Slashdot is powered by your submissions, so send in your scoop

 


Forgot your password?
Close
typodupeerror
×
Space NASA

Proposed NASA Mission Would Sail the Seas of Titan 197

Posted by kdawson from the can-the-sirens-be-far-behind dept.
The BBC has a report on a proposal that will be submitted to NASA for funding — a mission to Saturn's moon Titan that would deposit a lander on its hydrocarbon sea. (We recently discussed the widely-circulated photo of sunlight glinting off one of Titan's seas.) "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. ... '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. ... The Titan Mare Explorer (TiME) has already been under study for about two years. It is envisaged as a relatively low-cost endeavor — 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."
This discussion has been archived. No new comments can be posted.

Proposed NASA Mission Would Sail the Seas of Titan More

Proposed NASA Mission Would Sail the Seas of Titan

Comments Filter:

  • Sailing the myriad seas? (Score:5, Funny)

    by newcastlejon ( 1483695 ) on Saturday December 19, 2009 @06:29PM (#30501092)

    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

    Oh come on, everyone knows that once you invent satellites the whole map is revealed!

    • Just imagine what'll happen when they circumnavigate Titan and figure out it's actually round!

      • Re: (Score:3, Funny)

        by Tumbleweed ( 3706 )

        Just imagine what'll happen when they circumnavigate Titan and figure out it's actually round!

        So is a pizza. That doesn't mean it isn't also flat. Titan could be the same way. They always warn you about falling off the edge - but what if something comes FROM off the edge?! Didn't think of THAT, DID you?!

        That's right...I went there.

        • I am dissapointed this did not come from the pizza anology guy...

          • I am dissapointed this did not come from the pizza anology guy...

            Hush up, you. You got what you paid for.

        • Re: (Score:3, Interesting)

          by mangu ( 126918 )

          Or it could be like a Swiss cheese: round, flat, and hollow at the same time.

    • Re: (Score:3, Insightful)

      by msauve ( 701917 )
      Your point is correct. "The story of human exploration" and seafaring was purposed on finding the distant shore, and what was there. On Earth, other than finding new life forms, the surface of the sea is pretty uninteresting. For a space mission, you can go to that distant shore directly. Not much chance of finding life in a sea of methane (and if there were life, you'd expect it to be everywhere in that sea).

      Other than providing a gimmick to make this different than previous missions, what's the point? L

      • Re: (Score:3, Interesting)

        by SleepingWaterBear ( 1152169 )

        Well, conditions on the earth vary dramatically with location, even ignoring biological and biogenic variation. It seems to me that a vessel capable of performing tests over a wider area can't help but provide better data. One of the big downsides of the Mars rovers is that they're restricted to such a small portion of the planet's surface, especially since for the Titan mission this can apparently be achieved on a low budget. I mean, what reason do we have to think that the chemical composition of the o

      • Re:Sailing the myriad seas? (Score:5, Interesting)

        by FiloEleven ( 602040 ) on Saturday December 19, 2009 @08:20PM (#30501566)

        There are a number of good reasons for doing this.

        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.

        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."

        Plus it's already been under study for two years, and it would test a "novel power system," the Advanced Stirling Radioisotope Generator.

        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.

        Not to mention that Titan looks like one of the best nearby candidates for life, specifically in its seas and not on its surface. Landing on Titan's shores is apt to be far less interesting than in its seas.

      • Re:Sailing the myriad seas? (Score:4, Insightful)

        by thrawn_aj ( 1073100 ) on Saturday December 19, 2009 @09:13PM (#30501764)

        Other than providing a gimmick to make this different than previous missions, what's the point? Land something in a sea of methane and look for what? Sail around to find more liquid methane?

        You're probably right. Aw hell, scratch the 'probably'. Speaking purely personally though, this is the first time in the past 10 years I've actually felt a stirring in my heart about space exploration. This Titan thing actually brought back some of the magic of space that used to come through so vividly in the science fiction of the 80s (before the post-modernist hacks stank up the place). Huh, let's just say that as a taxpayer, I wouldn't be in the least upset if this mission actually happened. In fact, I'd be out there cheering it on all the way. Go figure :). Guess science is far from unemotional eh?

      • Re:Sailing the myriad seas? (Score:4, Interesting)

        by John Hasler ( 414242 ) on Saturday December 19, 2009 @10:42PM (#30502026) Homepage

        > Sail around to find more liquid methane?

