The case for a Titan rover mission

[rlb2]

<font color="orange">As the probe descended, it drifted over a plateau (center of image) and was heading towards its landing site in a dark area (right). From the drift of the probe, the wind speed has been estimated at around 6-7 kilometers (about 4 miles) per hour.<font color="white"><br /><br />http://www.nasa.gov/mission_pages/cassini/multimedia/pia07230.html<br /><br />The winds on Titan at about 4 mph carries much more energy than the equivalent wind-speed on Earth because of the density of the atmosphere. The balloons buoyancy would be much higher on Titan than the Earth so the balloon and dragchute can be made of much heavier duty material.<br /><br /><br /></font></font> <div class="Discussion_UserSignature"> Ron Bennett </div>

 

[igorsboss]

I really like the Windsurfer idea for Titan. The atmosphere is nice and thick, making a balloon workable.<br /><br />I am concerned that heavy tar-like precipitation may collect on the balloon, grounding it. It may be good to outfit the balloon's surface with some kind of heater for melting this stuff off the balloon.<br /><br />Bring a tank of Oxygen along, and burn Titan's methane for fuel.

 

[bobvanx]

>burn Titan's methane<br /><br />A whole world of hydrocarbons, waiting to get pumped and refined, the oil companies are probably wondering how to bring it here... dang, the pipeline would be very long. Oh, and if you <i>did</i> import the fuel to Earth, you'd be burning up oxygen and generating CO2 using new combustibles, actually increasing the net carbon beyond our primordial store.

 

[mikejz]

Of course the other option is if we could figure out how to bring loads of Oxygen to Titan and heat the place up til its nice and toasty.

 

[thermionic]

I would prefer a rover on either Europa or Titan far ahead of a 'manned' mission to Mars. In fact, I think I'll write my Senators about this. I only hope I live long enough to see the results. The idea just gives me chills! /jd

 

[mikejz]

Either day, As far as I know the Saturn Launch window only opens up once every 20 years....

 

[yurkin]

I think I remember reading that a proposal for ESA’s third cornerstone mission in 2020 is a mission to Titan. I don’t know what the details of it are but it might be the first chance to launch a Titan Rover.<br /><br /><font color="yellow"> Saturn Launch window only opens up once every 20 years....</font><br />That’s only if your relying on gravity assists alone. A nuclear-ion drive you should be able to leave whenever you want.<br />

 

[mikejz]

Due to politics It seems safe to bet that no ESA mission will use nuclear.

 

[munkin]

ESA might be squemish about using nuclear propulsion but I hope NASA won't . Cassini has a nuclear generator onboard . . . . nuclear propulsion should be seriously considered for all future orbiter/rover missions to the outer solar system!!!

 

[JonClarke]

Curiously, nobody has mentioned an airship (I think). Titan is one of the best places in the solar system for an airship, dense, atmosphere, low gravity. You do not need to worry about different terrain types, you can hover and lower sensor probes, cruise at different altitudes. Even if the propulsion system fails you can still drift.<br /><br />Nobody has commented on one obvious energy source on Titan - oxygen burned in a methane atmosphere. Internal combustion engines have a very high energy density.<br /><br />What makes people think that ESA would not use nuclear? Many Eurpoean countries use nuclear power extensively, more so than the US. They also would launch either from Kazakhstan or French Guiana,NIMBYs are in short supply in both places.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[bobvanx]

[modest cough] ahem...<br /><br />I pointed out a balloon would be a great rover for Titan, and of course you know there are lots of engineering studies about various airship designs for exploring this world.

 

[rogers_buck]

What you need for Titan is my nuclear hovercraft idea. Basically, have a nuclear heatsource under the hovercraft skirt to flash the fluid/ice and provide lift and vectorable thrust. On Titan, you could let the wind drive you. It would be a wild ride... To stop the hovercraft retract the nuclear heatsource into an insulated compartment and use it to warm the inside of the hovercraft and power your batteries.

