Dаn̈ıel Раršlow 🥧 @pieist@social.cleverlibre.org

@simonbp @nyrath Again, thanks for this. I f-ing love NASA; one of human civilisation's most unalloyed goodnesses. I'll read up on this more closely as I have time.

@JohnShirley2023 (For a while I even had a credit card that with every purchase kicked them a few pfennigs, and had their emblem on it. I even gave a snooty waiter pause with it once. Pity they ended the relationship.)

@JohnShirley2023 Ha, literally a card carrying member. ✊

@JohnShirley2023 I feel like I commissioned and received a micronovel from a top author, for zero dollars and no cents. Seems wrong, somehow. What's your favorite charity? I'll kick them a few bucks.

@JohnShirley2023 OTOH Linda Blair's head rotating 360 degrees while she vomited pea soup gave us all a framework for recalling and describing our ex-girlfriends.

@sundogplanets The ability to teleport yourself to and from an orbital habitat at will is long overdue, don't you think?

@simonbp @nyrath Awesome. Thanks for that. The biggest part of my complaint-slash-incredulity is to do with the transfer couplings that have to retain atmosphere, resist torsional strain, be low friction and reliable. Not a job I would even want as an engineer. ("How about giving me a non-stupid problem to solve, please.")

No habitat involved in what you're talking about so it's mostly a "how much power and data complexity can we put into a coaxial link" problem.

Having read a lot of #Wolverine-centric #Marvel #Comics, I have to say I think "The Bubs" would be a good band name

@NotMyBub Just tell me "Bub" is a Wolverine reference

@ct_bergstrom My wife said "bring me some too"

#21C #WFH

By contrast, 2001's Discovery centrifugal habitat ring, thanks to being wholly contained within the pressure hull, was not different in any important way from having a hamster wheel in an Apollo command module. You could plan it in such a way that you could avoid the need for much in the way of crazy-robust and complicated couplings. A single -- admittedly probably pretty elaborate -- coaxial power and data link, some WiFi (1968 version) and simple package transfer of solids and liquids and you're all set. In principle.

#SF #Engineering #Spacecraft

@chris (Oh, 2001 depicts docking at the hub, because the space station in Act II is wholly rotating. Also, the Discovery's rotating section is wholly enclosed within the pressure hull, unlike say the one in The Martian or 2010, so they didn't have the massively problematic environmental coupling problem.)

@chris Eek. Yes. What killed me about the 2009 Star Trek film was seeing the Enterprise being built on the surface of the Earth. That'd be absurd, it's meant to spend its life in space, why build it down here and only to hoick it up there? Somehow I don't think the original ST developers would have made that mistake. (Though having everybody's feet pointing in the same direction still seems like a pointless requirement, even if you have artificial gravity.

(2001: A Space Odyssey got one thing right, at least: the rotating section was fully contained within the pressurised hull, so you didn't need to build and worry about atmospheric and life-support couplings. 2010 and The Martian, etc, didn't even have this mitigation.)

@chris Doesn't seem like the same scale of problem. The energy cost of spinning the ship is vanishingly small compared to that of sending it many light minutes outward into the Solar System, and if your fuel tanks or whatever don't want pseudogravity, put them at the axis. That's ideal anyway because it helps with the balancing issue as they are depleted.

@nyrath Yep. The worst part is the atmospheric seals. One or multiple rotating rings that have to keep air in? Nutjobbery.

(2001: A Space Odyssey, unlike say The Martian or 2010, didn't have that problem: the rotating ring was fully enclosed within the pressure hull, which at least avoids that huge problem. Putting the toilets in the nonrotating portion solves the sewage issue as well, though they don't depict that.)

(If you're using solar collectors and your path isn't radial to the sun, then you don't want the solar collectors to be mounted to the rotating part either. But we've already established that you'll want some minimal nonrotating section with power and comm links, so that's covered.)

My current #SF movie bugbear: Non-rotating #spacecraft with a large rotating section for the human habitat. Bonus points if the habitable part spans both the rotating and non-rotating portions and the crew can move freely between them.

It's an absurdly complex #engineering challenge to build it this way, it introduces an open set of failure modes that would not otherwise exist and there's no good reason for any of it that I can think of.

Instead, rotate the whole ship, and if there are a few things which for some reason must not be rotated (scopes, antennae and cameras, perhaps?) place them in the smallest and simplest possible unpressurised nonrotating segment at the axis.

@ct_bergstrom I have fresh hummus in the fridge and plenty of crackers so guess what you made me do