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Genuine question, related but not by a lot. How likely is it that Starlink and whatever amazon is planning will end up polluting space with satellite garbage t

Genuine question, related but not by a lot. How likely is it that Starlink and whatever amazon is planning will end up polluting space with satellite garbage that will make future missions difficult/impossible due to high velocity collisions?

danpalmer 6y ago
My answer as an interested layman but not an expert: Yes this is a huge concern, which is why attention is being paid to how these satellites will de-orbit. Up to maybe 10 years ago satellites were just put up there and at best would move out of the way a bit when they reached end of life, but most would just stay. Plus lots of things were just discarded from mission, or lost accidentally, creating more junk. All of this made space junk a big and growing concern... However, now everyone is very aware, so satellites have de-orbiting built in (and I think this might be a legal requirement now), orbits may be chosen with ease of de-orbiting in mind, more care is taken to letting junk accumulate, several companies are working on clearup mechanisms, etc. All this may mean that the worst-case scenario doesn't ever actually play out, and it's not that big a deal in the long run. We'll have to wait and see, but there will be a lot of money behind making this as little of an issue as possible so that the space industry can really take off.
Gwypaas 6y ago
Not at all for Starlink. The orbits are low enough to decay within 5-10 years if they are left without station keeping. Remember, "space" does not start at the karman line, it is a continuous transition. Although, they have a license for satellites at ~1100 km altitude. Those would need active deorbiting. The Starlink satellites are also designed to completely burn up in the atmosphere. This is one of the reasons why the first generation does not have laser-links, that was supposedly the hardest part to design fulfilling that criteria. That's actually one of the advantages of their proposed lowering of the orbits, they need to think even less about end of life questions and redundancy. Edit: See here for the continuous sweeping happening at lower orbits. https://www.reddit.com/r/space/comments/ld4vlq/gabbard_diagram_animation_of_space_debris_since/ https://www.reddit.com/r/space/comments/ld4vlq/gabbard_diagr...
- blisterpeanuts 6y ago
  The Starlink sats are also specifically designed to be forcibly de-orbited at end-of-life, rather than remain as space junk for however long.[1] 1. starlink.com
  - deleted 6y ago
    [deleted]
- m463 6y ago
  They want to lower those satellites to ~550km which seems to me to be significantly less likely to leave space junk around.
cambalache 6y ago
OK, asking from total ignorance here, shouldnt the companies putting these things in orbit (and benefiting from it) be responsible for safely decommissioning the satellites after their useful life is over? Shouldnt they be liable if their "space garbage" fuck other people/nation equipment?
- nickik 6y ago
  They are. Every sat launched needs to have a plan for decommissioning. You need to have enough fuel at to de-orbit the sat at the end of life. The problem is what happens if your sat breaks and you can't de-orbit it. I'm not sure if a company could held liable or get fined unless they ignored the rules. I don't think currently you are held liable if its an accident. Thankfully once we have Starship, the cost of taking space garage should start to be reasonable.
- wmf 6y ago
  For most conventional satellites (and let's not forget second stages), the cost of deorbiting it if it fails is immense because it essentially requires launching a "tug" which didn't even exist until recently. Because it was so exepensive, people were allowed to ignore it. We'll probably eventually look back on this attitude the same way we view 1970s cars that didn't use known safety features. SpaceX is being forced to innovate in this area because everybody realized the YOLO attitude towards space junk doesn't scale to thousands of satellites.
zamadatix 6y ago
Despite the strong responses already it's only been a recent development that Starlink requested all orbital shells be the 5 year decay orbit or lower (and that change still not approved yet). Assuming they go forward with that plan though even the worst case scenario is a relatively temporary problem - they've shown the satellites can move and de-orbit on command and when they don't the newly proposed highest shell is about a 5 year natural decay. Also it's not so much the concern about hitting a satellite on your way up (easy to track and space is spacey) rather the concern that over many years any 2 satellites in the shell will collide creating a lot of debris that could collide with more satellites in the shell and so on. That's why there are requirements about being able to move your satellites actively as part of these proposals, to prevent such a scenario from happening or growing if it did.
- teruakohatu 6y ago
  > they've shown the satellites can move and de-orbit on command Are there cost weight savings if they can remove the fuel or equipment needed to force a deoribit? So if a sat dies on day one they can just shrug and say it will burn up in 5 years. Or can they induce drag without extra equipment?
  - zamadatix 6y ago
    Technically yes, as long as it will de-orbit in less than 25 years you don't need to. That being said not being able to de-orbit on command or maneuver out of a collision course is going to make getting tens of thousands of such satellites approved much less likely. Also they are used as part of the normal operation of the satellites anyways, ~60 are launched together in one big clump and then the ion thrusters get them into the individual target orbits and keep them there over time (until fuel runs out trying to keep the orbit on track or the satellite stops being operationally useful), so getting rid of it does make it lighter but not necessarily better suited.

