Linked Questions

17
votes
2answers
5k views

Why there is no orbiter for Uranus or Neptune?

In the 21st century, why is there is no orbiter for Uranus or Neptune or at least their moons? It would definitely tell us more about the structure and composition of these planets. I know it must ...
20
votes
2answers
1k views

What types of sustainable energy are available beyond Mars?

Most of the energy we use on Earth in our daily activities is a derivative of solar; wind, hydroelectric, coal, gas (oil), wood fire, solar cells. While we might not think about it, all of these are ...
15
votes
2answers
3k views

Why does Curiosity use an RTG rather than solar (as Spirit and Opportunity do) for power?

Why did Curiosity choose to go with nuclear power? While solar panels have issues with Martian dust, this was a known factor before the 2004 Spirit and Opportunity mission. Why then did the 2004 ...
18
votes
2answers
3k views

How far from the Sun can solar power be used as a reliable energy source?

Space probes headed for the far reaches of our Solar System rely on radioisotope thermoelectric generators for power (Cassini–Huygens, Voyager 1, Voyager 2). Presumably this is because solar power ...
15
votes
1answer
1k views

How does the launch risk for a plutonium RTG and a uranium fission reactor compare?

I was looking at this answer that talks about how a good alternative to Radioisotope Thermoelectric Generators would be fission reactors. It makes a number of good points, but in the comment thread ...
9
votes
4answers
442 views

How will Yuri Milner and Stephen Hawking's nanobots decelerate and transmit data upon arrival at Alpha Centauri?

Does anyone know what exactly is their plan, once they get there? How is that nano-thing going to slow down / take images / send data back to us? I couldn't find any information on this.
16
votes
2answers
700 views

How does the launch risk posed by plutonium compare to the launch risk posed by propellants?

For outer solar system exploration, virtually the only feasible power subsystem are Radioisotope thermoelectric generators (RTGs). These include plutonium, which may carry considerable risks (see ...
8
votes
2answers
493 views

Which wears out faster on RTGs; the R's or the TG's? (the radioisotopes or the thermocouples)

Below this answer to Are there any safe-to-launch alternatives to RTG's for outer solar system exploration? I saw the comment: ...the Voyager RTG cores are still putting out plenty of heat. The ...
12
votes
1answer
893 views

Is there an alternative to nuclear reactors for high-power spacecraft?

Many of my favorite ideas for space exploration, such as large outer solar system probes, or the Mars Direct human Mars exploration proposal, require nuclear reactors to supply the high-power ...
9
votes
3answers
370 views

Alternative energy sources for inter-stellar probes?

Are there any alternative energy sources to power inter-stellar probes such as Voyager I and II developed or in development by any space agency? Plutonium (238-Pu) has a half-life of about 87,7 years,...
3
votes
2answers
149 views

Was Nuclear battery system not used for Mars Spirit and Opportunity rovers?

Mars Spirit and Opportunity rovers exceeded expectations by working for many years than the planned 90 day mission. But why was Nuclear Battery System not used and Solar panels were used for power ...