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That destroyed zeppelins because there are things they can crash into especially during take off and landing and the winds are strong enough to rip them apart i

That destroyed zeppelins because there are things they can crash into especially during take off and landing and the winds are strong enough to rip them apart it’s not true for Mars. The winds are to weak because of the thin atmosphere and there aren’t that many things to crash into.

Robotbeat 5y ago
But the zeppelin must be much larger for the same mass (and remember buoyancy is ALSO lower in Mars’ gravity).
- deleted 5y ago
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- dogma1138 5y ago
  Same holds true for a helicopter… before ingenuity no one knew if a helicopter could even fly on Mars.
  - Robotbeat 5y ago
    That’s not accurate. You can do math to show a helicopter can fly on Mars. And a helicopter benefits from the lower gravity, which doesn’t help a zeppelin (as buoyancy is also reduced by gravity but lift force is independent of gravity). So even though lift for both a zeppelin and a helicopter include a density term, the zeppelin is about a factor of 3 worse. Since helicopters already outcompete zeppelins on Earth, on Mars where helicopters have a factor of 3 advantage over zeppelins, it’ll have an even harder time. It’s equivalent to a zeppelin at around 100,000 ft at Earth. Possible, but not very practical.
    - dogma1138 5y ago
      It’s not about the math it’s about the engineering, NASA did the maths and a 40m diameter evacuated airship can carry a substantial payload on Mars, we however have no real clue on how to build it from an engineering perspective. If you would’ve asked people 10 years ago about flying helicopters on Mars plenty of them would say it’s not possible not because the math doesn’t work out, but because of what requirements the math spits out. I can do the math for a helicopter for galactic hydrogen, it doesn’t mean engineering can make one. However a vacuum airship on Mars is very much possible, it’s just a heck of an engineering challenge but if you want to get to large payloads not to mention any substantial flight time it’s by far more realistic than a helicopter.
      - Robotbeat 5y ago
        Fine, engineering it is. And 10 years ago, regardless of what random people on the Internet would've said, we still had the technology to do a Mars helicopter (although the optical navigation has improved and become more lightweight, that could've been offloaded to the rover). It has been studied for decades and we've had good enough solar, batteries, and motors 10 years ago. A zeppelin could in principle work on Mars, but it'll be worse than a helicopter, all things being equal. Weather balloons can work fine at those air pressures, but they don't control their position.
        ncmncm 5y ago
        Batteries are better now than 10 years ago. Motors are better than 10 years ago. Solar is better than 10 years ago. Computers are better than 10 years ago. Each is not a huge amount better, but the improvements multiply out.
        Robotbeat 5y ago
        Not more than about 5-10% (at least at state of the art). Computers are the biggest argument, but again that's off-loadable to the rover. Again, if anyone said 10 years ago that a helicopter on Mars was not realistic, then they didn't know what they were talking about (it's funny how people who style themselves skeptics will learn like 5 facts about some place and then crown themselves an expert). I explored a similar but more advanced concept professionally about ~5 years ago.
        ncmncm 5y ago
        0.9^4 = 0.66 34% better, in aviation, may easily make the difference between practical and not. In the case of Ingenuity, it appears to have made the difference between a need for custom SotA vs. COTS kit. What computing could usefully be offloaded to the rover is very limited. Compressing video, maybe, and that just for power budget. I think Ingenuity has >10x MIPS than Perseverence.
        5y ago

Robotbeat 5y ago

But the zeppelin must be much larger for the same mass (and remember buoyancy is ALSO lower in Mars’ gravity).

deleted 5y ago
[deleted]
dogma1138 5y ago
Same holds true for a helicopter… before ingenuity no one knew if a helicopter could even fly on Mars.
- Robotbeat 5y ago
  That’s not accurate. You can do math to show a helicopter can fly on Mars. And a helicopter benefits from the lower gravity, which doesn’t help a zeppelin (as buoyancy is also reduced by gravity but lift force is independent of gravity). So even though lift for both a zeppelin and a helicopter include a density term, the zeppelin is about a factor of 3 worse. Since helicopters already outcompete zeppelins on Earth, on Mars where helicopters have a factor of 3 advantage over zeppelins, it’ll have an even harder time. It’s equivalent to a zeppelin at around 100,000 ft at Earth. Possible, but not very practical.
  - dogma1138 5y ago
    It’s not about the math it’s about the engineering, NASA did the maths and a 40m diameter evacuated airship can carry a substantial payload on Mars, we however have no real clue on how to build it from an engineering perspective. If you would’ve asked people 10 years ago about flying helicopters on Mars plenty of them would say it’s not possible not because the math doesn’t work out, but because of what requirements the math spits out. I can do the math for a helicopter for galactic hydrogen, it doesn’t mean engineering can make one. However a vacuum airship on Mars is very much possible, it’s just a heck of an engineering challenge but if you want to get to large payloads not to mention any substantial flight time it’s by far more realistic than a helicopter.
    - Robotbeat 5y ago
      Fine, engineering it is. And 10 years ago, regardless of what random people on the Internet would've said, we still had the technology to do a Mars helicopter (although the optical navigation has improved and become more lightweight, that could've been offloaded to the rover). It has been studied for decades and we've had good enough solar, batteries, and motors 10 years ago. A zeppelin could in principle work on Mars, but it'll be worse than a helicopter, all things being equal. Weather balloons can work fine at those air pressures, but they don't control their position.
      - ncmncm 5y ago
        Batteries are better now than 10 years ago. Motors are better than 10 years ago. Solar is better than 10 years ago. Computers are better than 10 years ago. Each is not a huge amount better, but the improvements multiply out.
        Robotbeat 5y ago
        Not more than about 5-10% (at least at state of the art). Computers are the biggest argument, but again that's off-loadable to the rover. Again, if anyone said 10 years ago that a helicopter on Mars was not realistic, then they didn't know what they were talking about (it's funny how people who style themselves skeptics will learn like 5 facts about some place and then crown themselves an expert). I explored a similar but more advanced concept professionally about ~5 years ago.
        ncmncm 5y ago
        0.9^4 = 0.66 34% better, in aviation, may easily make the difference between practical and not. In the case of Ingenuity, it appears to have made the difference between a need for custom SotA vs. COTS kit. What computing could usefully be offloaded to the rover is very limited. Compressing video, maybe, and that just for power budget. I think Ingenuity has >10x MIPS than Perseverence.
        5y ago