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No. It's very hard to go fast, and to get to Neptune, you need to burn a lot of fuel to get there. Getting home needs a whole lot more fuel too. Space travel is

No. It's very hard to go fast, and to get to Neptune, you need to burn a lot of fuel to get there. Getting home needs a whole lot more fuel too. Space travel is hard. You can go with lower energy transfer orbits, and wait forever to get there, or you can go high-speed and carry a ton of fuel with you.

eesmith 4y ago
Getting home requires no additional fuel if using a free-return trajectory and you don't want to be there for long. Jones, Drew Ryan, 2016, "Trajectories for flyby sample return at Saturn's moons", https://hdl.handle.net/2014/46163 https://hdl.handle.net/2014/46163, Root, V1 at https://dataverse.jpl.nasa.gov/file.xhtml?fileId=53873&version=1.0 https://dataverse.jpl.nasa.gov/file.xhtml?fileId=53873&versi... > Here an alternative and novel mission concept is analyzed to return a sample from either Titan or Enceladus, without capturing at Saturn. Instead, ballistic free return trajectories are sought which also incur a close encounter of the icy moon. The spacecraft could sample a plume (or upper atmosphere) during the hyperbolic flyby. The time frames are on the order of 20 years. OTOH, you would only have a few dozen hours near the planet. ("This 16 year mission, has the Titan flyby occurring about 10 hours prior to Saturn closest approach").
gpm 4y ago
If you plot your trajectory so that you will just slightly in front of neptune, shouldn't you be able to use it's gravity to slingshot you back towards the inner solar system? I'm skeptical that it's worth it... because higher powered radios just aren't that expensive, but it's not obviously (to me) impossible either. Actually capturing your probe back in earth orbit... probably would be prohibitively expensive. But it seems like you could at least get it close by for a shorter communication distance.
- Sharlin 4y ago
  At the speeds needed to reach the outer Solar System in the first place, you would need to intersect the planet's surface (atmosphere, whatever) to get anywhere near the slingshot effect needed to throw you back to where you came from. Essentially it would only be possible with a black hole or another anomalously dense object.

eesmith 4y ago

Getting home requires no additional fuel if using a free-return trajectory and you don't want to be there for long. Jones, Drew Ryan, 2016, "Trajectories for flyby sample return at Saturn's moons", https://hdl.handle.net/2014/46163 https://hdl.handle.net/2014/46163, Root, V1 at https://dataverse.jpl.nasa.gov/file.xhtml?fileId=53873&version=1.0 https://dataverse.jpl.nasa.gov/file.xhtml?fileId=53873&versi... > Here an alternative and novel mission concept is analyzed to return a sample from either Titan or Enceladus, without capturing at Saturn. Instead, ballistic free return trajectories are sought which also incur a close encounter of the icy moon. The spacecraft could sample a plume (or upper atmosphere) during the hyperbolic flyby. The time frames are on the order of 20 years. OTOH, you would only have a few dozen hours near the planet. ("This 16 year mission, has the Titan flyby occurring about 10 hours prior to Saturn closest approach").

gpm 4y ago

If you plot your trajectory so that you will just slightly in front of neptune, shouldn't you be able to use it's gravity to slingshot you back towards the inner solar system? I'm skeptical that it's worth it... because higher powered radios just aren't that expensive, but it's not obviously (to me) impossible either. Actually capturing your probe back in earth orbit... probably would be prohibitively expensive. But it seems like you could at least get it close by for a shorter communication distance.

Sharlin 4y ago
At the speeds needed to reach the outer Solar System in the first place, you would need to intersect the planet's surface (atmosphere, whatever) to get anywhere near the slingshot effect needed to throw you back to where you came from. Essentially it would only be possible with a black hole or another anomalously dense object.