|MadSci Network: Physics|
The orbital catapult idea is an idea that's been bounced around science fiction stories for many decades. Other ground launched capabilities have been and have since continued to be explored. I mentioned the orbital catapult...this name fits a broad group of possabilities from the simple mechanical catapult for "small" loads to the more advanced electro-magnetic rail launcher. The Space Shuttle was designed as a re-usable multiple mission/multiple payload configurable spacecraft, meaning that the original intent was to build a re-usable spacecraft which could perform any orbital mission ever required. As a result the Shuttle needs external and internal fuel tanks for orbital insertion(maneuvering to the desired hight above the Earth) and if needed orbital maeuvers during mission payload deployment and for emergency use during the re-insertion and landing side of its mission. The space shuttle was also original conceived to save money in the long term over an unrecoverable craft (rocket). Today, the technology is just beginning to surface which may in the future lead to the development of unmanned/remote guided spacecraft. Such spacecraft may also be launced by a ground-based launcher. As it stands today, it is not economically feasible to build such a spacecraft. Also, it is more feasible from a design point of view to carry your fuel and independent maneuvering ability with you onboard the craft. However, in the future with an orbital colony or an orbital platform free of the burden of Earth's gravity, a "catapult" of some sort may be employed to launch freight into the Earth's orbit for pick-up via an intra-solar(within our own solar system) shuttle, or even catapulted to a new destination....in the future anything may be possible.
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