danpalmer 6y ago

My answer as an interested layman but not an expert: Yes this is a huge concern, which is why attention is being paid to how these satellites will de-orbit. Up to maybe 10 years ago satellites were just put up there and at best would move out of the way a bit when they reached end of life, but most would just stay. Plus lots of things were just discarded from mission, or lost accidentally, creating more junk. All of this made space junk a big and growing concern... However, now everyone is very aware, so satellites have de-orbiting built in (and I think this might be a legal requirement now), orbits may be chosen with ease of de-orbiting in mind, more care is taken to letting junk accumulate, several companies are working on clearup mechanisms, etc. All this may mean that the worst-case scenario doesn't ever actually play out, and it's not that big a deal in the long run. We'll have to wait and see, but there will be a lot of money behind making this as little of an issue as possible so that the space industry can really take off.

Gwypaas 6y ago

Not at all for Starlink. The orbits are low enough to decay within 5-10 years if they are left without station keeping. Remember, "space" does not start at the karman line, it is a continuous transition. Although, they have a license for satellites at ~1100 km altitude. Those would need active deorbiting. The Starlink satellites are also designed to completely burn up in the atmosphere. This is one of the reasons why the first generation does not have laser-links, that was supposedly the hardest part to design fulfilling that criteria. That's actually one of the advantages of their proposed lowering of the orbits, they need to think even less about end of life questions and redundancy. Edit: See here for the continuous sweeping happening at lower orbits. https://www.reddit.com/r/space/comments/ld4vlq/gabbard_diagram_animation_of_space_debris_since/ https://www.reddit.com/r/space/comments/ld4vlq/gabbard_diagr...

blisterpeanuts 6y ago
The Starlink sats are also specifically designed to be forcibly de-orbited at end-of-life, rather than remain as space junk for however long.[1] 1. starlink.com
- deleted 6y ago
  [deleted]
m463 6y ago
They want to lower those satellites to ~550km which seems to me to be significantly less likely to leave space junk around.

cambalache 6y ago

OK, asking from total ignorance here, shouldnt the companies putting these things in orbit (and benefiting from it) be responsible for safely decommissioning the satellites after their useful life is over? Shouldnt they be liable if their "space garbage" fuck other people/nation equipment?

nickik 6y ago
They are. Every sat launched needs to have a plan for decommissioning. You need to have enough fuel at to de-orbit the sat at the end of life. The problem is what happens if your sat breaks and you can't de-orbit it. I'm not sure if a company could held liable or get fined unless they ignored the rules. I don't think currently you are held liable if its an accident. Thankfully once we have Starship, the cost of taking space garage should start to be reasonable.
wmf 6y ago
For most conventional satellites (and let's not forget second stages), the cost of deorbiting it if it fails is immense because it essentially requires launching a "tug" which didn't even exist until recently. Because it was so exepensive, people were allowed to ignore it. We'll probably eventually look back on this attitude the same way we view 1970s cars that didn't use known safety features. SpaceX is being forced to innovate in this area because everybody realized the YOLO attitude towards space junk doesn't scale to thousands of satellites.

zamadatix 6y ago

Despite the strong responses already it's only been a recent development that Starlink requested all orbital shells be the 5 year decay orbit or lower (and that change still not approved yet). Assuming they go forward with that plan though even the worst case scenario is a relatively temporary problem - they've shown the satellites can move and de-orbit on command and when they don't the newly proposed highest shell is about a 5 year natural decay. Also it's not so much the concern about hitting a satellite on your way up (easy to track and space is spacey) rather the concern that over many years any 2 satellites in the shell will collide creating a lot of debris that could collide with more satellites in the shell and so on. That's why there are requirements about being able to move your satellites actively as part of these proposals, to prevent such a scenario from happening or growing if it did.

teruakohatu 6y ago
> they've shown the satellites can move and de-orbit on command Are there cost weight savings if they can remove the fuel or equipment needed to force a deoribit? So if a sat dies on day one they can just shrug and say it will burn up in 5 years. Or can they induce drag without extra equipment?
- zamadatix 6y ago
  Technically yes, as long as it will de-orbit in less than 25 years you don't need to. That being said not being able to de-orbit on command or maneuver out of a collision course is going to make getting tens of thousands of such satellites approved much less likely. Also they are used as part of the normal operation of the satellites anyways, ~60 are launched together in one big clump and then the ion thrusters get them into the individual target orbits and keep them there over time (until fuel runs out trying to keep the orbit on track or the satellite stops being operationally useful), so getting rid of it does make it lighter but not necessarily better suited.