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Couldn’t we put it in a super long orbit that means it will revisit earth in a million years or something? Might be a nice surprise for whoever is around at tha

Couldn’t we put it in a super long orbit that means it will revisit earth in a million years or something? Might be a nice surprise for whoever is around at that point.

adolph 2y ago
Like Snoopy! https://skyandtelescope.org/astronomy-news/astronomers-might-have-found-apollo-10-snoopy-module/ https://skyandtelescope.org/astronomy-news/astronomers-might...
nickff 2y ago
It's considered unwise to leave uncontrolled vehicles in orbit, as they may hit other uncontrolled vehicles (or natural objects) and create debris.
- idiotsecant 2y ago
  An orbit like parent post is talking about is barely an orbit and more like an escape trajectory that just barely fails to escape.
  - nirav72 2y ago
    Would need lot of extra fuel to raise altitude for an escape trajectory. Fuel either brought up the gravity well at launch or later refueled in orbit. Of course not all satellites are designed to allow in-orbit refueling. Maybe an reusable orbital tug might be something that someone will come up with.
    - elif 2y ago
      It doesn't have to be one vehicle. You can launch 10 falcon 9s (perhaps even using the same booster) and have them take turns pushing.
      - grawp 2y ago
        Do you realize that 10 F9 flights means 10 new second stages and on those second stage someting has to sit and that something whatever that is - is completely dwarfed by ISS and it would have to be a new dedicated vehicle consiting of mostly fuel just to deorbit the sucker in one go. Original plain AFAIR was to use several Progress vehicles. And going to graveyard orbit with something like ISS is not just a few whole times more difficult but at least an order of magnitude more.
      - mr_toad 2y ago
        The ISS weighs 450 tonnes. Ten Falcon 9s (with 8 tonnes to GEO each, expended) couldn’t move it into a parking orbit. There literally isn’t enough current lifting capacity on Earth to do this.
        idiotsecant 2y ago
        You're trying to calculate this with weird units. ISS escape velocity orbit would require about 3200m/s delta-v. Yes, with chemical rockets this is like 800 tons of fuel. But you don't really need the high thrust of big chemical rockets. You could do it with ion engines which have a specific impulse between 10x to 100x higher than chemical rockets, bringing the total cost way down. It would take much longer, but it could be done.
- LeifCarrotson 2y ago
  Yeah, but this is the ISS we're talking about. Obsolete commsat number 723, sure, no one's going to care about deorbiting it, but the ISS has historic and cultural significance. Raise it a bit to a parking orbit, everything else can keep track of where it is, and a thousand years from space archaeologists can explore it. Or pack it inside otherwise empty Starships a few segments at a time and fly it down intact to put in a museum.
  - lxgr 2y ago
    The ISS will burn up in the atmosphere within very few years unless periodically boosted up. Boosting it all the way up to a more long-term graveyard orbit (i.e. several hundred kilometers) would consume a lot of fuel compared to a planned deorbit.
    - ortusdux 2y ago
      At one point they planned on using ion thrusters to try and keep the ISS in a stable orbit. I wonder how many it would take to push it into a graveyard orbit? Most of the energy for ion thrusters comes from solar, which the ISS has plenty of.
