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How do they make International space station to orbit the earth beyond earth's gravity acting on it? We all know that ISS is rotating at an altitude of just 350km away.How could ISS escape earth's gravitational pull?

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And what is the speed of ISS? I think that is the answer - the closer you are the faster is your speed (while angular velocity remains the same). –  Tomáš Zato Mar 1 at 18:50
The question might to be migrated to the Space Exploration site. –  Gerald Mar 1 at 21:03
Praveen - it is not rotating. It is orbiting - which means it is entirely within the action of Earth's gravity. It is not escaping - as you can see by the fact it keeps orbiting. –  Rory Alsop Mar 3 at 14:04

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Your question presumes that the ISS is beyond Earth's gravity, that it has escaped earth's gravitational pull. This is not correct. All objects with mass in the universe affect all other things with mass in the universe, the effect just gets weaker with distance. So the ISS is feeling the effect of gravity from Earth significantly more than the moon is.

The reason the ISS doesn't just fall to the earth, either directly or gradually spiralling towards the earth, is that it is travelling fast enough around the earth that it is continually "missing" earth. It is sometimes described as 'falling' constantly around earth.

If I am to be properly correct though, the reality is that ISS is in fact falling towards the earth, getting closer and closer to Earth all the time. It needs occasional boosts to push it further back out in it's orbit.

Just to blow your mind a little bit: The ISS is pulling on the Earth with the same force that the Earth is pulling on ISS.

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ISS is travelling with about 8 km/s around Earth. At that velocity the centrifugal force on the circular orbit is strong enough to cancel out gravity. The parts ISS is made of, needed to be accelerated to that speed by rockets.

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It doesn't really annihilate gravity, it just provides an opposite and equal force (almost) that keeps the satellite at a near constant altitude. –  polyphant Mar 3 at 15:33
@ChrisLovell Now used 'cancel out' instead; hope that's less misleading. –  Gerald Mar 3 at 20:30

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