One door closes, and another opens. · 8:57pm Apr 28th, 2021
Don't worry, this isn't about me personally.
Michael Collins, the member of Apollo 11 who didn't step on the moon, died last night.
While looking up details of the death, I ran across his Twitter page. Apparently, despite cancer and advanced age, he was a very active user, and enthusiastic about boosting space exploration literally up to his last day on Earth.
And while looking at his Twitter, I saw something which had totally missed my attention: a flight of a system that will test a method of de-orbiting future dead satellites, thus reducing space junk.
Now, this won't get rid of existing space junk (like Mike Collins's camera from Gemini 10), but this will serve as a test bed for future projects that could do just that. The flight consists of two satellites, a chase and a target, and they will attempt progressively more difficult intercepts and re-docking to explore just how difficult it is to find, match speeds with, and grab orbital debris. That data can be carried forward to other targets that don't have the standardized docking system, somewhere down the line.
This is low-key stuff, but it's fascinating as all hell.
And it's also an excuse to link to this:
His passing is so sad. But the space junk removal tests are a positive sign. Sigh. Pandemics make everything seem worse.
Idiots who explode stuff in space above the 'it will burn up in a week or two' line deserve a special place tied to the outside of the space station for a few months. O2 optional.
For large objects, the tether and object routine seems promising. Think of it as:
Space <- O---------o -> Earth
(that's a gravitationally stabilized widget with the little object hanging down closer to Earth)
The tether cuts through magnetic lines of force much like a generator does on Earth, and generates a current, which can be ignored or used to power a light bulb heater. The key is you don't get something for nothing, and the generation of the current causes drag, which will eventually (months/years) cause the tethered object to descend into the atmosphere, and from there, poof. (unless it's Skylab-large, in which case WHUMP)
When you get down to softball-sized and smaller, we're about to some sort of ion-thrustered baby tug who runs around and 'bags' them one at a time, and ideally grinding up the results into powder and using that for reaction mass. Think of it as the Star Trek Planet Killer, writ very small.
Tiny bits like sand may be best maneuvered in front of and 'caught' with a catcher's mit device.
Edit: The actual space-based use of tethers to produce electricity is far more complicated than just running a long copper wire and plugging in an iPhone, since current is a circuit. Using one to just break lines of magnetic force is far easier and heats it up to the point where melty-spots are a significant issue, so I'm leaving the actual design to the engineers.
5508782
Sounds like you’ve done some research on this
even if he didn't step on the moon he was still a hero.
5508804
I was a member of L5 and still am an incurable geek, as you know. :)
Men like him didnt grow in trees. They were made with titanium balls. Nothing but respect for the man.
5508886
I’m not sure either are the best way to create new people
5508881
Neeeeeerd!
A very interesting idea, hope they go with it! He shall be missed.
To the man who took the first 'everyone-elsie'; may you rest among the stars.
5508782
Current in a single wire?
(well, there'd be minutes/hours period AC, but it's hard to believe it would be relevant to anything)
5514104 It's the same thing as taking a magnet and running it rapidly along an aluminum plate. Eddy currents are magic.
5514114
That wire has neither place for Eddy currents to flow nor magnetic field changing at any significant rate --- everything at numerator is tiny. I remember reading about something vaguely similar somewhere, but those guys were trying to pick up free electrons from ionosphere (there's concentration gradient with height)
5514140 There have been a lot more space tether missions that I ever expected, including one that was supposed to go *up* instead of down. (mind boggled) Electrodynamic tethers were what I was thinking of in the link. I had only known about TSS-1R.