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PropulsionHow do conventional rockets work? |
Any rocket can achieve a very high speed if it accelerates for a long time. A conventional rocket has a hard time doing this because a huge amount of fuel must be carried into space in order for this to happen. This may make the rocket too heavy to lift off. Conventional rockets are generally designed to meet the speeds necessary for them to go where they need to go, and not go much faster.
Generally, a conventional rocket has to be going about 17,000 mph for it to achieve orbit; otherwise known as LEO -- Low Earth Orbit. This is the minimum speed for a spacegoing rocket. The farther from the Earth, the faster it needs to go. We list some other velocities for comparison:
|
Flight Plan |
speed required |
| Earth to LEO (low Earth orbit) | 17,000 mph |
| Earth to Earth escape | 24,200 mph |
| Earth to lunar orbit | 25,700 mph |
| Earth to GEO (geosynchronous Earth orbit) | 26,400 mph |
| Earth to solar escape | 36,500 mph |
With increasing speed it becomes harder and harder to gain another mile per hour. This is because the amount of fuel one has to carry becomes really big, and it becomes difficult and expensive to lift that much fuel into space. Solar escape velocity is nearing the practical limit of how fast one can move with conventional rockets.
What is the difference between an ion engine and a conventional one?
What is an orbit?
What are some kinds of orbits?