      - perihelions 2y ago
        - "Most of the energy for ion thrusters comes from solar, which the ISS has plenty of." The ISS rather has very low power relative to its mass. About 1/50th the power/mass ratio of the Dawn probe, for instance. This approach would take multiple decades, with the ISS as it currently is. It's worth remarking there's never been a spacecraft to date that's attempted a solar-electric spiral out starting from low Earth orbit. (The Boeing 702 satellites can spiral from GTO to GEO at least—though those have, again, far higher power/mass ratios than the ISS).
    - leptons 2y ago
      A deorbit would create a huge amount of chemicals in the atmosphere that are very harmful to the ozone layer. It might be worth sending up a few more rockets to give a big enough push to send the ISS into the sun (along with said rockets). https://www.space.com/starlink-satellite-reentry-ozone-depletion-atmosphere https://www.space.com/starlink-satellite-reentry-ozone-deple... https://www.space.com/deorbiting-impact-on-earth-atmosphere-climate https://www.space.com/deorbiting-impact-on-earth-atmosphere-...
simonh 2y ago
It would take a massive amount of energy to eject such a huge structure from very low orbit out of Earth orbit completely.
idiotsecant 2y ago
Does it have the delta v and structural strength for a maneuver like that in its current configuration? I agree it would be cool to put it in deep freeze for a few thousand years.
- gs17 2y ago
  Structural strength shouldn't be an issue, but it doesn't have the delta-v. They would probably need to find a way to attach some ion engine tug to it.
mrtksn 2y ago
Can you imagine, people rebuilding the society after collapse and this thing resembling the images in some very old artefacts returns from the skies.
- itishappy 2y ago
  ... moving at like a billion miles an hour before vanishing back into the blackness before humanity can react.
  - sameerds 2y ago
    ... that might explain Oumuamua!
m463 2y ago
can you protect an orbit with the "One Small Step to Protect Human Heritage in Space Act"?
bkberry352 2y ago
Answered in their FAQ[1]: > Decommissioning by boosting an object to a higher “graveyard” orbit to extend orbital lifetime is often done with smaller satellites operating near geostationary orbits (~36,000 km in altitude). This is not a realistic target for space station decommissioning because of the large mass of the space station and distance from its operational altitude to a “graveyard” orbit. Existing propulsive assets (spacecraft) do not have the capability to raise the space station’s altitude to such a high target. [1] https://www.nasa.gov/faqs-the-international-space-station-transition-plan/ https://www.nasa.gov/faqs-the-international-space-station-tr...
- wongarsu 2y ago
  For perspective, the ISS is currently orbiting at 400km altitude. Typical graveyard orbits are just beyond geostationary, so lets call it 36500km. Orbits get somewhat emptier beyond 2500km altitude, but you'd still risk spent rocket stages or defunct satellites hitting the ISS if you don't go all the way out beyond geostationary. Maybe you can stay at lower orbits if you dock a vehicle that can provide thrust for obstacle avoidance even after the main station powers off.
deleted 2y ago
[deleted]
perihelions 2y ago
It's far more expensive, in the orbital mechanics sense, to do anything like that than to "simply"* nudge an end-of-life satellite just enough to push into the atmosphere, when it's starting from an already-low orbit. *(The engineering here is not very simple)

