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I'm getting kinda sick of the media putting more & more non-sense in our heads instead of actual news. This is pure fantasy. They can't build nuclear reactors o

I'm getting kinda sick of the media putting more & more non-sense in our heads instead of actual news. This is pure fantasy. They can't build nuclear reactors on Mars! The only reason why they write this article is because the topic "Mars" generates large amounts of views. News shouldn't be a bussiness :(

8draco8 9y ago
Genuine question: If it's possible to use mini nuclear reactors in satellites then why they just can't land that thing somehow on Mars (like they did with Curiosity) and use it on planet surface to power lab?
- dredmorbius 9y ago
  Output, and fuels. Thermoisotopic generators generally rely on plutonium, which is in very low supply, and generate only about 100-200We output AFAIU. That's enough for electronics and comms on a deep-space mission, but doesn't offer a whole lot of surplus power for planetary activity. Among the reasons that lander craft are so slow-moving (they basically manage a slow crawl) is power demands, though other factors, including navigation and stress, are considerations. https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_generator https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_...
  - avar 9y ago
    > plutonium, which is in very low supply. Thermoisotopic generators are a bad idea for general power generation for a colony for other reasons (they're low power, you need a lot of them), but it's not a problem that they're in low supply. That's just because we haven't been making more plutonium recently, because we haven't needed it. We could simply make more.
    - xorfish 9y ago
      Pl-238 is very expensive to produce. We are talking millions/kg.
      - avar 9y ago
        That's a trivial cost when we're talking about sending things to Mars. The Curiosity rover has around 5kg of Pu-238. NASA estimates that restarting production will cost $6M/kg[1]. The total cost of the MSL program is 2.5 billion[2]. That's $30 million out of 2.5 billion, or 1.2%. NASA has also been buying Pu-238 from the Russians at around $1.5 million/kg[3], which would be $7.5 million for Curiosity, or 0.3% of the cost of the program. I'm interested in deep-space exploration (but am no expert), and as far as I can tell the reason the US is running out of Pu-238 has absolutely nothing to do with cost. It's been happening because only NASA has really wanted this, but producing it has been the purview of the military or the DOE. So the issue has been stuck in some bureaucratic nightmare for decades, the only people allowed to produce Pu-238 didn't need it, and NASA couldn't simply spend a crapload of money to pay another agency or branch of the government to restart production due to the way money politics works, even though it was an overall good investment. So rather than simply restart production at a trivial cost compared to what NASA otherwise spends, it's been easier to buy it from Russia. As [1] shows there's now a real possibility that Pu-238 will run out, so the US has restarted production. 1. https://www.nasa.gov/pdf/636900main_Howe_Presentation.pdf https://www.nasa.gov/pdf/636900main_Howe_Presentation.pdf 2. https://en.wikipedia.org/wiki/Mars_Science_Laboratory https://en.wikipedia.org/wiki/Mars_Science_Laboratory 3. http://dailycaller.com/2017/03/28/nasa-wants-to-stop-buying-russian-plutonium/ http://dailycaller.com/2017/03/28/nasa-wants-to-stop-buying-...
        xorfish 9y ago
        The cost wouldn't be trivial for powering a mars colony. I'm sure the demand for a colony would scale pretty fast to 100kW or more. Now we are talking about Billions. So I think that your original point that cost for Pu-238 is not an issue for a colony is wrong. Small reactors are a much better option as a single ton of fuel could supply a colony with a few MW for decades. You just have to make sure that the largest part is less than 37 tons so it can be transported with a Long March 9.
- cortexio 9y ago
  Mini reactors are useless on Mars. The power they generate is waaay to low compared to the money that is needed to bring them there. Also putting nuclear reactors on sattelites almost never happens and is VERY DANGEROUS. It's what the Soviet Union did in the 70s-90s. The last sattelite launched with a nuclear reactor was in 1988. You have to be pretty insane to launch large amounts of nuclear material from earth in a rocket that can randomly explode in our atmosphere.
  - deleted 9y ago
    [deleted]
  - valuearb 9y ago
    U-238 is pretty stable.
- deleted 9y ago
  [deleted]
petre 9y ago
They don't have to build it on Mars. A kilowatt scale nuclear reactor is small and also safer and more portable. The Russians have already sent nuclear powered satellites into space.
- cortexio 9y ago
  Yeah, i used the wrong word there. I meant, "put" instead of "build"
  - Sharlin 9y ago
    Sure they can. That's the whole point! It turns out nuclear reactors scale down surprisingly well.
    - baybal2 9y ago
      Relatively speaking. Burnup ratios go up with size. Unless you do blended fuel-moderator designs which as I know, were never built
      - wbl 9y ago
        Triga counts as one of those iiuc.
- deleted 9y ago
  [deleted]
xorfish 9y ago
> They can't build nuclear reactors on Mars! That's why you build them on earth and transport them to mars. There are some small designs such as the 4MW(el) u-battery that are small enough for a transport.
- cortexio 9y ago
  Read my 2 comments below. Sry for the confusion.

