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13

The ISS microgravity is generally considered to be of pretty poor quality, but the major cause of that is vibration from mechanical equipment and astronaut movement rather than atmospheric drag and reboosts (which are infrequent). For many experiments it's adequate, for others it is not - alternatives include drop tower tests and drag-free satellites such ...


13

Ignoring the ISS, the question is simply whether light pressure on the sail can counteract the drag on the sail from atmosphere. Light pressure near Earth is about $10 \mu Pa$ (with optimum geometry and no eclipse). So the question is what is the drag force per square meter of sail. We know that the ISS experiences about 0.2N of drag, and its area is ...


12

No propellant was ever transferred from the Orbiter to the ISS. Shuttle reboosted ISS using the Reaction Control System (RCS) jets. The small 24 lbf vernier RCS jets were used. The steps for executing the reboost were called out in the Flight Plan. Here's an example from STS-130. Note that it was done at the very end of the docked phase (straddling the ...


11

Here is a rough estimate. The ISS's height drops at the rate around 10 meters per day. The energy of a body of mass $m$ in a circular orbit of radius $r$ is $E=-\frac{\mu m}{2r}$, so $$ Fv=\frac{dE}{dt}= \frac{\mu m}{2r^2}\frac{dr}{dt}. $$ Since $v=\sqrt{\frac{\mu}{r}}$, $$ F=\frac{m v}{2r}\frac{dr}{dt}. $$ Substituting $m=4\cdot 10^5$ kg, $v=7800$ m/s, $r=6....


10

this answer shows a period of time when the ISS lost only 10 meters of altitude per day, and this answer shows a period of time when it lost about 100 meters a day. Based on this kind of analysis that requires a delta-v of between 6 and 60 mm/sec. The ISS is about 400,000 kg. update: this answer shows more extreme periods with altitude losses of between 7 ...


8

One could determine the planned locations of the crew during any given time by referring to the Flight Plan. For the reboost event described in the earlier answer https://space.stackexchange.com/a/39552/6944, we can look at where they were: At the initiation of the reboost, the shuttle commander would have been in the Orbiter, presumably with another ...


8

I'm interpreting this question as "Did adjustments have to be made to the shuttle Digital Autopilot (DAP) while it was controlling the mated stack (shuttle + ISS) - i.e. was a maneuver tried, the results of the trial evaluated, and the DAP settings changed based on the results of the trial during the same shuttle mission?" If that interpretation is correct, ...


6

Bartolomeo is not Australian but European. It's a platform designed by Airbus DS. It will be installed outside the Columbus laboratory on the COL-EPF (Columbus Laboratory Module Exposed Payload Facility). This platform will be installed, serviced and operated in a collaborative public-private utilization scheme with ESA, NASA, and other partners in the ISS ...


5

If it's not "a solid or liquid propellant", and more fuel-efficient, and not magical, it's presumably some sort of electric thruster. This Interesting Engineering article (CW: journalism) says Tiangong uses ion thrusters: The space station’s core Tianhe module, which will welcome its first astronauts later this month if all goes to plan, is ...


4

At least when the reboosts were done using the shuttle, there was no procedural call out to secure anything. This answer steps through the procedures and includes links to the full text of both shuttle and ISS procedures. How was the Space Shuttle Orbiter used for ISS Reboost?


4

Theoretically, it could, but why use the larger, more expensive rocket engines when you could just use a less expensive, smaller draco engines? Super Dracos are off axis, meaning that any thrust from them will be less efficient than if they were directly in the desired direction. They burn real quick, which means more force that the station has to absorb, ...


4

This question is asking for an official answer, and that would take someone who is official to answer. I can at best hazard some guesses. One reason is that the Sun is approaching the end of what was a low activity solar cycle. We can look forward to several months, minimum, of very low solar activity. Several months of inactivity is the norm for the lull ...


3

They float from Node 2 (Harmony) into the Destiny module - so towards 'aft' of the station. That means the station is propelled from the rear - either by thrusters installed in the Zvezda module or by a Progress spacecraft docked to the rear-most port of Zvezda. (obviously the thrusters are directed 'away' from the station not to spray it with hydrazine, so ...


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