Originally Posted By: Paul
did you question why the ISS boosted?
was it because the ISS never did accelerate towards the earth and never did lose some of its orbital altitude?

The ISS was boosted because its orbital velocity had been reduced and the orbit had become lower than they wanted/needed.

The reason its orbital velocity was reduced was due to air resistance. We talk about the top of the atmosphere as if it were a fixed place. Below that point is atmosphere, above it is none. In fact it just slowly fades off until there is a height that we can say the presssure is too small to measure. It is still there and it does produce a small drag on the ISS and other satellites in LEO (low Earth orbit). So they occasionally have to boost it to get it back to the correct altitude.

Bill Gill

C is not the speed of light in a vacuum.
C is the universal speed limit.