8draco8 9y ago

Genuine question: If it's possible to use mini nuclear reactors in satellites then why they just can't land that thing somehow on Mars (like they did with Curiosity) and use it on planet surface to power lab?

dredmorbius 9y ago
Output, and fuels. Thermoisotopic generators generally rely on plutonium, which is in very low supply, and generate only about 100-200We output AFAIU. That's enough for electronics and comms on a deep-space mission, but doesn't offer a whole lot of surplus power for planetary activity. Among the reasons that lander craft are so slow-moving (they basically manage a slow crawl) is power demands, though other factors, including navigation and stress, are considerations. https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_generator https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_...
- avar 9y ago
  > plutonium, which is in very low supply. Thermoisotopic generators are a bad idea for general power generation for a colony for other reasons (they're low power, you need a lot of them), but it's not a problem that they're in low supply. That's just because we haven't been making more plutonium recently, because we haven't needed it. We could simply make more.
  - xorfish 9y ago
    Pl-238 is very expensive to produce. We are talking millions/kg.
    - avar 9y ago
      That's a trivial cost when we're talking about sending things to Mars. The Curiosity rover has around 5kg of Pu-238. NASA estimates that restarting production will cost $6M/kg[1]. The total cost of the MSL program is 2.5 billion[2]. That's $30 million out of 2.5 billion, or 1.2%. NASA has also been buying Pu-238 from the Russians at around $1.5 million/kg[3], which would be $7.5 million for Curiosity, or 0.3% of the cost of the program. I'm interested in deep-space exploration (but am no expert), and as far as I can tell the reason the US is running out of Pu-238 has absolutely nothing to do with cost. It's been happening because only NASA has really wanted this, but producing it has been the purview of the military or the DOE. So the issue has been stuck in some bureaucratic nightmare for decades, the only people allowed to produce Pu-238 didn't need it, and NASA couldn't simply spend a crapload of money to pay another agency or branch of the government to restart production due to the way money politics works, even though it was an overall good investment. So rather than simply restart production at a trivial cost compared to what NASA otherwise spends, it's been easier to buy it from Russia. As [1] shows there's now a real possibility that Pu-238 will run out, so the US has restarted production. 1. https://www.nasa.gov/pdf/636900main_Howe_Presentation.pdf https://www.nasa.gov/pdf/636900main_Howe_Presentation.pdf 2. https://en.wikipedia.org/wiki/Mars_Science_Laboratory https://en.wikipedia.org/wiki/Mars_Science_Laboratory 3. http://dailycaller.com/2017/03/28/nasa-wants-to-stop-buying-russian-plutonium/ http://dailycaller.com/2017/03/28/nasa-wants-to-stop-buying-...
      - xorfish 9y ago
        The cost wouldn't be trivial for powering a mars colony. I'm sure the demand for a colony would scale pretty fast to 100kW or more. Now we are talking about Billions. So I think that your original point that cost for Pu-238 is not an issue for a colony is wrong. Small reactors are a much better option as a single ton of fuel could supply a colony with a few MW for decades. You just have to make sure that the largest part is less than 37 tons so it can be transported with a Long March 9.
cortexio 9y ago
Mini reactors are useless on Mars. The power they generate is waaay to low compared to the money that is needed to bring them there. Also putting nuclear reactors on sattelites almost never happens and is VERY DANGEROUS. It's what the Soviet Union did in the 70s-90s. The last sattelite launched with a nuclear reactor was in 1988. You have to be pretty insane to launch large amounts of nuclear material from earth in a rocket that can randomly explode in our atmosphere.
- deleted 9y ago
  [deleted]
- valuearb 9y ago
  U-238 is pretty stable.
deleted 9y ago
[deleted]

petre 9y ago

They don't have to build it on Mars. A kilowatt scale nuclear reactor is small and also safer and more portable. The Russians have already sent nuclear powered satellites into space.

cortexio 9y ago
Yeah, i used the wrong word there. I meant, "put" instead of "build"
- Sharlin 9y ago
  Sure they can. That's the whole point! It turns out nuclear reactors scale down surprisingly well.
  - baybal2 9y ago
    Relatively speaking. Burnup ratios go up with size. Unless you do blended fuel-moderator designs which as I know, were never built
    - wbl 9y ago
      Triga counts as one of those iiuc.
deleted 9y ago
[deleted]

xorfish 9y ago

> They can't build nuclear reactors on Mars! That's why you build them on earth and transport them to mars. There are some small designs such as the 4MW(el) u-battery that are small enough for a transport.

cortexio 9y ago
Read my 2 comments below. Sry for the confusion.