipedia.org/wiki/Oberth_effect

As someone that have successfully flown a RPi CM4 based payload on a cubesat, I fully agree with this. There's not enough funding in my research group to hire a dedicated test engineer so I need to both design and test my payload. It was a long lonely road

It does work at the end, but shortly after we got our first data from space, I decided to quit the space industry and become a test engineer at a terrestrial embedded company instead

I like my scintillator crystals.. they're purpose built to be very fluorescent

This is embedded C where standard abuse is a thing: https://thephd.dev/conformance-should-mean-something-fputc-a...

Factorio is the only game that I know that have Linux (and Mac) exclusive feature, which is non-blocking saving: https://www.factorio.com/blog/post/fff-408

Its not your normal soda-lime glass, its more of a glass-ceramic material that have very low coefficient of thermal expansion, something like zerodur: https://en.m.wikipedia.org/wiki/Zerodur , which means it can keep its shape and focus even under varying temperature

Interesting demo by Huygens Optics: https://youtu.be/qi8jmEbWsxU?si=rj0I3k-l74Xhg7vC

I think while the smaller mirror here is Zerodur, the larger one is just borosilicate,

https://astro.arizona.edu/news/rubin-observatory-achieves-an...

That would be an odd choice.

A large glass mirror once cracked because they "only" allowed one year for it to cool.

The second one was allotted three years.