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NASA plans to launch a spacecraft to Titan

theatlantic.com

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Re: NASA plans to launch a spacecraft to Titan

#41

Post by mikeash »

p1mrx wrote: post #28
rzimmerman wrote: post #4

A flying drone is a really solid idea for a Titan lander for a couple reasons: * The surface atmosphere density is higher than Earth's (1.5 atm) * Gravitational force is much lower (0.15g) * We don't know a lot about the surface composition or topography, so wheels and motors represent a challenge * Visibility may be poor, making visual navigation tricky (though that's also a problem for a flying vehicle I suppose) I…

Will this be the first-ever instance of nuclear-powered flight?

Depends on your criteria, I suppose. https://en.wikipedia.org/wiki/Operation_Plumbbob#Propulsion_...

Re: NASA plans to launch a spacecraft to Titan

#42

Post by Rooster61 »

droithomme wrote: post #32

Venus and Titan have in common that probes landing there tend to only operate a few minutes before failing due to the extreme conditions. A helicopter sounds great, but perhaps it would make sense to try to simply make a probe that can stay alive there long enough to do anything other than send a couple pictures back.

> Venus and Titan have in common that probes landing there tend to only operate a few minutes before failing due to the extreme conditions.

Venus, definitely. Titan though? Huygens is the only probe that's ever touched down there, and it's operational life was tied to its battery life and the fact that Cassini wouldn't be around very long to listen to it. Cassini was on a flyby trajectory, not an orbit around Titan, so as soon as the orbiter went over the horizon, that was it. Outfitting Huygens with enough power to stay on for future flybys would require MUCH more power, a job for which only an RTG would be appropriate since solar is out of the question that far out/under that atmosphere, and batteries just flat out don't last that long.

Nothing about the moon itself prevented a long operational life.

Re: NASA plans to launch a spacecraft to Titan

#43

Post by dflock »

pier25 wrote: post #12
hughes wrote: post #5

It's interesting that there is no existing (or planned) launch vehicle that could perform a direct injection for this mission. Getting to Saturn is really, really hard, and without multiple gravity assists from the inner solar system it would be simply impossible. Too bad it results in an 11 year transit time though! Flying direct would save almost 8 years of that...

> Getting to Saturn is really, really hard Why is that?

https://www.reddit.com/r/space/comments/1ktjfi/deltav_map_of...

Re: NASA plans to launch a spacecraft to Titan

#44

Post by magnamerc »

cwkoss wrote: post #17
rzimmerman wrote: post #4

A flying drone is a really solid idea for a Titan lander for a couple reasons: * The surface atmosphere density is higher than Earth's (1.5 atm) * Gravitational force is much lower (0.15g) * We don't know a lot about the surface composition or topography, so wheels and motors represent a challenge * Visibility may be poor, making visual navigation tricky (though that's also a problem for a flying vehicle I suppose) I…

In addition to lack of solar energy, I wonder if nuclear power source is necessary to keep batteries or other electronics warm enough to function properly. Conversely, on Titan, we won't need to worry about heat sinks as everything is kept at ~94K in a bath of liquid and frozen methane. Perhaps in a few hundred years AWS's most popular region for intensive compute will be under Titan's methane sea. High spin up cost,…

I find it kind of funny that you think AWS will still be around in a hundred years.

Re: NASA plans to launch a spacecraft to Titan

#45

Post by dflock »

QuotedForTruth wrote: post #19
hughes wrote: post #5

It's interesting that there is no existing (or planned) launch vehicle that could perform a direct injection for this mission. Getting to Saturn is really, really hard, and without multiple gravity assists from the inner solar system it would be simply impossible. Too bad it results in an 11 year transit time though! Flying direct would save almost 8 years of that...

Even spaceX's starship/BFR with LEO refuel wouldn't work?

The delta-v required for a trip to Titan, according to this[1], is 28.43 km/s. Optimistically, a fully re-fuelled startship in LEO has ~10km/s of delta-v to spend, afaik.

[1](https://www.reddit.com/r/space/comments/1ktjfi/deltav_map_of...)

Re: NASA plans to launch a spacecraft to Titan

#47

Post by nickserv »

sandworm101 wrote: post #33
p1mrx wrote: post #28

Earlier quoted context omitted.

Will this be the first-ever instance of nuclear-powered flight?

No. >> The Pentagon is aware of a Russian test of a nuclear-powered cruise missile but the system is still under development and had crashed in the Arctic in 2017.[17][18][19] A RAND Corporation researcher specializing in Russia said "My guess is they're not bluffing, that they've flight-tested this thing. But that's incredible." https://en.wikipedia.org/wiki/Nuclear-powered_aircraft#Russi... https://en.wikipedia.org…

This case is different though, using the fission reaction to generate electricity which in turn powers the electric motors among other things.

The nuclear powered missiles use the fission reaction to heat incoming air similar to how a jet engine works.

Re: NASA plans to launch a spacecraft to Titan

#48

Post by binarymax »

rzimmerman wrote: post #4

A flying drone is a really solid idea for a Titan lander for a couple reasons: * The surface atmosphere density is higher than Earth's (1.5 atm) * Gravitational force is much lower (0.15g) * We don't know a lot about the surface composition or topography, so wheels and motors represent a challenge * Visibility may be poor, making visual navigation tricky (though that's also a problem for a flying vehicle I suppose) I…

How does one test on earth, a drone for a different atmospheric and gravitational environment? Some great drone simulation techniques are going to come out of this project.

Re: NASA plans to launch a spacecraft to Titan

#49

Post by mdorazio »

rzimmerman wrote: post #4

A flying drone is a really solid idea for a Titan lander for a couple reasons: * The surface atmosphere density is higher than Earth's (1.5 atm) * Gravitational force is much lower (0.15g) * We don't know a lot about the surface composition or topography, so wheels and motors represent a challenge * Visibility may be poor, making visual navigation tricky (though that's also a problem for a flying vehicle I suppose) I…

I kind of wish it had an airship counterpart. Inflating a dirigible there would take advantage of the same atmosphere + gravity benefits with the added bonus of not needing constant power to move around.

Re: NASA plans to launch a spacecraft to Titan

#50

Post by nickserv »

LordLotherak wrote: post #46

NASA is really good at planning future missions. Implementing them? I've heard hundreds of fantastical half-baked ideas and very few of them materialize over the course of my 46 years on earth.

Their robotic programs are generally great successes though - Mars rovers, Saturn, Pluto for the most recent achievements. Incredible stuff, and unmatched.

Probably because the senate keeps their corrupt hands off of these types of missions.

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