|MadSci Network: Engineering|
Eliza, You're correct that it currently costs about $10,000 per pound to launch items on the space shuttle. It's a little less to launch on an unmanned rocket, but not much. There are several reasons for this. First, there are thousands of people required to build a rocket, prepare a rocket for launch, train personnel, and in the case of a reusable rocket like the space shuttle... maintain to rocket. These people are highly trained and are paid well for their knowledge. Second, it can cost billions of dollars to develop a new rocket and easily take 5-10 years. During this time, the company building the rocket is not receiving revenue on their investment. Third, all current launch vehicles have parts that are not reusable. Most unmanned rockets are one time use only. Even the space shuttle lets it's large fuel tank burn up in the atmosphere and must be replaced for each new mission. Also, rockets require lots of fuel. Fuel makes up over 90% of the weight of most rockets. On the space shuttle, the booster rockets and main fuel tank are almost entirely filled with fuel. It takes a lot of energy to accelerate a payload to a speed of 17000 miles per hour and to an altitude of 170 miles. Also the payload itself is often very expensive. Many new communications satellites cost almost a billion dollars. In the event of a launch failure or malfunctioning satellite, a company could go bankrupt. This usually means that the satellite needs to be insured, but that is a huge risk for the insurance company too (Lloyd's of London is about the only company willing to take the risk). Therefore, the insurance cost is enormous for a rocket launch. Several new rocket designs are showing promise for bringing down the cost to launch a payload into orbit. Many are being designed by small, private companies. These each offer innovative approaches that may help reduce launch costs. The current goal is to get costs down to about $1000 per pound of payload. Kistler Aerospace (http://www.kistleraerospace.com) is developing a reusable design using airbags for landing. Rotary Rocket Company (formerly http://www.rotaryrocket.com) is developing a reusable rocket that lands using helicopter-like blades for landing. Images available at http://www.lunar.org/docs/LUNARclips/v6/v6n2/Roton.html Also, the X-Prize Foundation (http://xprize.com) is offering a reward for groups to encourage development of manned rockets. Eventually the cost will come down enough that people may be able to buy tickets for a trip into space, but for the near future most of will just have to look up at night and dream. Todd Engelman
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