[ResNet]

The fact that the telescope's cryocooler is acoustically symmetrical such that any vibrations made by each cylinder, and the actual flow of gas, is near-perfectly cancelled out is nothing short of amazing. [0]

Real Engineering made a video that covered this and more, which is well worth a watch. [1]

[0] https://webb.nasa.gov/content/about/innovations/cryocooler.h...

[1] https://www.youtube.com/watch?v=aICaAEXDJQQ (The Insane Engineering of James Webb Telescope)

[_fizz_buzz_]

This is the kind of thing I would never come up with and if I did I would never think it would be possible to implement. There are some seriously ingenious people out there.

[sslayer]

Teams, seriously ingenious teams.

[Cthulhu_]

There are, but they are rarely in an environment where they can use their ingenuity to their full extent; there's often budget and time constraints.

I mean I'm not saying there weren't any with these things, but they had a lot more leeway than in your average 9-5.

[tempodox]

It seems straightforward that cancelling internal vibrations as far as possible is a factor in the cooling, because warmth is movement (Brownian motion), and vice versa.

[mywacaday]

This video https://youtu.be/5MxH1sfJLBQ was posted here https://news.ycombinator.com/item?id=30729109 about how the actuators work on the James Webb telescope. It's a great watch.

[dav_Oz]

Robert Warden (original author of the paper "Cryogenic nano-actuator" (2006)[0]) did the first prototyping with Lego Technic [1]. From Lego to the JWST, I mean damn, like childhood dreams come true (:

[0]https://www.esmats.eu/amspapers/pastpapers/pdfs/2006/warden....

[1]https://m.youtube.com/watch?v=3WBrqUa_1yk

[dredmorbius]

Ball Aerospace, the manufacturer of the actual JWST actuators, traces its history to the Ball Corporation, of Ball Jar fame, which had relocated its manufacturing operations from Buffalo, NY, to Muncie, IN, following cheap fuel.

https://en.wikipedia.org/wiki/Ball_Corporation

That move was made on account of the Indian Gas Boom, which ran from the 1880s through the early 20th century, when it was discovered that there were large reserves of readily-accessible natural gas to be found in Indiana in field generally centered around Muncie.

As with other natural resource extraction booms before and since, proponents argued that the resources were inexhaustible, that prospectors had freedom to use or waste the resource in any way they saw fit --- large natural torches called flambeaux were a frequent sight. Over 90% of the gas was ultimately wasted, vented to the atmosphere.

The boom died out in the first decade of the 20th century.

https://en.wikipedia.org/wiki/Indiana_gas_boom

[nomel]

How is the position/correctness sensed? Do they calibrate based on the image of a known star (or something)?

[hi41]

Thank you for posting this. It looks like Robert Warden who wrote the paper really liked the video.

[neb_b]

SmarterEveryDay also has a really interesting episode about the sun shield

https://www.youtube.com/watch?v=Pu97IiO_yDI

[JohnBooty]

On a much less impressive (though more acccessible, at least for those of us who don't get to tool around with space telescopes on a regular basis) a similar technique is actually pretty common in consumer audio applications.

A number of Apple devices employ this technique, like the new iMacs. I know the 2019 (and presumably, the 2021) 16" MBPs do: https://thenextweb.com/news/the-new-imacs-have-force-canceli...

It's popular in higher-end subwoofers. While not the cheapest solution, a whole host of design issues is solved by simply adding a second amplifier and a second driver firing in the other direction. https://us.kef.com/kf92-subwoofer.html

If I'm not mistaken a fair number of portable Bluetooth speakers use something similar. If you're hearing a surprising amount of rattle-free bass come from a device that seems too small to pull it off, there's a decent chance they're using dual opposed drivers.

[grishka]

Do they use this in the 2021 MacBooks too? The thing sounds almost like it should not be physically possible to pack this much bass into such a thin device.

p.s. I'm so tired of random websites blocking Russian IPs because reasons

[sacrosancty]

I have a feeling that a huge amount of common engineering ideas that we all see as common sense, like gears, linkages, pistons, even the wheel, would have been beyond the imagination of most people before they were invented. I'd say we only know them because we've seen them. This other stuff might be common knowledge among specialists in that field, or not.

[akira2501]

That's where I really love James Burke's "Connections" TV series, it somewhat dispels this idea by showing just how interconnected discoveries and inventions were even in a far earlier age. One invention makes a new way of making money possible, this new way of making money comes with entirely new challenges and the capital to solve them. Unsurprisingly people naturally align themselves to solve these problems and capture some of that capital.

The idea of the "lone inventor" is a lovely one.. but I submit that they have not been the majority of force behind much of the invention our world now enjoys. Humanity itself is an iterative process.

[XorNot]

The Road Not Taken[1] short story tends to stick in my mind because of that. There's a lot of ideas that are extremely obvious once you see them, but without the prompt you might never get there.

[1] https://eyeofmidas.com/scifi/Turtledove_RoadNotTaken.pdf

[ramraj07]

That’s the beauty of technology though. Once someone figures out something, no matter how inexplicable, the mere suggestion of the possibility is enough to propagate a new normal where everyone assumes it’s pedestrianness.

The atom bomb, nuclear power, iPhones , the list is endless indeed.

[Diederich]

Yup, pretty much everything on this guy's channel is top drawer.

[dralley]

He's pretty good but perhaps not very critical. I'm not sure that's necessary for the types of videos he produces but the ones about the Boeing 787 and especially Nikola seem a bit flowery given everything else we know about them.

[bXVsbGVy]

The Launch Pad Astronomy is another great source for astronomic content [1]. I found pretty awesome the live show about JWST done with NASA scientists [2].

[1] https://www.youtube.com/c/ChristianReady [2] https://www.youtube.com/watch?v=Xv7QiNjx_MY

[throwthere]

Kind of like a flat four or six engine versus inline/V6.

[red369]

Flat fours and sixes definitely have a balance advantage over V6 engines, but I’m not sure there is much difference to a straight (in-line) four or six. They are also perfectly balanced until some higher order harmonic (something I can’t really remember at the moment). The advantage of flat engines are that they are much shorter, but then they’re heavier and more complicated because they have to have two heads. (Edited a typo in first sentence)

[AceJohnny2]

Motorcycles have a similar constraint, so I'm a little blasé on the technique.