I do not know what kind of efficiency you mean, but in terms of energy efficiency rockets are actually very good. A rocket engine transforms about 90% of the chemical energy of the propellants to kinetic energy. This is excellent.
The total energy efficiency of an orbital rocket can be defined as the potential energy of the empty rocket in orbit divided by the chemical energy in the propellants. Even here rockets are not that bad.
If you have a hydrogen powered rocket with a specific impulse of 4300m/s and a total delta-v of 9000m/s, your mass ratio is 8.109, so the propellant weighs 7.109 times as much as the empty rocket. But the empty rocket has a specific kinetic energy of about 30 MJ/kg, whereas the propellants only have a specific chemical energy of 11MJ/kg. The total efficiency is thus 30/(7.109*11)=0.38. Not too bad, eh?
The reason rockets are still so expensive is that most current rockets are direct descendants of ballistic missiles where cost was not important. And the shuttle is a f***ing joke.
The picture shows a really *tiny* space station with a progress and a soyuz docked. The station seems to be derived from the soyuz craft, but it will probably offer more room because it will not have a propulsion system. But it will still be really tiny. The habitable space will a cylinder about 2m in diameter and 4m in length. The crew will sleep in the soyuz, so this is not as bad as it sounds. I guess there is a huge window in the "base" of the space station.
The good thing is that this thing will probably be small enough to go up on a Soyuz launcher, so the price tag of 100M$ is quite realistic. If they can raise the money, they will build this.
I do not see what is so great about IE. I have a dual boot setup with linux/konqueror and windows/IE, and I do not see the slightest difference when browsing with konqueror. In fact I sometimes have to look at the window borders to see wether I'm in KDE or in windows.
I have to agree about mozilla though. Its very bloated, and even if they can make it work in the year 2002, they should be ashamed that less people can write a better browser (konqueror or opera) in less time.
regards,
tuttle
Best place to be when there is a war.
on
Data Mining?
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When there is a nuclear war and they get stuck in that thing, they can eat all that stored food and play quake 3 for the rest of their live:-)
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I do not know what kind of efficiency you mean, but in terms of energy efficiency rockets are actually very good. A rocket engine transforms about 90% of the chemical energy of the propellants to kinetic energy. This is excellent.
The total energy efficiency of an orbital rocket can be defined as the potential energy of the empty rocket in orbit divided by the chemical energy in the propellants. Even here rockets are not that bad.
If you have a hydrogen powered rocket with a specific impulse of 4300m/s and a total delta-v of 9000m/s, your mass ratio is 8.109, so the propellant weighs 7.109 times as much as the empty rocket. But the empty rocket has a specific kinetic energy of about 30 MJ/kg, whereas the propellants only have a specific chemical energy of 11MJ/kg. The total efficiency is thus 30/(7.109*11)=0.38. Not too bad, eh?
The reason rockets are still so expensive is that most current rockets are direct descendants of ballistic missiles where cost was not important. And the shuttle is a f***ing joke.
regards,
tuttle
There is an article on space.com.
The picture shows a really *tiny* space station with a progress and a soyuz docked. The station seems to be derived from the soyuz craft, but it will probably offer more room because it will not have a propulsion system. But it will still be really tiny. The habitable space will a cylinder about 2m in diameter and 4m in length. The crew will sleep in the soyuz, so this is not as bad as it sounds. I guess there is a huge window in the "base" of the space station.
The good thing is that this thing will probably be small enough to go up on a Soyuz launcher, so the price tag of 100M$ is quite realistic. If they can raise the money, they will build this.
This is not done by NASA. It is a private effort by the mars society. The capsule will be launched by a russian ICBM.
Why do all people assume that space flight==NASA?
I do not see what is so great about IE. I have a dual boot setup with linux/konqueror and windows/IE, and I do not see the slightest difference when browsing with konqueror. In fact I sometimes have to look at the window borders to see wether I'm in KDE or in windows.
I have to agree about mozilla though. Its very bloated, and even if they can make it work in the year 2002, they should be ashamed that less people can write a better browser (konqueror or opera) in less time.
regards,
tuttle
When there is a nuclear war and they get stuck in that thing, they can eat all that stored food and play quake 3 for the rest of their live :-)