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I love this mission. From a science point of view it’s probably good to send similar and well tested rovers to Mars. But to me it gets boring. I think NASA use

I love this mission. From a science point of view it’s probably good to send similar and well tested rovers to Mars. But to me it gets boring. I think NASA used to get a lot of fascination from doing the seemingly impossible like flying to the moon. So I think a mission like this will be fascinating for a lot of people. Also it may spawn off a lot of technology. I hope for a submarine mission to Europa.

Robotbeat 7y ago
I think a flying mission is actually superior to a rover as it can cover far more ground and reach some sites that wouldn't be feasible for a rover. And Titan is uniquely suited to using flight to explore as its gravity is a factor 7.25 lower and its atmosphere a factor of 4.4x denser. That means it's about 30 times easier to hover and covering the same distance is at least 7 times as efficient as on Earth, besides having lower terminal velocity. Even this relatively "inefficient" quadcopter (8 rotor) design could cover dozens of miles (~60km, more than any Mars rover has ever done in its entire mission) in a single hop (which could be recharged by the MMRTG in a single week-long night), although prudence suggests shorter hops at first. That means in principle over its ~10 year lifespan (assuming it can last as long as Cassini did...) it could nearly circumnavigate the entire planet (diameter of ~5000km, day period of about 16 Earth days) while visiting dozens of sites. Granted, range will likely be much more modest as the mission operators will be focusing on not losing this valuable asset, but it shows just how powerful the ability to fly could be. It can visit more sites than all the surface robotic missions to Mars combined. In that sense, it's a fantastic scientific value. And I think the public will absolutely love it. Information from the Dragonfly proposal document: http://dragonfly.jhuapl.edu/News-and-Resources/docs/34_03-Lorenz.pdf http://dragonfly.jhuapl.edu/News-and-Resources/docs/34_03-Lo...
- jvanderbot 7y ago
  This is why theres a helicopter going to Mars.
  - Robotbeat 7y ago
    Indeed... although on Mars it's about 15 times harder to hover than Earth due to the 50x lower atmospheric density.
- maxxxxx 7y ago
  I would guess you can't take much instrumentation on a drone so a rover has advantages there. Anyway, I am excited about this.
  - Robotbeat 7y ago
    Same order of magnitude, actually. Dragonfly is about half the mass of MSL, and because it's so easy to hover, it can have a pretty decent scientific payload. A rover with an arm can more easily approach specific rocks and sample them, though. But Titan is a very mysterious world that we can't get a super good look at from orbit (and which we've barely even glimpsed on the surface), so being able to fly around to many sites is going to be very helpful. Titan has some really interesting and varied geography, too, so the pictures are going to be really cool.
    - maxxxxx 7y ago
      Damn! That's a BIG drone. Should have read closer but now I see 450kg. MSL is like a small car.
- cheerlessbog 7y ago
  > over its ~10 year lifespan (assuming it can last as long as Cassini did...) Cassini wasnt exposed to solvents, rocks and didn't have moving parts (at least not to keep it aloft). Have they made a public statement about lifespan?
  - Robotbeat 7y ago
    Yes, the planned mission time is 2.7 years. MMRTG should provide sufficient power for at least 8 years.
- pfarnsworth 7y ago
  Isn't there wind on Titan?

Robotbeat 7y ago

I think a flying mission is actually superior to a rover as it can cover far more ground and reach some sites that wouldn't be feasible for a rover. And Titan is uniquely suited to using flight to explore as its gravity is a factor 7.25 lower and its atmosphere a factor of 4.4x denser. That means it's about 30 times easier to hover and covering the same distance is at least 7 times as efficient as on Earth, besides having lower terminal velocity. Even this relatively "inefficient" quadcopter (8 rotor) design could cover dozens of miles (~60km, more than any Mars rover has ever done in its entire mission) in a single hop (which could be recharged by the MMRTG in a single week-long night), although prudence suggests shorter hops at first. That means in principle over its ~10 year lifespan (assuming it can last as long as Cassini did...) it could nearly circumnavigate the entire planet (diameter of ~5000km, day period of about 16 Earth days) while visiting dozens of sites. Granted, range will likely be much more modest as the mission operators will be focusing on not losing this valuable asset, but it shows just how powerful the ability to fly could be. It can visit more sites than all the surface robotic missions to Mars combined. In that sense, it's a fantastic scientific value. And I think the public will absolutely love it. Information from the Dragonfly proposal document: http://dragonfly.jhuapl.edu/News-and-Resources/docs/34_03-Lorenz.pdf http://dragonfly.jhuapl.edu/News-and-Resources/docs/34_03-Lo...

jvanderbot 7y ago
This is why theres a helicopter going to Mars.
- Robotbeat 7y ago
  Indeed... although on Mars it's about 15 times harder to hover than Earth due to the 50x lower atmospheric density.
maxxxxx 7y ago
I would guess you can't take much instrumentation on a drone so a rover has advantages there. Anyway, I am excited about this.
- Robotbeat 7y ago
  Same order of magnitude, actually. Dragonfly is about half the mass of MSL, and because it's so easy to hover, it can have a pretty decent scientific payload. A rover with an arm can more easily approach specific rocks and sample them, though. But Titan is a very mysterious world that we can't get a super good look at from orbit (and which we've barely even glimpsed on the surface), so being able to fly around to many sites is going to be very helpful. Titan has some really interesting and varied geography, too, so the pictures are going to be really cool.
  - maxxxxx 7y ago
    Damn! That's a BIG drone. Should have read closer but now I see 450kg. MSL is like a small car.
cheerlessbog 7y ago
> over its ~10 year lifespan (assuming it can last as long as Cassini did...) Cassini wasnt exposed to solvents, rocks and didn't have moving parts (at least not to keep it aloft). Have they made a public statement about lifespan?
- Robotbeat 7y ago
  Yes, the planned mission time is 2.7 years. MMRTG should provide sufficient power for at least 8 years.
pfarnsworth 7y ago
Isn't there wind on Titan?