Reply To: network security
The Focus Fusion Society › Forums › Lawrenceville Plasma Physics Experiment (LPPX) › Space and Aerospace Design in a Focus Fusion World › Reply To: network security
Aeronautvansig wrote:
The main problem of getting in space (LEO, at least) is not reaching a certain altitude, it’s reaching a certain velocity (about 7 km/sec) and once you are above an altitude where wings provide lift, you have accelerate to orbital speed within a given time with a given minimal acceleration or else you will simply fall back to Earth.
Yes, space ship 2 reaches its max speed of mach 3.5 after a 70-second burn and coasts up to its 110km max altitude.
This is way short of orbital velocity (~mach 24), requiring (24/3.5)²=47 times as much energy.
Consuming 200kW, one VASIMR VF-200 engine will have 5N thrust, and weigh 300kg. if you’re not already at orbital velocity, this doesn’t get you there.
Yepper. That’s why so many of us are looking forward to a Space Elevator. For some missions, the SE could eliminate or greatly minimize the amount of thrust required by ‘launching’ from near the tether’s end.