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I was 10 when Voyager 2 flew by. I was certain trips to Neptune, pictures, and further exploration would become common. And 30 years later, we haven’t gone back

I was 10 when Voyager 2 flew by. I was certain trips to Neptune, pictures, and further exploration would become common. And 30 years later, we haven’t gone back. It’s far, expensive, priorities, and all that. And now enough time has passed I may never see us get there again. sigh

gedy 7y ago
There's hope, the New Horizons to Pluto was much faster, and before that I was _sure_ I'd never live to see Pluto.
- mikeash 7y ago
  If (and it’s still a substantial “if”) SpaceX’s BFR flies and comes close to living up to its promises, I’m hoping we’ll see a renaissance in space probes. With this combination of heavy lift and low cost, probes could be built much larger and substantially cheaper, and be launched on faster trajectories.
  - deleted 7y ago
    [deleted]
- trentnix 7y ago
  The price of that speed is don’t blink or you’ll miss it. We should have something orbiting Neptune, now.
  - ambulancechaser 7y ago
    Why? How should we decide to spend the resources it orbit Neptune? Why not Saturn or Jupiter; why not land on a comet? Why not put a human on the moon again or perhaps spend the money or medical research or nuclear fusion. What about Neptune seems so compelling to you? I would never have thought it an important or memorable goal and just want to hear why Neptune is so alluring.
    - exmadscientist 7y ago
      Because it's a mostly unexplored corner of our solar system. The Voyagers were survey probes: they saw glimpses of a lot of interesting things, but couldn't stick around and solve any of the hard mysteries. (For example, just what is going on with the weather on both Uranus and Neptune? It's weird!) Orbiters such as Galileo, Juno, and Cassini are able to stick around long enough to do deep science. Orbiters for one or both of our ice giants ought to be much higher on our space exploration priority lists than they seem to be.
    - trentnix 7y ago
      Because the 10-year-old me was teased with pictures and mysteries I want answers to. Because it’s so far. Because it can’t see more than a pale dot in my telescope. Because it’s so alien. And because we have been there, done that on everything you mentioned. Perhaps if I’m ever granted the opportunity to present my case before NASA and Congress, I might offer a more well-thought-out explanation. But right now, “because it would be awesome” should suffice.
      - Rebelgecko 7y ago
        Check out the recently proposed Trident mission, and I guess write your congressperson while you're at it
  - Frenchgeek 7y ago
    I wonder how expensive (and feasible) it would be to send a cubesat to low earth orbit then send it to Neptune via solar sails..
    - thombat 7y ago
      Setting aside the feasibility of solar sail propulsion, power will be an enemy: just getting a typical cubesat level of 5W is much harder at Neptune, since Neptune gets just 1/900th the solar flux. By way of comparison: the "Juno" probe produces 486W at Jupiter (solar flux 1/27th of Earth's) from about 72m^2 of solar panels, weighing 340kg. So if similarly scaled 5W at Neptune is about 110kg + 24m^2 of solar panel. And that's assuming that 5W suffices: "New Horizons" has 200W and a 2 metre diameter radio dish, and still took 15 months to download the data from its brief Pluto encounter (although at a slightly greater distance than Neptune's orbit) If you want it to be an orbiter rather than a brief flyby then it needs some way to shed a lot of velocity: either a lengthy rocket burn and/or aerobraking by grazing Neptune's atmosphere. So unfortunately it seems well beyond cubesat terrain: even a "cheap" probe to the outer planets is a large and complex machine.
    - Rebelgecko 7y ago
      You'd probably need a nuclear generator to power the thing. AFAIK solar sails aren't able to slow down, so you'd need another form of propulsion to establish orbit.

gedy 7y ago

There's hope, the New Horizons to Pluto was much faster, and before that I was _sure_ I'd never live to see Pluto.

mikeash 7y ago
If (and it’s still a substantial “if”) SpaceX’s BFR flies and comes close to living up to its promises, I’m hoping we’ll see a renaissance in space probes. With this combination of heavy lift and low cost, probes could be built much larger and substantially cheaper, and be launched on faster trajectories.
- deleted 7y ago
  [deleted]
trentnix 7y ago
The price of that speed is don’t blink or you’ll miss it. We should have something orbiting Neptune, now.
- ambulancechaser 7y ago
  Why? How should we decide to spend the resources it orbit Neptune? Why not Saturn or Jupiter; why not land on a comet? Why not put a human on the moon again or perhaps spend the money or medical research or nuclear fusion. What about Neptune seems so compelling to you? I would never have thought it an important or memorable goal and just want to hear why Neptune is so alluring.
  - exmadscientist 7y ago
    Because it's a mostly unexplored corner of our solar system. The Voyagers were survey probes: they saw glimpses of a lot of interesting things, but couldn't stick around and solve any of the hard mysteries. (For example, just what is going on with the weather on both Uranus and Neptune? It's weird!) Orbiters such as Galileo, Juno, and Cassini are able to stick around long enough to do deep science. Orbiters for one or both of our ice giants ought to be much higher on our space exploration priority lists than they seem to be.
  - trentnix 7y ago
    Because the 10-year-old me was teased with pictures and mysteries I want answers to. Because it’s so far. Because it can’t see more than a pale dot in my telescope. Because it’s so alien. And because we have been there, done that on everything you mentioned. Perhaps if I’m ever granted the opportunity to present my case before NASA and Congress, I might offer a more well-thought-out explanation. But right now, “because it would be awesome” should suffice.
    - Rebelgecko 7y ago
      Check out the recently proposed Trident mission, and I guess write your congressperson while you're at it
- Frenchgeek 7y ago
  I wonder how expensive (and feasible) it would be to send a cubesat to low earth orbit then send it to Neptune via solar sails..
  - thombat 7y ago
    Setting aside the feasibility of solar sail propulsion, power will be an enemy: just getting a typical cubesat level of 5W is much harder at Neptune, since Neptune gets just 1/900th the solar flux. By way of comparison: the "Juno" probe produces 486W at Jupiter (solar flux 1/27th of Earth's) from about 72m^2 of solar panels, weighing 340kg. So if similarly scaled 5W at Neptune is about 110kg + 24m^2 of solar panel. And that's assuming that 5W suffices: "New Horizons" has 200W and a 2 metre diameter radio dish, and still took 15 months to download the data from its brief Pluto encounter (although at a slightly greater distance than Neptune's orbit) If you want it to be an orbiter rather than a brief flyby then it needs some way to shed a lot of velocity: either a lengthy rocket burn and/or aerobraking by grazing Neptune's atmosphere. So unfortunately it seems well beyond cubesat terrain: even a "cheap" probe to the outer planets is a large and complex machine.
  - Rebelgecko 7y ago
    You'd probably need a nuclear generator to power the thing. AFAIK solar sails aren't able to slow down, so you'd need another form of propulsion to establish orbit.