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Moving off the orbit is not as easy. You basically have to slow down in order to de-orbit, and that requires rockets. These end of life rockets adds to the weig

Moving off the orbit is not as easy. You basically have to slow down in order to de-orbit, and that requires rockets. These end of life rockets adds to the weight of each satellite which adds to the cost of launching them.

buran77 6y ago
The problem that wooden satellites would address is space junk falling to Earth and aluminum burning up on reentry, leaving particles in the atmosphere: > We are very concerned with the fact that all the satellites which re-enter the Earth's atmosphere burn and create tiny alumina particles which will float in the upper atmosphere for many years
- ratsforhorses2 6y ago
  What about little drones that pushed them out of orbit?
  - ratsforhorses 6y ago
    https://www.hindawi.com/journals/jchem/2019/4753910/ https://www.hindawi.com/journals/jchem/2019/4753910/
Rebelgecko 6y ago
There's some interesting work that's been done with using electromagnetic tethers to deorbit
- vagrantJin 6y ago
  This is interesting. Cant we automate this and have drones tether the debris? It could launch from the ISS by mechnical propulsion (throw that bad boy with a mechanical arm)
  - Rebelgecko 6y ago
    The ones I've seen are mostly intended to be installed on cubesats as a primary or backup method of deorbiting. However if it works well I suppose they could also be put onto little probes that latch onto problematic debris. Dunno if that's cost effective
skunkworker 6y ago
Or do the opposite and use a hall effect thruster in order to maintain your altitude and velocity. Which is what Starlink has designed their LEO satellites to do, in order to have a natural failsafe in the event of a failure [1]. Though speculatively I've read that making sure the optics burn up in deorbit is a major problem to adding inter satellite laser links. [1] https://spectrum.ieee.org/tech-talk/aerospace/satellites/spacex-claims-to-have-redesigned-its-starlink-satellites-to-eliminate-casualty-risks https://spectrum.ieee.org/tech-talk/aerospace/satellites/spa...
random5634 6y ago
"that requires rockets" I'm curious about these absolute claims. Can a heavy mass object moving more slowly entangle a faster object to reduce velocity. Can solar sails be used to reduce or change orbits? Magnetic fields? Physical characteristics and profile of sat vs orbit? Put in a decaying orbit that is only maintained by a thrusters? Very interesting to hear that the only way to slow something down is with rockets. Not atmo drag. No mag drag. No solar pressure etc.
- krisoft 6y ago
  You are right, the grand parent post was not absolutely correct. I also suspect that you already know the answers to your own questions. :) But in case someone don't: "Can solar sails be used to reduce or change orbits?" Yes! It's a bit overkill, but yes that is something one can do. "Magnetic fields?" There are very promising results in that direction too. A satellite can unfurl a long thin conductive tether. The magnetic field of the planet generates a current in the tether and a net drag on the sat.(To be 100% honest I don't understand this solution enough, but "Terminator Tether" is a term one can search for more info.) "Physical characteristics and profile of sat vs orbit?" Maybe! On low orbits you can count on the very thin atmosphere to provide you some drag. It's a common practice for example with cube sats to not put them too high, so even if something goes wrong with their electronics they will deorbit on their own in a few months or years. You can also increase this drag by turning your sat to "face the wind" with the largest available cross-section. This trick doesn't really work on higher orbits though, and that's where "space junk" is generally a problem. "Put in a decaying orbit that is only maintained by thrusters?" I'm not sure what you mean. Thrusters are rockets. But yes, that absolutely works. With the usual caveats. You have to budget enough fuel for the manoeuvre, and if your ageing sat craps out you might not be able to command it anymore.

buran77 6y ago

The problem that wooden satellites would address is space junk falling to Earth and aluminum burning up on reentry, leaving particles in the atmosphere: > We are very concerned with the fact that all the satellites which re-enter the Earth's atmosphere burn and create tiny alumina particles which will float in the upper atmosphere for many years

ratsforhorses2 6y ago
What about little drones that pushed them out of orbit?
- ratsforhorses 6y ago
  https://www.hindawi.com/journals/jchem/2019/4753910/ https://www.hindawi.com/journals/jchem/2019/4753910/

Rebelgecko 6y ago

There's some interesting work that's been done with using electromagnetic tethers to deorbit

vagrantJin 6y ago
This is interesting. Cant we automate this and have drones tether the debris? It could launch from the ISS by mechnical propulsion (throw that bad boy with a mechanical arm)
- Rebelgecko 6y ago
  The ones I've seen are mostly intended to be installed on cubesats as a primary or backup method of deorbiting. However if it works well I suppose they could also be put onto little probes that latch onto problematic debris. Dunno if that's cost effective

skunkworker 6y ago

Or do the opposite and use a hall effect thruster in order to maintain your altitude and velocity. Which is what Starlink has designed their LEO satellites to do, in order to have a natural failsafe in the event of a failure [1]. Though speculatively I've read that making sure the optics burn up in deorbit is a major problem to adding inter satellite laser links. [1] https://spectrum.ieee.org/tech-talk/aerospace/satellites/spacex-claims-to-have-redesigned-its-starlink-satellites-to-eliminate-casualty-risks https://spectrum.ieee.org/tech-talk/aerospace/satellites/spa...

random5634 6y ago

"that requires rockets" I'm curious about these absolute claims. Can a heavy mass object moving more slowly entangle a faster object to reduce velocity. Can solar sails be used to reduce or change orbits? Magnetic fields? Physical characteristics and profile of sat vs orbit? Put in a decaying orbit that is only maintained by a thrusters? Very interesting to hear that the only way to slow something down is with rockets. Not atmo drag. No mag drag. No solar pressure etc.

krisoft 6y ago
You are right, the grand parent post was not absolutely correct. I also suspect that you already know the answers to your own questions. :) But in case someone don't: "Can solar sails be used to reduce or change orbits?" Yes! It's a bit overkill, but yes that is something one can do. "Magnetic fields?" There are very promising results in that direction too. A satellite can unfurl a long thin conductive tether. The magnetic field of the planet generates a current in the tether and a net drag on the sat.(To be 100% honest I don't understand this solution enough, but "Terminator Tether" is a term one can search for more info.) "Physical characteristics and profile of sat vs orbit?" Maybe! On low orbits you can count on the very thin atmosphere to provide you some drag. It's a common practice for example with cube sats to not put them too high, so even if something goes wrong with their electronics they will deorbit on their own in a few months or years. You can also increase this drag by turning your sat to "face the wind" with the largest available cross-section. This trick doesn't really work on higher orbits though, and that's where "space junk" is generally a problem. "Put in a decaying orbit that is only maintained by thrusters?" I'm not sure what you mean. Thrusters are rockets. But yes, that absolutely works. With the usual caveats. You have to budget enough fuel for the manoeuvre, and if your ageing sat craps out you might not be able to command it anymore.