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### Why does the ISS rotate exactly once per orbit?

Looking at the HDEV experiment, one can see that the orientation of the ISS is always the same with respect to the Earth. This means that the ISS must rotate exactly once per orbit (like the Moon ...
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### Could the ISS stop rotating wrt the stars for a few days, then start again?

Suppose for some reason it was particularly advantageous to stop the ISS from rotating once per orbit, so that it maintained a constant attitude with respect to the stars (or the Sun) instead of with ...
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### Does the "Tennis Racket Theorem" apply to the ISS? Does it rotate around its intermediate (unstable) axis?

Wikipedia's Tennis racket theorem begins: The tennis racket theorem or intermediate axis theorem is a result in classical mechanics describing the movement of a rigid body with three distinct ...
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### Could Magnetorquers be used on the ISS?

The way that the ISS manages it's attitude now is to use a set of reaction wheels for primary control, and occasionally firing small thrusters to allow the wheels to despin themselves. This isn't ...
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### Could an articulated permanent magnet work as a low-power cubesat magnetotorquer? Problems?

Conventional magnetotorquers for cubesats are electromagnets that produce torque in the Earth's magnetic field, and nearly all of the power they use just heats the copper through $\text{I}^2 \text{R}$ ...
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### Rotating in orbit?

Reading this question (Is the cupola, on the inside of the ISS, cold or warm to the touch?) prompted me to wonder about an object in orbit's orientation as it orbits its host object. For example, ...
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### Does the ISS yaw in orbit? And if so, why?

A NASA ISS reference guide (PDF; 37 MB) explains the use of reaction wheels -- Control Moment Gyroscopes (CMGs) -- to control the station's attitude/orientation. My understanding is the station is ...
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### Is the ejection of matter one way to get pushed the other way the only propulsion method we have?

I do mean propulsion (not gravity assist or the like). All the "rocket" engines I've seen (chemical, nuclear, ion, etc) seem to eject material one way to get the craft pushed the other way. ...
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### How do we manage the residual magnetic moment of magnetorquer with a ferromagnetic core?

I'm currently working on a control algorithm, specifically in detumbling, for a 3U cubesat. I'm using magnetorquers for actuation and magnetometers to receive feedback. If I have no current passing ...
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### Has the ISS ever "flown upside down"? Has the cupola ever "looked up"?

For a spacecraft in low Earth orbit let's call the zenith direction (vector away from Earth) "up". For most of its life I think the ISS has orbited with it's "up side" pointed &...
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### How well could the ISS attitude control system detect periods of astronaut activity?

The question Why doesn't ISS start to spin if people walk inside? is a good one partly because it has attracted several good, informative answers. One of them is particularly intriguing because it ...
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