 

[JonClarke]

Yes bod, you did say balloon. But an airship would be better, it can steer and hover at will.<br /><br />Hovercraft would work very well, but are tricky things to operate and use lots of power. Mich more than a boar, rover or airship.<br /><br />Jon. <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[nacnud]

I mentioned an airship too <img src="/images/icons/smile.gif" /> I think the skykitten would be a good model to try, from ATGs website...<br /><br /><i>This vehicle, dubbed the “SkyKitten”, proved the key features of the new technology. Aerodynamically highly stable, with low drag and full STOL/VTOL capability, the SkyKitten demonstrated its ability to take off and land equally on land and water, to manoeuvre with total control and autonomy and to anchor itself in “suck-down” mode without need of any ground personnel or equipment...</i><br />

 

[mcbethcg]

I think a lot of people are missing the fact that this thing would not be controlable from earth. Flying things require guidance, especially over unknown terrain and at low altitudes. At this distance, real-time control is impossible.<br /><br />I don't think that our AI capabilities are up to this task.<br /><br />Its one thing to fly drones on earth at high altitude over known terrain, with the possibility of ground support/commands, as we do on earth. Its an entirely different matter to expect a computer program to be able to maneuver an airship, in winds, around unknown alien mountains, landing on its own for samples, etc.<br /><br />

 

[silylene old]

An airship (or baloon), like a boat, would be interesting.<br /><br />But not as interesting as a rover. I want to be touching and feeling the ground, I want to see rocks, close-up! I want to see my track marks, dig trenches, take core samples, even sample puddles of liquids, and put those samples into my GC-MS. I want to see liquid streams from 1m away, not 500m; I want a microscope which can take highly magnified pictures. This is why I prefer a rover.<br /><br />All that said, I do really value the viewpoint from a high elevation. That's why I suggested (at first) a tethered helicopter with a camera. I admit, a tethered baloon, or a 30m extendable mast might accomplish the same goal more easily.<br /><br />An airship has the advantage of the highest possible mobility, something a rover cannot have. Maybe two missions ?? One an airship, one a rover? Could they share the same orbiter for transmitting the data back to Earth? <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[mikejz]

Before we get all about a plan for a Titan rover we need something else: A map. A good (probebly via Radar) map of Titan needs to be made. This will help identify sites of intrest and what sort or missions should be launched. <br /><br />We could be talking about a totally independent rover, or lander-minirover combo, or a ton of other things; all of which must be decided in the content of having a map of Titan.

 

[nacnud]

That’s why I think a JIMO class orbiter is needed for the next mission to Saturn. Depending on the weight limit on the craft you could add various precision landers/rovers/airship-rover combos etc. You then have the ability so scout the surface and launch probes all from the same mission. Unfortunately such a mission would probably need a new HLLV and more money than you can wave stick at.

 

[astrophoto]

If Titan is so mucky as we suspect, a traditional wheeled rover is probably a poor choice. Too easy to get stuck.<br /><br />Some sort of hover-craft or propelled sled might be better, though control becomes an issue.

 

[nacnud]

Skidoo?

 

[spacechump]

How 'bout this guy?<br /><br />http://robotics.jpl.nasa.gov/~behar/JPLTumbleweed.html<br /><br />As flat as it is down there this guy could move around fairly well I assume.

 

[bobvanx]

>>a map<br /><br />Cassini's radar tracks a really narrow strip of Titan on each pass. Is it 1%? Whatever it is, fly-bys have a different geometry than orbital passes. So perhaps that would be a reason to orbit Titan as a final phase of an extended tour.

 

[mikejz]

Mapping it would not be too hard, nor would more probes. Basically for mapping it, you would basically add Megellen up with some RTGs and a heat sheld for aero caputure. I bet it could be done for the same price as MER, less if there are some spare parts from Cassini. <br /><br />Landers/Probes could fly on a bus simular to the Pioneer probes and rely on Cassini for data rely. <br /><br />Of course it all sounds simple. The bigger issue is the problem of launch windows. If we don't want to wait for the launch window to open up every 20 years we have to get more complex. Also because the cheap 'aka gravity assist' rides come along only every 20 years we are biased towards complex missions to squeeze everything out of the window possible. <br /><br /><br />In many ways I think that if we want experence with Titan we should look towards Venus, outside of the 1000 degree difference in tempature, it seems to have many of the same challenges.

 

[JonClarke]

Venus is a good place to gain experience, even though the problems are the opposite of Titan.<br /><br />Repeat missions to Titan will demand some form of nuclear propulsion. We can't keep having missions with 20 year leads times.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[bobvanx]

>>M[a]gell[a]n up with some RTGs<br /><br />Cassini will be functional for a very long time, and already has the RADAR mapping functionality. So the lowest cost mapping mission would use Cassini.<br /><br />The point being, that Saturn is such an interesting system, we'd certainly want to exhaust all ideas of what to look at before we consigned Cassini to an orbital Titan mapping mission. <br /><br />By orbiting Titan at local noon, the filters that see through the smog function best. A good global visual map would get built up, and combined with topography measurements from RADAR, you'd have the asset you'd need to drop in a rover.<br /><br />We could even start planning it <i>now</i>, since the launch windows are so few and far between. If it were a JIMO class project, take two or three landers.