Which Ice Giant Mission should be pursued?

[whitelancer64]

Would a dual mission make sense?

Create two identical orbiters, one going to Neptune, the other to Uranus.

How much more expensive would this be than a single orbiter?

Rather than budget "1" it would be budget "1.9"

The majority of costs for space probes are in labor - for fabrication, QA and QC thereof, assembly, and testing. There's not much of an economy of scale for costs-saving by only fabricating two of every part (but it does save -some- money), and doing so duplicates the costs for assembly and testing (but then again lessons learned during assembly and test for one can apply to the other, with some costs savings there).

They might do it anyway, since engineers like to build two of everything in case something gets damaged along the line.

If I were King of the USA, I would direct that two probes be built and one sent to Uranus and the other sent to Neptune. The potential for getting Cassni-levels of science from each is pretty strong, and worth the expense IMO.

[redliox]

Would a dual mission make sense?

Create two identical orbiters, one going to Neptune, the other to Uranus.

How much more expensive would this be than a single orbiter?

Rather than budget "1" it would be budget "1.9"

The majority of costs for space probes are in labor - for fabrication, QA and QC thereof, assembly, and testing. There's not much of an economy of scale for costs-saving by only fabricating two of every part (but it does save -some- money), and doing so duplicates the costs for assembly and testing (but then again lessons learned during assembly and test for one can apply to the other, with some costs savings there).

They might do it anyway, since engineers like to build two of everything in case something gets damaged along the line.

If I were King of the USA, I would direct that two probes be built and one sent to Uranus and the other sent to Neptune. The potential for getting Cassni-levels of science from each is pretty strong, and worth the expense IMO.

That is a potential option according to some charts: either 2 cloned orbiters with identical functions (and probes) or two orbiters with only one having a probe.  Either of those dual options would be excellent except for the matter of cost.

[Blackstar]

This is an amusing discussion.

[Nomadd]

 Neptune, because it's prettier and everybody pronounces the name right.

[Quagga]

With private space launchers now coming into the picture, then the cost for space agencies to do such missions is going to drop significantly.

Unfortunately, the launch costs are a rather small part of the overall cost of such a mission. 

[redliox]

This is an amusing discussion.

Hopefully in a good intellectual way 

I'm sure you're aware how the 4 options I listed are essentially the vanilla choices the Ice Giant scientists are starting with.  With luck ESA, JAXA, ect can assist adding sprinkles in the form of the dual mission options.

[deruch]

Neptune w/Probe.

More like most of the ice giants most of the time.

Also it will save us from an inordinate amount of assinine [sic] humor.

[Hungry4info3]

With only two somewhat well-studied ice giants, how do you know Uranus isn't more representative of what is "normal"?
(can't argue with your last point though!)

[scienceguy]

Regardless that Neptune is a better name, I think the future should be taken into account and Neptune should be chosen first. The main reasons are that Neptune has a moon that has enough gravity that it could conceivably have a human base on it and Neptune has a slightly higher percentage of helium-3 in its atmosphere.

[Star One]

Regardless that Neptune is a better name, I think the future should be taken into account and Neptune should be chosen first. The main reasons are that Neptune has a moon that has enough gravity that it could conceivably have a human base on it and Neptune has a slightly higher percentage of helium-3 in its atmosphere.

The last thing that should be considered in these missions is anything to do with their targets utility concerning vague notions of human exploration.

[Archibald]

We are sending a probe to Uranus - this won't sell well to Congress... 

[JH]

I'm going to have to go for a full up orbiter to Uranus (and hope that ESA officials didn't grow up watching Peanuts).

To be clear, my personal preference would be to send it to Neptune, but I think Uranus is more feasible.

[redliox]

I'm going to have to go for a full up orbiter to Uranus (and hope that ESA officials didn't grow up watching Peanuts).

To be clear, my personal preference would be to send it to Neptune, but I think Uranus is more feasible.

Agreed, both with desiring Neptune but settling for Uranus and opting for the full up Uranus orbiter (I presume you refer to the probe-less option).  Naturally this only refers to the 4 missions options I gave and as considered in the finale of the Ice Giant study.  With luck, ESA will come forward desiring partnership or the American Congress decides to be more generous; if there's any chance of a Neptune mission (even a fly-by so long as it includes a probe) I definitely would say "go for it."  I think for Uranus, especially since it's easier to study from Earth and a better chance for revisiting, taking a probe-less, Juno-like approach would be a great next step; many of the mysteries involving it include the crooked magnetosphere and deep interior which, even without a probe for the atmosphere, an orbiter could handle if provided a splendid instrument suite.

[JH]

Agreed, both with desiring Neptune but settling for Uranus and opting for the full up Uranus orbiter (I presume you refer to the probe-less option).  Naturally this only refers to the 4 missions options I gave and as considered in the finale of the Ice Giant study.  With luck, ESA will come forward desiring partnership or the American Congress decides to be more generous; if there's any chance of a Neptune mission (even a fly-by so long as it includes a probe) I definitely would say "go for it."  I think for Uranus, especially since it's easier to study from Earth and a better chance for revisiting, taking a probe-less, Juno-like approach would be a great next step; many of the mysteries involving it include the crooked magnetosphere and deep interior which, even without a probe for the atmosphere, an orbiter could handle if provided a splendid instrument suite.

My comment about Peanuts meant I was hoping that ESA might chip in a probe in spite of past experience.

[TakeOff]

We are sending a probe to Uranus - this won't sell well to Congress... 

To avoid the embarrassment of that old naming mistake, NASA should use the Latin name of the mythological Greek god Ouranus, which is Caelus.

NASA's acronym department could name the mission:
PRobe Of Caelus Together with Orbiting SpaceCraft for Outer Planet Exploration
-"Sooo, you suggest sending PROCTOSCOPE to Uranus?
-"Yes, and the probe will go all the way in."

[MATTBLAK]

"There aint half been some clever bathtubs..."  (paraphrasing)

[MATTBLAK]

Neptune Orbiter with Triton lander - target it for one of the ice volcanoes. Orbiter with lots of RTGs and plenty of propellant for long life; lander need only use batteries for two or three days of data transmissions. Probe will likely need launch on Vulcan/ACES, Falcon Heavy or maybe even SLS.