what kind of boat will nasa design for the methane sea on the moon Titan

[Boston]

A daring proposal to try to put a "boat" down on a sea of Saturn's moon Titan is about to be submitted to Nasa.

The scientific team behind the idea is targeting Ligeia Mare, a vast body of liquid methane sited in the high north of Saturn's largest moon.

The concept will be suggested to the US space agency for one of its future mission opportunities that will test a novel power system.

It would be the first exploration of a planetary sea beyond Earth.

"It is something that would really capture the imagination," said Dr Ellen Stofan, from Proxemy Research, who leads the study team.

"The story of human exploration on Earth has been one of navigation and seafaring, and the idea that we could explore for the first time an extraterrestrial sea I think would be mind-blowing for most people," she told BBC News.

Dr Stofan, who is also an honorary professor at University College London, has been describing her group's idea here at the American Geophysical Union's (AGU) Fall Meeting, the world's largest annual gathering of Earth scientists.

Low cost

The Cassini mission currently in orbit around Saturn has confirmed the haze-shrouded moon Titan to be an extraordinary place.

Great lakes exist on its surface, fed by rivers that wash down valleys whenever it rains.

In many respects, it resembles Earth and the way it cycles water between the surface and the atmosphere, except in the frigid temperatures of Titan it is not water but liquid hydrocarbons that are in constant circulation.

Scientists got a few brief hours worth of data back from Titan's land surface in 2005 when the Huygens probe touched down in an equatorial region of the moon.

Now a number of those same researchers are desperate to go back for a longer-lived stay, but to investigate this time the huge pools that contain methane, ethane, propane and probably many other types of hydrocarbon (carbon-rich) compounds.

The Titan Mare Explorer (TiME) has already been under study for about two years. It is envisaged as a relatively low-cost endeavour - in the low $400m range.

It could launch in January 2016, and make some flybys of Earth and Jupiter to pick up the gravitational energy it would need to head straight at the Saturnian moon for a splash down in June 2023.

The scientists have a couple of seas in mind for their off-world maritime research vessel. Ligeia Mare and Kraken Mare are both about 500km across.

Earth relevance

The primary objective of the mission would be to determine the precise chemistry of one of these lakes; but also to do meteorology, to help scientists better understand how the "methane-ologic cycle" on Titan actually works.

"The key instrument is a mass spectrometer because you want to know what the lake is made of, but we also want to do things like depth-sounding," said Dr Stofan.

"We suspect from Cassini radar data that the lakes are many metres deep, but we'd love to know the overall shape of the lake basins.

"Other instruments would test different properties of the lake which would give you a handle on how the density of the liquid varied as the craft drifted along."

According to team-member Dr Ralph Lorenz, what we learn from Titan's lakes could be relevant here on Earth.

It would give scientists the opportunity to study shared climate processes at work under very different conditions.

"If we have models that will work on Earth and on Titan then we can be much more confident that those models understand the fundamentals of what's going on," explained the researcher from the Johns Hopkins University Applied Physics Laboratory.

"The photogenic appeal and the mystique of exploring a sea on another world speak for themselves, but there is a genuine practical application to do with the science that will help us address problems here on Earth."

Pictures will be essential, though. The Huygens lander sent back a vista of orange pebbles - one of the most iconic images in Solar System exploration history. A view from the surface of a methane lake, looking towards the shore would be just as amazing.

Nasa and Esa (European Space agency) are currently considering a joint multi-billion-dollar mission to the outer planets, but they have the Jupiter system and not Saturn as their next priority.
Huygens image of Titan (Nasa/Esa)



Huygens pictured icy pebbles

If TiME is to make it off the launch pad it will have to grasp one of the smaller mission opportunities that Nasa periodically offers, such as the one it runs under its Discovery Class programme. Bids for this opportunity will be invited in the coming months.

The agency will be considering mission concepts that can carry an Advanced Stirling Radioisotope Generator (ASRG). This is a plutonium-driven device that produces power far more efficiently than the traditional Radioisotope Thermoelectric Generators (RTGs) used hitherto on space missions, such as on Cassini.

ASRGs would give TiME sufficient energy to support a very capable instrument suite and a direct-to-Earth communications system to get its data home. The generators - TiME would carry two - could conceivably sustain several years of service on the lake surface.

Whatever the outcome of the Discovery competition - and there will be many bids from other mission hopefuls - Dr Lorenz believes the scientific case for going to Titan is compelling, and he envisages the orangey moon becoming a popular destination in the decades ahead.

"I think the range of science questions that there are there, and the methodologies and types of vehicle that we use to address that science, is going to follow very much the Mars model - we'll have one mission building on the success of another and exploring different questions," he told BBC News.

