Timeline for Isn't Starship way too big?
Current License: CC BY-SA 4.0
8 events
| when toggle format | what | by | license | comment | |
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| Apr 25, 2021 at 20:55 | comment | added | Christopher James Huff | That's completely wrong. The whole reason for the tether's existence is to apply an acceleration to the target. You can't deorbit the target without doing so. Applying the 260 m/s delta-v needed for deorbit from ~500 km with a 500 m radius of rotation means accelerations of nearly 14 gravities. Most satellites would simply be torn to bits during the swing, no matter how gentle your grappling mechanism is. Momentum exchange tethers might be useful, but not for this. | |
| Apr 25, 2021 at 20:25 | comment | added | Loren Pechtel | @ChristopherJamesHuff The only thing that takes high acceleration is the grapple and cable. | |
| Apr 25, 2021 at 11:32 | comment | added | Christopher James Huff | No, it can't. You're unavoidably going to be applying high accelerations to the target, or you're not slinging it anywhere. Realistically, that's going to end with you applying high accelerations to part of the target, while other parts of the target fly in every direction. You need targets with a grapple fixture that were structurally designed specifically to operate with momentum exchange tethers and which are still active and functioning enough to handle their side of the required maneuver. That makes it fairly useless for debris disposal. | |
| Apr 25, 2021 at 4:11 | comment | added | Loren Pechtel | @ChristopherJamesHuff So long as the velocity difference is low (you go for something in a similar orbit) the grapple can absorb the velocity difference. | |
| Apr 25, 2021 at 3:24 | comment | added | Christopher James Huff | That kind of momentum exchange will be difficult enough with cooperative targets designed for it, and even that will require precisely matching your target's orbit to a degree you're unlikely to achieve moving on from a previous one. Try it with anything else and you're likely to tear your target to bits. | |
| Apr 25, 2021 at 1:04 | comment | added | Loren Pechtel | @ChristopherJamesHuff If you can lift a large enough craft for deorbiting you can do it without much propellant. Throw out a grapple, capture something. Give it a yank, the junk goes into a lower orbit, you climb--aiming for the next piece of junk. You only need to burn if there's no suitable target, or when you've climbed above the junk and need to go back down. | |
| Apr 24, 2021 at 21:44 | comment | added | Christopher James Huff | Another angle on the last part: it also means it's a lot cheaper to make tugs to haul defunct satellites into disposal orbits or deorbit them entirely (or to carry devices to capture and contain smaller bits of debris), and plenty of room to put them up alongside other payloads. Especially since tugs are mostly propellant, which is only expensive in orbit due to its launch costs. | |
| Apr 21, 2021 at 22:16 | history | answered | Loren Pechtel | CC BY-SA 4.0 |