I mean "attitude" makes perfect sense to those of us who actually work in aerospace. It's related to all the terms you listed but none of them are strictly equivalent.
But go ahead and be snarky if it makes you feel better?
People might wonder why attitude control is important. First and foremost: power. Solar power requires that the solar arrays be directed toward the sun. Losing attitude control means that they'll lose efficiency and thus power. This isn't a big deal in the short run, but long term is a big deal. Surely they'll have this fixed before that comes into play.
Aside from that, there's a lot of other smaller factors such as being able to orient the station to boost orbit every so often. Even though they're in Low Earth Orbit, there is a just enough atmosphere to cause the orbit to decay slightly over time, and this has to be compensated for by boosting the orbit. No attitude control = no orienting thrusters.
Perhaps more important than keeping the solar arrays pointed at the sun is keeping the radiators out of direct sunlight. The problem in space isn't so much freezing as cooking because there is no atmosphere between you and the sun and the only way to vent heat is inefficiently as radiation.
If the radiators started cooking in direct sunlight the station would get uncomfortably hot in a hurry.
I believe the ISS also orients its solar panels edge-on to prograde (direction of orbit) at night to minimize drag, so that’s another consideration of attitude control failure. Still second order to the radiators, though.
>Even though they're in Low Earth Orbit, there is a just enough atmosphere to cause the orbit to decay slightly over time, and this has to be compensated for by boosting the orbit
Just to expand on this a little (since it's gaining new relevance with the lower LEO and VLEO large constellations getting planned/launched), orbital life times drop non-linearly with altitude, atmospheric drags plays a big role fast until hundreds of km above the Karman line. An oldie and simplified but goodie site here [0] gives a decent basic overview. Remember that this will also vary, the atmosphere is affected by temperature and other factors.
Particularly since the ISS is manned and mass was very restricted, its altitude is a tight balancing act between high enough to not need to boost too often for comfort/practicality and as low as possible to reduce radiation exposure and stay away from the inner Van Allen radiation belt, which can get quite low indeed on occasion based on solar activity and geographic areas. It does mean though that ISS reboosts have to happen fairly regularly.
One big area of current interest this has an impact on is orbital debris lifetimes. There's an excellent Gabbard diagram animation [1] on Reddit that's worth a look if you haven't seen it before. You can see the decay rate very visually. Having constellations be very low is valuable for passive fail-safety in case of loss of control or collisions.
`nslookup` shows that the IP addresses for ustream.tv and video.ibm.com are the same ones. I also recall looking at ISS live streams on ustream.tv a couple of years ago.
for people curious, when that website is not broken https://www.internationaldockingstandard.com/download/IDSS_I... , there is the list of the moment of inertia of the ISS around various axes and the force and torque limits a docking ship as to respect.
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[ 2.8 ms ] story [ 82.1 ms ] threadBut go ahead and be snarky if it makes you feel better?
Aside from that, there's a lot of other smaller factors such as being able to orient the station to boost orbit every so often. Even though they're in Low Earth Orbit, there is a just enough atmosphere to cause the orbit to decay slightly over time, and this has to be compensated for by boosting the orbit. No attitude control = no orienting thrusters.
Obligatory Scott Manley video that's way better than what I just said: https://www.youtube.com/watch?v=fDp8jbP_22c
If the radiators started cooking in direct sunlight the station would get uncomfortably hot in a hurry.
Just to expand on this a little (since it's gaining new relevance with the lower LEO and VLEO large constellations getting planned/launched), orbital life times drop non-linearly with altitude, atmospheric drags plays a big role fast until hundreds of km above the Karman line. An oldie and simplified but goodie site here [0] gives a decent basic overview. Remember that this will also vary, the atmosphere is affected by temperature and other factors.
Particularly since the ISS is manned and mass was very restricted, its altitude is a tight balancing act between high enough to not need to boost too often for comfort/practicality and as low as possible to reduce radiation exposure and stay away from the inner Van Allen radiation belt, which can get quite low indeed on occasion based on solar activity and geographic areas. It does mean though that ISS reboosts have to happen fairly regularly.
One big area of current interest this has an impact on is orbital debris lifetimes. There's an excellent Gabbard diagram animation [1] on Reddit that's worth a look if you haven't seen it before. You can see the decay rate very visually. Having constellations be very low is valuable for passive fail-safety in case of loss of control or collisions.
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0: https://www.spaceacademy.net.au/watch/debris/orblife.htm
1: https://old.reddit.com/r/space/comments/ld4vlq/gabbard_diagr...
Still lots of investigation to do and probably a permanent fix incoming, but no big risk of them falling out of the sky right now.
Live ISS stream: https://video.ibm.com/channel/live-iss-stream (Currently no video, intermittent audio.)
Never knew a livestream existed and now I'm clued to my headset.
It’s all about the orientation, #headduck
(I have been waiting decades to make that joke.)