Quote:
Originally Posted by kiwi lover  THe space shuttle never attains escape velocity - only the vehicles that've gone to outer space need that - be in solar-system probes, or the Apollo missions to the moon. The shuttle attains orbital velocity which keeps it in orbit, which is about 17,500mph.. escape velocity I believe is about 25,000 mph which allows the craft to 'escape' Earth's orbit and go to the moon or planets or wherever.. |
Wellll technically, the apollo missions did not attain escape velocity because the moon is in orbit around the earth.
Look, it may seem counter intuitive, but in orbit, the more power you add, the slower you go relative to the surface of the earth. Let's say you're in orbit around the earth at the ISS. You want climb up to your satelite parked in geosynchronous orbit, you don't do what would be the intuitive thing to do, and turn so that your exhaust is perpendicular to the surface of the earth, then blast straight up. What you want to do is burn "prograde" so that you're in the same direction as your orbit. It is best to do this at the peregee (the closes approach of your orbit to earth). As you add power, you're increasing your energy, that elongates your orbit and puts the apogee (the highest point away from earth up where the geosynchronous satellite is if you timed it right). Then when you get up to "apogee," you have to burn so that your peregee is now equal to you're apogee and you're in a circular orbit. Now since you are higher, you will be moving slower relative to the surface of the earth.
-Pat