Pluto/Charon lander: Good or no good?

[TrainEngie]

If we can land on Mars and Titan, why not Pluto and Charon?

From a Delta-V perspective, the rocket for a Pluto lander might be bigger than the Saturn V.

Well, communications for a lander would be lengthy (New Horizons took a long time to upload its history-making pics)

So, Pluto lander or not?

[SargeRho]

Once we have nuclear-electric propulsion systems, sure, why not. Currently it would take an absurdly large rocket to pull it off.

[Mitchz95]

A lander would be awesome, but it would be pretty delta-v heavy. You'd need a lot of gravity assists to make it happen.

[Superfluous J]

I would rather send 100 probes to other targets.

Okay probably not 100. But however many we can get for what it would cost for a Pluto lander.

[NFUN]

The question is too vague to be useful. Of course eventually we'd want a Pluto lander, but not for the near future. Like 5thHorseman said, I'd prefer many other missions first, so I said no to the poll, but why wouldn't we want a lander once we could do it cheaply without sacrificing other missions?

[SargeRho]

A pluto lander would be a perfect payload for a precursor/prototype of an interstellar probe. Show that whatever design you choose can put a large payload across large distances, by sending a large science lander to pluto and charon?

[ChrisSpace]

If we are using non-chemical propulsion to get there, i'd definitely support it.

[Thomassino]

There are some places where we should land firstly. For example Europa, Enceladus, Titan's hydrocarbon lakes etc. If space agencies had an unlimited budget, sure, why not land on Pluto? But money are serious issue and Pluto is, well, only a frozen ball of ices.

I seriously doubt something else than NH will visit Pluto within our lifetimes.

[Rath]

There are some places where we should land firstly. For example Europa, Enceladus, Titan's hydrocarbon lakes etc. If space agencies had an unlimited budget, sure, why not land on Pluto? But money are serious issue and Pluto is, well, only a frozen ball of ices.

I seriously doubt something else than NH will visit Pluto within our lifetimes.

This is why I hope we have a asteroid scare to swing public opion in favor of the space program. Like a city-killer rock skipping off the atmosphere.

EDIT: It would need to be one that would end up hitting the USA though. Hopefully some little fragments would hit the ground to shut up the denialists.

Now, back on topic. Yeah, cool but just launch a few submarine probes at all those moons that might have life for the cost of a pluto lander.

Edited September 28, 2015 by Rath

[AbhChallenger]

By the time we have the technology to send a lander within a reasonable time (Look at how long it took NH to get there even with its high speed) we mise well send astronauts there.

There are still discoveries being made by scientists going over the voyager data again and again. I suspect we will still hear about discoveries made from NH data alongside news of the first humans on Mars. So it is not like the scientists will have nothing to do.

Going there with traditional chemical rockets is a complete non starter.

[cptdavep]

I think if we're blowing that amount of delta v on something we'd be better off doing a flyby of Sedna, it's on closest approach of its huuuge orbit in the next few decades and it's a rare opportunity to study something from so far out, which maybe even captured from interstellar space. Or maybe Uranus or Neptune systems deserve Casini style orbiters as we know very little about them.

[andrewas]

This is why I hope we have a asteroid scare to swing public opion in favor of the space program. Like a city-killer rock skipping off the atmosphere.

We had a city killer in Chelyabinsk - it airburst and the shock smashed ever window in the city. Thousands of injuries, millions of dollars damage, and if it had impacted intact it would have been about 500kt, easily enough to erase a city from existence.

A couple of years later, no one remembers it.

[CalculusWarrior]

A pluto lander would be a perfect payload for a precursor/prototype of an interstellar probe. Show that whatever design you choose can put a large payload across large distances, by sending a large science lander to pluto and charon?

There is at the very least an entire order of magnitude of difficulty between landing a payload on Pluto to actually sending a probe to another star.

[cryogen]

The problem is that Pluto has little gravity (v_esc = 1.2 km/s), so the Oberth effect gives you no help with capturing into orbit. Any realistic trajectory arrives at Pluto with a very high v_inf, and all of that has to be cancelled with propulsive delta-v.

New Horizons' flyby was at a relative speed of 11 km/s, which would be impossible for chemical propulsion to cancel. If you work out the orbit equations, more realistic speeds would give you ridiculously long flight times, like 30-50 years!

What you'd need is high-Isp propulsion to decelerate to Pluto from a high v_inf. Since this happens very far from the sun, you need nuclear or radioisotope propulsion.

"Kuiper Belt Object Orbiter Using Advanced Radioisotope Power Sources and Electric Propulsion"

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20110014485.pdf

"PRELIMINARY DESIGN OF AN ADVANCED MISSION TO PLUTO"

http://www.esa.int/gsp/ACT/doc/PRO/ACT-RPR-PRO-ISTS2004-Pluto.pdf

There's a couple design studies for Pluto/Kuiper orbiters. I'd guess a lander wouldn't be much more difficult, given the low gravity. But there's very little payload mass to work with, so it'd have to be tiny.

[TABLE=width: 800]

[TR]

[TD][/TD]

[TD][/TD]

[TD][/TD]

[/TR]

[TR]

[TD][/TD]

[TD]NASA GRC / JPL[/TD]

[TD]ESA[/TD]

[/TR]

[TR]

[TD]mass[/TD]

[TD]3,172 kg wet (130 kg science payload)[/TD]

[TD]830 kg wet (19.3 kg science payload)[/TD]

[/TR]

[TR]

[TD]launch[/TD]

[TD]Delta IV Heavy + Star 63-F, 70 km²/s²[/TD]

[TD]Ariane V, 100 km²/s²[/TD]

[/TR]

[TR]

[TD]gravity assists[/TD]

[TD]Jupiter[/TD]

[TD]Jupiter[/TD]

[/TR]

[TR]

[TD]tof[/TD]

[TD]16 years[/TD]

[TD]16 years[/TD]

[/TR]

[TR]

[TD]power[/TD]

[TD]9x 550 W Stirling generators (4,950 W)[/TD]

[TD]4x 300 W GPHS-RTG (1,200 W)[/TD]

[/TR]

[TR]

[TD]fuel[/TD]

[TD]54x GPHS (23.4 kg Pu-238; 13,200 W heat)[/TD]

[TD]72x GPHS (31.2 kg Pu-238; 17,600 W heat)[/TD]

[/TR]

[TR]

[TD]gridded ion engines[/TD]

[TD]1+1 redundant NEXT (Isp = 3,327 s)[/TD]

[TD]2+2 redundant QinetiQ T5 (Isp = 4,500 s)[/TD]

[/TR]

[/TABLE]

Edited September 27, 2015 by cryogen

[_Augustus_]

SLS Block II could probably deliver a small lander and nuclear-powered tug...

[Bill Phil]

SLS Block II could probably deliver a small lander and nuclear-powered tug...

Possibly, yes.

[lajoswinkler]

It would be cool, but to pull it off using chemical rockets? Won't happen.