Couldn’t we put it in a super long orbit that means it will revisit earth in a million years or something? Might be a nice surprise for whoever is around at that point.

adolph 2y ago

Like Snoopy! https://skyandtelescope.org/astronomy-news/astronomers-might-have-found-apollo-10-snoopy-module/ https://skyandtelescope.org/astronomy-news/astronomers-might...

nickff 2y ago

It's considered unwise to leave uncontrolled vehicles in orbit, as they may hit other uncontrolled vehicles (or natural objects) and create debris.

idiotsecant 2y ago
An orbit like parent post is talking about is barely an orbit and more like an escape trajectory that just barely fails to escape.
- nirav72 2y ago
  Would need lot of extra fuel to raise altitude for an escape trajectory. Fuel either brought up the gravity well at launch or later refueled in orbit. Of course not all satellites are designed to allow in-orbit refueling. Maybe an reusable orbital tug might be something that someone will come up with.
  - elif 2y ago
    It doesn't have to be one vehicle. You can launch 10 falcon 9s (perhaps even using the same booster) and have them take turns pushing.
    - grawp 2y ago
      Do you realize that 10 F9 flights means 10 new second stages and on those second stage someting has to sit and that something whatever that is - is completely dwarfed by ISS and it would have to be a new dedicated vehicle consiting of mostly fuel just to deorbit the sucker in one go. Original plain AFAIR was to use several Progress vehicles. And going to graveyard orbit with something like ISS is not just a few whole times more difficult but at least an order of magnitude more.
    - mr_toad 2y ago
      The ISS weighs 450 tonnes. Ten Falcon 9s (with 8 tonnes to GEO each, expended) couldn’t move it into a parking orbit. There literally isn’t enough current lifting capacity on Earth to do this.
      - idiotsecant 2y ago
        You're trying to calculate this with weird units. ISS escape velocity orbit would require about 3200m/s delta-v. Yes, with chemical rockets this is like 800 tons of fuel. But you don't really need the high thrust of big chemical rockets. You could do it with ion engines which have a specific impulse between 10x to 100x higher than chemical rockets, bringing the total cost way down. It would take much longer, but it could be done.
LeifCarrotson 2y ago
Yeah, but this is the ISS we're talking about. Obsolete commsat number 723, sure, no one's going to care about deorbiting it, but the ISS has historic and cultural significance. Raise it a bit to a parking orbit, everything else can keep track of where it is, and a thousand years from space archaeologists can explore it. Or pack it inside otherwise empty Starships a few segments at a time and fly it down intact to put in a museum.
- lxgr 2y ago
  The ISS will burn up in the atmosphere within very few years unless periodically boosted up. Boosting it all the way up to a more long-term graveyard orbit (i.e. several hundred kilometers) would consume a lot of fuel compared to a planned deorbit.
  - ortusdux 2y ago
    At one point they planned on using ion thrusters to try and keep the ISS in a stable orbit. I wonder how many it would take to push it into a graveyard orbit? Most of the energy for ion thrusters comes from solar, which the ISS has plenty of.
    - perihelions 2y ago
      - "Most of the energy for ion thrusters comes from solar, which the ISS has plenty of." The ISS rather has very low power relative to its mass. About 1/50th the power/mass ratio of the Dawn probe, for instance. This approach would take multiple decades, with the ISS as it currently is. It's worth remarking there's never been a spacecraft to date that's attempted a solar-electric spiral out starting from low Earth orbit. (The Boeing 702 satellites can spiral from GTO to GEO at least—though those have, again, far higher power/mass ratios than the ISS).
  - leptons 2y ago
    A deorbit would create a huge amount of chemicals in the atmosphere that are very harmful to the ozone layer. It might be worth sending up a few more rockets to give a big enough push to send the ISS into the sun (along with said rockets). https://www.space.com/starlink-satellite-reentry-ozone-depletion-atmosphere https://www.space.com/starlink-satellite-reentry-ozone-deple... https://www.space.com/deorbiting-impact-on-earth-atmosphere-climate https://www.space.com/deorbiting-impact-on-earth-atmosphere-...

simonh 2y ago

It would take a massive amount of energy to eject such a huge structure from very low orbit out of Earth orbit completely.

idiotsecant 2y ago

Does it have the delta v and structural strength for a maneuver like that in its current configuration? I agree it would be cool to put it in deep freeze for a few thousand years.

gs17 2y ago
Structural strength shouldn't be an issue, but it doesn't have the delta-v. They would probably need to find a way to attach some ion engine tug to it.

mrtksn 2y ago

Can you imagine, people rebuilding the society after collapse and this thing resembling the images in some very old artefacts returns from the skies.

itishappy 2y ago
... moving at like a billion miles an hour before vanishing back into the blackness before humanity can react.
- sameerds 2y ago
  ... that might explain Oumuamua!

m463 2y ago

can you protect an orbit with the "One Small Step to Protect Human Heritage in Space Act"?

bkberry352 2y ago

Answered in their FAQ[1]: > Decommissioning by boosting an object to a higher “graveyard” orbit to extend orbital lifetime is often done with smaller satellites operating near geostationary orbits (~36,000 km in altitude). This is not a realistic target for space station decommissioning because of the large mass of the space station and distance from its operational altitude to a “graveyard” orbit. Existing propulsive assets (spacecraft) do not have the capability to raise the space station’s altitude to such a high target. [1] https://www.nasa.gov/faqs-the-international-space-station-transition-plan/ https://www.nasa.gov/faqs-the-international-space-station-tr...

wongarsu 2y ago
For perspective, the ISS is currently orbiting at 400km altitude. Typical graveyard orbits are just beyond geostationary, so lets call it 36500km. Orbits get somewhat emptier beyond 2500km altitude, but you'd still risk spent rocket stages or defunct satellites hitting the ISS if you don't go all the way out beyond geostationary. Maybe you can stay at lower orbits if you dock a vehicle that can provide thrust for obstacle avoidance even after the main station powers off.

deleted 2y ago

[deleted]

perihelions 2y ago

It's far more expensive, in the orbital mechanics sense, to do anything like that than to "simply"* nudge an end-of-life satellite just enough to push into the atmosphere, when it's starting from an already-low orbit. *(The engineering here is not very simple)