5 ms·

Could the drone also be used as a means to dedust the rover if it was using solar panels?

ceejayoz 6y ago
I can't imagine the risk of flying in close proximity would be worth it. If you crash into the rover you could jam up the wheels or a piece of scientific equipment. We know from Spirit and Opportunity that dust on the panels isn't much of a concern; wind seems to clear them regularly.
- SamBorick 6y ago
  A large constraint on Spirit and Opportunity was keeping the panels clear, that's why they lasted so long. From what I remember, during martian winter they had to take the grade and the prevailing wind direction into account to keep the dust and fines off. Currently the InSight lander is going into hibernation because the solar panels haven't really gotten cleaned in 3 years: https://www.cnet.com/news/nasa-mars-insight-lander-limits-operations-due-to-dusty-solar-panels/ https://www.cnet.com/news/nasa-mars-insight-lander-limits-op...
  - LunarRover 6y ago
    It's already been three years? Feels like a few months ago. Wow. Still can't believe we've got proof of Marsquakes - that alone turned the consensus on planetary geology upside down.
MengerSponge 6y ago
The dust is electrostatically charged, and the atmosphere is extremely thin. It probably wouldn't help. I imagine a tuned laser could ablate the dust, but that's a very expensive way to recover a solar panel!
jffry 6y ago
The Perseverance rover is using a plutonium-powered radioisotope thermoeletric generator (RTG) this time that I think is rated to provide something like 100 watts for something like 15 years. For the solar panels on the Ingenuity helicopter, it's my understanding that the flights do already help keep them clean. Ingenuity is highly experimental, but even for a future Mars helicopter I doubt they would risk flying it in close proximity to the rover.
- cheschire 6y ago
  > using a plutonium-powered radioisotope thermoeletric generator (RTG) this time that I think is rated to provide something like 100 watts for something like 15 years. Or provide enough heat to keep a stranded botanist warm for a brief cross country drive.
  - aerophilic 6y ago
    Just a note on this: you can’t “increase” the power output of these things. Basically you can imagine these power sources as a “heat pack” that lasts a very long time. So, while you can “store” the energy, and release it later... you can not “use it faster”.
    - ilyagr 6y ago
      As it produces 100W of electricity, the RTG also produces way more energy as heat. According to Wikipedia, the efficiency of an RTG is usually around 3% to 7%, so you get kilowatts of heat. https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_generator https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_... So, it's same order of magnitude to my electric space-heater, if it was stuck to "on". I trust Andy Weir's calculations on whether it is about right to keep a botanist warm on Mars.
      - fiftyfifty 6y ago
        Couldn't you use something like a Stirling engine to create more electricity from the excess heat? You might have to have an external radiator to create a heat gradient with a closed loop of liquid but it certainly seems possible.
        LeifCarrotson 6y ago
        Yes, you could, and you could do better with more moving parts and more stages, but they're optimizing for reliability not for power. In theory, the best you could do is (T_hot - T_cold) / T_hot, or (430 - 210) / 430 ~= 50% , using some approximate values for fin root temperature and Martian climate. To exceed 10% of the theoretical optimum with something that contains no moving parts is pretty impressive, IMO.

I can't imagine the risk of flying in close proximity would be worth it. If you crash into the rover you could jam up the wheels or a piece of scientific equipment. We know from Spirit and Opportunity that dust on the panels isn't much of a concern; wind seems to clear them regularly.

SamBorick 6y ago
A large constraint on Spirit and Opportunity was keeping the panels clear, that's why they lasted so long. From what I remember, during martian winter they had to take the grade and the prevailing wind direction into account to keep the dust and fines off. Currently the InSight lander is going into hibernation because the solar panels haven't really gotten cleaned in 3 years: https://www.cnet.com/news/nasa-mars-insight-lander-limits-operations-due-to-dusty-solar-panels/ https://www.cnet.com/news/nasa-mars-insight-lander-limits-op...
- LunarRover 6y ago
  It's already been three years? Feels like a few months ago. Wow. Still can't believe we've got proof of Marsquakes - that alone turned the consensus on planetary geology upside down.

MengerSponge 6y ago

The dust is electrostatically charged, and the atmosphere is extremely thin. It probably wouldn't help. I imagine a tuned laser could ablate the dust, but that's a very expensive way to recover a solar panel!

jffry 6y ago

The Perseverance rover is using a plutonium-powered radioisotope thermoeletric generator (RTG) this time that I think is rated to provide something like 100 watts for something like 15 years. For the solar panels on the Ingenuity helicopter, it's my understanding that the flights do already help keep them clean. Ingenuity is highly experimental, but even for a future Mars helicopter I doubt they would risk flying it in close proximity to the rover.

cheschire 6y ago
> using a plutonium-powered radioisotope thermoeletric generator (RTG) this time that I think is rated to provide something like 100 watts for something like 15 years. Or provide enough heat to keep a stranded botanist warm for a brief cross country drive.
- aerophilic 6y ago
  Just a note on this: you can’t “increase” the power output of these things. Basically you can imagine these power sources as a “heat pack” that lasts a very long time. So, while you can “store” the energy, and release it later... you can not “use it faster”.
  - ilyagr 6y ago
    As it produces 100W of electricity, the RTG also produces way more energy as heat. According to Wikipedia, the efficiency of an RTG is usually around 3% to 7%, so you get kilowatts of heat. https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_generator https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_... So, it's same order of magnitude to my electric space-heater, if it was stuck to "on". I trust Andy Weir's calculations on whether it is about right to keep a botanist warm on Mars.
    - fiftyfifty 6y ago
      Couldn't you use something like a Stirling engine to create more electricity from the excess heat? You might have to have an external radiator to create a heat gradient with a closed loop of liquid but it certainly seems possible.
      - LeifCarrotson 6y ago
        Yes, you could, and you could do better with more moving parts and more stages, but they're optimizing for reliability not for power. In theory, the best you could do is (T_hot - T_cold) / T_hot, or (430 - 210) / 430 ~= 50% , using some approximate values for fin root temperature and Martian climate. To exceed 10% of the theoretical optimum with something that contains no moving parts is pretty impressive, IMO.