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I would guess that the most expensive part of such an endeavor wouldn't be the launch; it would be developing and building a spacecraft capable of capturing it

I would guess that the most expensive part of such an endeavor wouldn't be the launch; it would be developing and building a spacecraft capable of capturing it and bringing it back. Even the Space Shuttle wasn't necessarily a perfect fit for the job as-is. Hubble was serviced many times, but it was specifically designed for on-orbit capture and servicing by the Shuttle. Before they decommissioned the shuttle they actually had to install an extra piece of hardware to make it feasible to capture and de-orbit using future non-crewed spacecraft. And even then that's just to make sure it crashes in a safe place, not to bring it home intact. There was also a mission to service a satellite that wasn't designed for the purpose, and they had a really hard time capturing it and very nearly had to give up after days' worth of failed attempts. It finally took simultaneous EVA by three astronauts to coordinate a successful capture (one to grab it by hand, two to get it onto a specialized adapter rig built just for that satellite so that the Canadarm could hold it), which is quite a thing considering that the Shuttle's only designed to allow two people on EVA at a time. This craft is likely tumbling, which I presume would make it unacceptably dangerous for a crewed mission (and certainly rules out anyone just going out there and grabbing it with their hands), in addition to making successful capture that much more difficult.

RobotToaster 1y ago
Wouldn't it be possible to "simply" match it's tumble?
- stevage 1y ago
  That sounds absolutely terrifying for the astronaut. Imagine the whole universe spinning past you every second. Not to mention the forces.
- throw_a_grenade 1y ago
  No, when it tumbles, it does it around its centre of mass. You'd have to get a craft that has empty area inside. If you know Elite, it has space stations where you dock by going inside, while matching station's rotation. That's only in one axis (and note the hangar goes through the axis of rotation, i.e. centre of mass). To add rotation around another axis would make the task impossible.
  - Zardoz84 1y ago
    like that station that is in orbit around a pulsar star and destroys anything trying to take off from it ?
  - bunderbunder 1y ago
    It might be possible if you have very powerful thrusters, functionally unlimited RCS fuel, and G forces don't matter...
- paul80808 1y ago
  Only if it is only spinning along one axis. Very likely to be spinning on multiple axis. That said, with enough money and effort I'm sure we could figure something out, like shooting it strategically with small projectiles to slow the spin, etc.
  - LegionMammal978 1y ago
    Unless acted on by an external force, all rigid objects only rotate about a single axis, do they not? That axis just might not be aligned with any useful parts you'd want to grab on to.
    - Ancapistani 1y ago
      You might enjoy this, if you haven’t seen it: https://www.youtube.com/watch?v=1n-HMSCDYtM https://www.youtube.com/watch?v=1n-HMSCDYtM
  - WJW 1y ago
    Anything "spinning among multiple axes" is just spinning around a single compound axis? There's no reason for a spacecraft to limit itself to any earthbound reference frame when it comes to matching frame with an incoming body from outer space.
    - slavik81 1y ago
      In three dimensions, the rotation around one axis can affect the distribution of mass around other axes of rotation. That change in the moment of intertia causes acceleration, which can result in chaotic motion even without the addition of any outside forces.
      - LegionMammal978 1y ago
        What do you mean by "other axes of rotation"? As long as the object is rigid and not acted upon by external forces, its axis should never change, since both the direction and magnitude of angular momentum are conserved. Wikipedia talks of "chaotic rotation" of astronomical objects, but only over long timescales due to gravitational interactions and thermal effects. On short timescales, its axis shouldn't change much at all, unless you bump into it and apply an off-axis torque.
chiffre01 1y ago
Is this one of the missions where the shuttle returned a satellite from orbit? There were a few: https://rammb.cira.colostate.edu/dev/hillger/Shuttle-related.htm https://rammb.cira.colostate.edu/dev/hillger/Shuttle-related...

RobotToaster 1y ago

Wouldn't it be possible to "simply" match it's tumble?

stevage 1y ago
That sounds absolutely terrifying for the astronaut. Imagine the whole universe spinning past you every second. Not to mention the forces.
throw_a_grenade 1y ago
No, when it tumbles, it does it around its centre of mass. You'd have to get a craft that has empty area inside. If you know Elite, it has space stations where you dock by going inside, while matching station's rotation. That's only in one axis (and note the hangar goes through the axis of rotation, i.e. centre of mass). To add rotation around another axis would make the task impossible.
- Zardoz84 1y ago
  like that station that is in orbit around a pulsar star and destroys anything trying to take off from it ?
- bunderbunder 1y ago
  It might be possible if you have very powerful thrusters, functionally unlimited RCS fuel, and G forces don't matter...
paul80808 1y ago
Only if it is only spinning along one axis. Very likely to be spinning on multiple axis. That said, with enough money and effort I'm sure we could figure something out, like shooting it strategically with small projectiles to slow the spin, etc.
- LegionMammal978 1y ago
  Unless acted on by an external force, all rigid objects only rotate about a single axis, do they not? That axis just might not be aligned with any useful parts you'd want to grab on to.
  - Ancapistani 1y ago
    You might enjoy this, if you haven’t seen it: https://www.youtube.com/watch?v=1n-HMSCDYtM https://www.youtube.com/watch?v=1n-HMSCDYtM
- WJW 1y ago
  Anything "spinning among multiple axes" is just spinning around a single compound axis? There's no reason for a spacecraft to limit itself to any earthbound reference frame when it comes to matching frame with an incoming body from outer space.
  - slavik81 1y ago
    In three dimensions, the rotation around one axis can affect the distribution of mass around other axes of rotation. That change in the moment of intertia causes acceleration, which can result in chaotic motion even without the addition of any outside forces.
    - LegionMammal978 1y ago
      What do you mean by "other axes of rotation"? As long as the object is rigid and not acted upon by external forces, its axis should never change, since both the direction and magnitude of angular momentum are conserved. Wikipedia talks of "chaotic rotation" of astronomical objects, but only over long timescales due to gravitational interactions and thermal effects. On short timescales, its axis shouldn't change much at all, unless you bump into it and apply an off-axis torque.

chiffre01 1y ago

Is this one of the missions where the shuttle returned a satellite from orbit? There were a few: https://rammb.cira.colostate.edu/dev/hillger/Shuttle-related.htm https://rammb.cira.colostate.edu/dev/hillger/Shuttle-related...