> The Chinese space agency just launched a man into Earth orbit. The > agency should be congratulated!
The taikonaut just returned Beijing safely. The entire process is very successful. > > This is good news, in that there may be more interesting crewed space > exploration over the next generation. After the landing on the moon, > the US and the Soviet Union stopped interesting crewed space > exploration. In the upcoming decade, I am sure China will be quite active in the space exploration. > > The bad news is that the Chinese space agency choose the same > expensive method for going into space as the US and the Soviet Union. > To some extent, this makes sense as it is cheapest method. It is a > follow up of the 1930s German experiments in `long range artillery > without the gun barrel', and is known to work. Moreover, launching a > human into space is difficult. > > Sadly, the cost of this method is always high. It is expensive to > throw away a precision instrument, the rocket, after one use; and the > energy densities of chemicals mean that rockets will carry small > payloads. > > >From a military point of view, cost does not matter, since the goal is > to build a device that can destroy an enemy city. One rocket is > cheaper than 1000 manned bombers, as were used for city raids in World > War II. (In World War II, the US used flights of 500 to 1000 manned > bombers to destroy 62 cities and two flights of one bomber each to > destroy two more cities, using nuclear weapons.) > > However, for rockets, from a human travel point of view, the price has > to come down. That means using air augmented rockets. With such > rockets, oxygen is taken from the air for the first part of the trip. > Because the rocket does not have to carry all its own oxidiser, the > effective specific impulse doubles. > > (Nuclear thermal rockets built and tested on the ground in the US > triple the effective specific impulse. However nuclear thermal > rockets release fission products into their exhaust, and when > launched, some will crash. So earth-to-orbit nuclear thermal rockets > are a bad idea. In space nuclear rockets are a good idea; but the big > issue is how to get from earth to orbit.) > > Unfortunately, air augmented rockets are more expensive and risky to > develop than traditional rockets. No one has developed them, although > the idea has been around since at least the 1950s. > > Also, I suspect that countries that have developed traditional long > range rockets want to keep them expensive. The governments think of > them mainly as a form of nuclear artillery, and don't want the > equivalent of second-hand bombers being purchased by less rich foreign > nations. If rocket flights were cheap, many rockets would be built. > Eventually, they would be sold. There is no difference between a > civilian freight and passenger carrying rocket and a military one. In > both situations, the purpose is to carry mass into orbit. The mass > could be civilian passengers or a re-entry vehicle with a warhead. > At the current stage, I think the cost is not a big concern for space exploration, that will only become a factor to consider when we try to commercialize the space resource. Safe is the first priority to consider for the project. > Anyhow, my hope is that the Chinese launch will lead to more interesting > exploration over the next generation. I am sure it will be. Maybe free software can be applied in the future by the Taikonaut. Rgds, H. -- -----------------------------------------* Hong Feng | Publisher, Free Software Magazine | Chairman, Chinese TeX User Group | [EMAIL PROTECTED], [EMAIL PROTECTED] | http://www.rons.net.cn/hongfeng.html | -----------------------------------------* _______________________________________________ http://www.mccmedia.com/mailman/listinfo/brin-l
