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Space Launch, Russia
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• Suborbital launch
• Orbital launch
In addition, if orbit is required, then much higher energy is needed as some sideways speed is needed. The speed needed depends on the altitude, less speed is needed at high altitude; however allowing for the extra potential energy due to altitude, overall, far more energy is needed to orbit at high altitude than lower.
The speed needed to maintain an orbit, near to the Earth's surface corresponds to a sideways speed of about 7.8 km/s, an energy of about 60MJ/kg. This is several times the energy per kg of practical rocket propellant mixes.
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