why do rockets take so long to get to the ISS?

277 viewsOtherPlanetary Science

The ISS is around 400km above us. A rocket needs a speed of at least 8km per second to get to space. If we cut out the acceleration part it could in theory reach the ISS in around 50 seconds. Even if we factor in the acceleration part etc. it should still be very quick up there. Yet the fastest possible time to get to the ISS is 4 hours. That would be an average speed of 100Km/h which is way slower than the speed of the rocket after a few seconds. Why the long journey?

In: Planetary Science

18 Answers

Anonymous 0 Comments

orbit means lateral speed, not just altitude. you could strap on your bionic legs and leap 400 km into the air. then wave at the space station as it goes whizzing by, but you would then fall back to roughly the same place you jumped from. in order to be in orbit, you have to be moving parallel to the earth surface, faster than you are falling.

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