"Hopefully, TiME will just be the first of many exciting missions to Titan."

[narwhal]

Whatever the vessel is, it will have to be lightweight to reduce launch costs, and able to withstand the cold of liquid methane without becoming so brittle it snaps with the first wave. Carbon fiber composite, perhaps?

[hoytedow]

It could carry oxygen as fuel, still internal combustion, except reverse from earth, with methane intake instead of air intake.

[PAR]

I think mixing O2 and any type of combustion engine would just be asking for a spectacular stellar event, in this environment. Besides, it's unlikely they'll deploy a boat, for example, what's the viscosity of methane at this temperature . . .

[eponodyne]

I'm betting a Ness Yole or better, Eun Mara or Grey Seal would be the bees knees. Proven seaworthy design, plenty of load capacity, already has infrastructure designed in to take advantage of local pressure-differential potential energy.

When I was in school, ammonia was the next most likely supporter of life (next to water). Now that methanogens have been discovered (at deep ocean vents), possibly supporting a chain of life and oxydizing hydrogen and methane into oxygen, I could invision pockets of oxygen supporting combustion and explosion or scary alien life forms


We had better be careful to not let any of these get back here.

[Leo Lazauskas]

Originally Posted by Boston

A daring proposal to try to put a "boat" down on a sea of Saturn's moon Titan is about to be submitted to Nasa.

Anticipated and completed by China and ahead of schedule.

Bos, Titan is cold. I looked up -178°C., then I looked up the density of liquid methane - close to half of that of water. Then I looked up Titan weather - hydrocarbon rain, etcetera but the interesting thing is that to get seasonal, dynamic clouds means that there is weather. There's not much gravity. The atmophere is 1.5 times as dense as Earth's. The density of the sea and atmoshere aren't far apart and there is wind. So, dang, I was afraid of this, my take is that the surface of a sea there will look something like a cross between the interface of ooze (drycleaner perc and wax, mostly) and water in a Lava Lamp and the worst Oregon Coast winter storm you can imagine - but monochrome. Calm it down a notch, tho, because it will be raining methane and some nasty stuff probably forming slush ice. Good luck with the boat design!

[ancient kayaker]

You will need to get data on weather and the sea to atmosphere interface. The characteristics of liquid methane combined with a different gravity and higher atmospheric pressure are going to influence wave behavior and the manner in which spray travels. Will there be a need to deal with freezing methane? If so there'll be de-icing considerations.

What kind of equipment the boat will carry? Size, weight, CoG and the kind of stability requirements and exterior access that equipment will impose on boat design.

Importantly, ensure the materials used do not turn out to be toxic to evolving life forms if any. The generator is going to develop heat for a long time, and attract life if there is any present; what are the responsibilities here?

The questions, answers and requirements for this job are going to accumulate chaotically; is there any way a database could be set up to organize this?

[Boston]

I could fire off an e mail to the person mentioned in the article as being in charge of the design team
they might just get a bang out of a few naval architects taking a stab at the design

I bet I at least get some kind of feedback concerning conditions on titan

could be kinda fun to ponder what might work best

[capt vimes]

what kind of boat will nasa design for the methane sea on the moon Titan

a concrete submarine...

[Boston]

something tells me its not going to be a concrete submarine
but it was a good laugh
thanks
went well on a Monday morning

Ild love to see them do something sail powered with wind generators instead of all the high tech crap they typically do

ps
I just "blasted off" a message to NASA asking for the relevant data
should be interesting to see if they respond
there site said it might take a week or two to get back to me
only the government eh
B

[yipster]

boats have been used before by nasa look at the apollo XII emblem for example

allready checked for interest on mountain lake boating on the moon
but some people nowadays dont even know "we" have been on any moon

Very interesting points there AK.
I, for one, am no naval architect. I suspect that there are but several frequenting this entire forum.
I, personally, would shy away from Bose-Einstein condensate seas (not a term used every day - I found it Googling) until they are ready to mine for energy. It depends on how much wind there is there.
In general, NASA is losing credibility because of one, their taking a stance on AGW, and two, the dubious science involved with AGW. If they are that messed up about our climate (In some views), how can they have a grasp of Titan's?
Our government is spending the future's ability to fund learning like this. Might this trip actually happen?

[dskira]

It's nice to take the tax payer money to play around for nothing.
We went to the moon in 1964 I think (slightly latter slightlty earlier), and what? nothing.
A rock from the moon worth now $5
Nasa should be shut down.
But this is my own opinion.
Cheers
Daniel