So... you might want to check your facts.
The Americans (Cassini spacecraft) dropped the European Probe (Huygens) on Titan.
The press release is somewhat U.S. centric but the first to orbit two separate Planetary bodies is probably a valid claim.
The Deep Space series of spacecraft are technology demonstrations. Some many carry science instruments but the primary focus is to test technologies for use in later missions.
RTG's last a long time but not 50 years. The half life of Plutonium and the degredation of the thermoelectric components will take their toll over time.
The current RTG program called MMRTG (Multi-Mission RTG's) delivers ~120W electric at the begining of life and after 14 years it drops to ~100W electric.
As for MER and the solar panels, the dust build-up is fairly limited.Power problems will probably kill the rovers but it will be the batteries and not the solar cells. Remember that the rovers have Lithium-ion batteries just like your laptop which have high energy density but loose their capacity over time.
Eventually the rover will not be able to store enough power to run the heaters that keep it warm at night and it will freeze.
Yes this is true. However a gas core nuclear reactor is far more likely to become reality than any sort of NTR. This is primarily due to the cost of development which would require a testing facility to ensure that all the exhaust does not escape into the enviroment.
There is nothing wrong with the idea of NTR and in my opinion they are a much better solution than electric propulsion (pick your type). It seemed that both the person who posted this and many slashdot readers confuse nuclear power generation with nuclear engines. There is obviously a significant difference and that should be noted.
I hate to rain on people's parades but this has nothing to do with launching rockets from the surface of Earth. If you review the website that is linked to it only talks about Nuclear power for NEP (Nuclear Electric Propulsion) via Hall Thrusters. These thrusters generate very minimal levels (less than 1 N) of thrust and are only appropriate for in space travel.
I debated whether or not I should get into this one because it seemed to degenerate into an exercise of bashing JPL and NASA and making some wild pronouncements about what is possible with X amount of money.
NASA and JPL are all part of the large machine that is the federal government. They are also large organization with thousands of employees and I am sure that can you find some who are not too bright. You will also find incredibly smart and devoted people who would like nothing better than to implement the ideas pushed forward in the Space Act.
Unfortunately I agree with the assessment that the objectives put forward are very aggressive and they would require many things to change in NASA and the US government in general. There are many reasons why this is and if you would like to have a civil discussion about them (i.e. don't tell me that I am stupid and that I should be fired) I would be happy to explain myself (chris@designforward.net).
Suffice it to say that I work for JPL and I spend the majority of my time estimating the cost of space systems, so I have a pretty good idea about what things cost. Without going into the dirty details I would direct your attention to the Mars Pathfinder mission, which landed a 10.5 kg rover on the surface of Mars. The reported cost of the Pathfinder mission was 265 million dollars which works out to be about 25 $M / kg. Now I agree that the costs go down as you increase in size but even at one million dollars per kilo you are still looking at 50 $B for the approximately 50,000 kg that Zubrin proposes. It is also important to note that the Pathfinder was not redundant, was un-manned, and was designed to survive for only 90 days. It was also one of the most efficiently run programs in NASA's history and benefited form years of uncompensated over-time from a devoted group of engineers.
The Space Act is well meaning but asking for these achievements without understanding the level of support they will require will simply get NASA into trouble.
I am not sure what are referring to in your post but Ion engines have been used both by NASA in unmanned exploration and on commercial satellites. Project Prometheus is looking to develope larger, more efficient versions of what is already in common use.
Slashdot Mirror
So... you might want to check your facts. The Americans (Cassini spacecraft) dropped the European Probe (Huygens) on Titan. The press release is somewhat U.S. centric but the first to orbit two separate Planetary bodies is probably a valid claim.
The Deep Space series of spacecraft are technology demonstrations. Some many carry science instruments but the primary focus is to test technologies for use in later missions.
I also believe it was Lockheed Martin who provided the imperial units.
RTG's last a long time but not 50 years. The half life of Plutonium and the degredation of the thermoelectric components will take their toll over time.
The current RTG program called MMRTG (Multi-Mission RTG's) delivers ~120W electric at the begining of life and after 14 years it drops to ~100W electric.
As for MER and the solar panels, the dust build-up is fairly limited.Power problems will probably kill the rovers but it will be the batteries and not the solar cells. Remember that the rovers have Lithium-ion batteries just like your laptop which have high energy density but loose their capacity over time.
Eventually the rover will not be able to store enough power to run the heaters that keep it warm at night and it will freeze.
Yes this is true. However a gas core nuclear reactor is far more likely to become reality than any sort of NTR. This is primarily due to the cost of development which would require a testing facility to ensure that all the exhaust does not escape into the enviroment.
There is nothing wrong with the idea of NTR and in my opinion they are a much better solution than electric propulsion (pick your type). It seemed that both the person who posted this and many slashdot readers confuse nuclear power generation with nuclear engines. There is obviously a significant difference and that should be noted.
But the webpage linked to in the post only discusses a gas core reactor as a power source. I do not see where the NTR concept is discussed.
This is correct when you talk about the electric thrusters (ion or hall). A gas core nuclear reactor is a power source and does not generate thrust.
I hate to rain on people's parades but this has nothing to do with launching rockets from the surface of Earth. If you review the website that is linked to it only talks about Nuclear power for NEP (Nuclear Electric Propulsion) via Hall Thrusters. These thrusters generate very minimal levels (less than 1 N) of thrust and are only appropriate for in space travel.
Well...
I debated whether or not I should get into this one because it seemed to degenerate into an exercise of bashing JPL and NASA and making some wild pronouncements about what is possible with X amount of money.
NASA and JPL are all part of the large machine that is the federal government. They are also large organization with thousands of employees and I am sure that can you find some who are not too bright. You will also find incredibly smart and devoted people who would like nothing better than to implement the ideas pushed forward in the Space Act.
Unfortunately I agree with the assessment that the objectives put forward are very aggressive and they would require many things to change in NASA and the US government in general. There are many reasons why this is and if you would like to have a civil discussion about them (i.e. don't tell me that I am stupid and that I should be fired) I would be happy to explain myself (chris@designforward.net).
Suffice it to say that I work for JPL and I spend the majority of my time estimating the cost of space systems, so I have a pretty good idea about what things cost. Without going into the dirty details I would direct your attention to the Mars Pathfinder mission, which landed a 10.5 kg rover on the surface of Mars. The reported cost of the Pathfinder mission was 265 million dollars which works out to be about 25 $M / kg. Now I agree that the costs go down as you increase in size but even at one million dollars per kilo you are still looking at 50 $B for the approximately 50,000 kg that Zubrin proposes. It is also important to note that the Pathfinder was not redundant, was un-manned, and was designed to survive for only 90 days. It was also one of the most efficiently run programs in NASA's history and benefited form years of uncompensated over-time from a devoted group of engineers.
The Space Act is well meaning but asking for these achievements without understanding the level of support they will require will simply get NASA into trouble.
I am not sure what are referring to in your post but Ion engines have been used both by NASA in unmanned exploration and on commercial satellites. Project Prometheus is looking to develope larger, more efficient versions of what is already in common use.