        Sail around and observe thousands of miles of shoreline. Study the atmosphere and seabottom at widely separated points. This ship will travel farther in a day than a Mars rover can in a month.

      • Re: (Score:3, Insightful)

        by Nadaka ( 224565 )

        Navigating by sea is easy and cheap. By targeting the sea, you may be able to visit and study its entire shoreline. If you landed on the shore instead, you are limited to that area you land in.

    • blacksheepwall

    • Do you still have an old Pentium III in the corner that you play that game on?

    • Re: (Score:2, Insightful)

      by aldo.gs ( 985038 )
      The Apollo Program used to reveal cities back in the day :P

    • Arhhh, me lad, I've sailed the seven seas, 'tis time for another.

      Can ye be drinking the sea, I is asking meself?

  • Odds of finding alien life? (Score:5, Funny)

    by gmuslera ( 3436 ) on Saturday December 19, 2009 @06:31PM (#30501108) Homepage Journal
    At least it could find a few sirens.

  • Are any non-profits doing anything like this? (Score:3, Interesting)

    by Anonymous Coward on Saturday December 19, 2009 @06:37PM (#30501134)

    I would seriously be interested in donating maybe a hundred dollars toward something like this, and I can't be the only one. Are there any non-profit organizations that fund similar missions?

  • Titan Landing Probes (Score:5, Interesting)

    by ranson ( 824789 ) on Saturday December 19, 2009 @06:37PM (#30501136) Homepage Journal
    Interestingly enough, the Cassini Orbiter's landing probe, the Huygens, which landed on Titan a few years back, was designed with floatation devices, just in case it hit liquid instead land (ultimately it hit land). An interesting fact about Titan: the high density of the atmosphere, combined with a much lower gravitational force than that of earth results in very soft probe landings. In fact, it is hypothesized that on Titan, a human could strap fake wings on his arms and fly -- now if only we breathed methane and could survive at temperatures colder than -200F...

    • Re:Titan Landing Probes (Score:4, Interesting)

      by MichaelSmith ( 789609 ) on Saturday December 19, 2009 @07:03PM (#30501270) Homepage Journal

      I suppose another way would be to build a balloon borne probe, probably using hydrogen for buoyancy. It could compress the hydrogen to land, and release hydrogen to lift.

    • Re: (Score:2)

      by Tablizer ( 95088 )

      In fact, it is hypothesized that on Titan, a human could strap fake wings on his arms and fly

      No, honey, I haven't gone cookoo; I'm practicing for emergency landings on the Titan mission.
       

    • Re:Titan Landing Probes (Score:5, Interesting)

      by deglr6328 ( 150198 ) on Saturday December 19, 2009 @08:00PM (#30501488)

      What's missing from this discussion, and so far as I can see from any proposal site discussions on this mission, is how to get the data back from the probe! If this is going to be a lander without an orbiter, you have a SERIOUS problem of how to get data back to earth. We talked about this very topic 5 years ago here [slashdot.org] after Huygens landed. People are going to want high-res images, audio and at least some video in addition to all the other basic science data from this mission. That is a HUGE amount of information to get back to earth from a billion miles out, while floating on a lake of CH4 under a thick atmosphere. The Huygens probe had 2 redundant, 8 watt, medium gain (partially directional) on board radio transmitters that sent all the data from the probe through the Cassini orbiter relay system. It took VLBI aperture synthesis, simultaneously using ~20 of some of the largest radio telescopes around the world JUST TO HEAR THE CARRIER SIGNAL of Huygens as it descended on Titan. We couldn't get any actual data directly from Huygens, we couldn't hear modulation of the signal clearly from that far away.

      Huygens had a power budget from its NaS batteries of ~250W, you're not going to do much better than that with a sterling radioisotope generator for this proposed mission. So you have maybe 20W of radio power to use on this mission in order to get all your data back from Titan, you NEED to use a directional (high gain) antenna to do that. How the hell do you accurately and consistently point a high gain antenna directly at earth when rotating and bobbing around wildly while floating over the waves of a Titanian lake?!

      • TFA says this:

        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.

        Would 500W be enough? You seem to know what you're talking about, but I suspect NASA does too. It would be interesting to find out how (and if) they overcame the objections you raise.

        • Actually, someone posted below that the ASRG is rated at 140W, so the total would be 280W. Looks like your power estimate is spot-on.

      • Ah but that discussion talks about phased arrays and even if you need a steerable antenna I suppose thats a lot easier to do these days with microcontrollers and compact servos.

        Indignant antenna designers are invited to contemplate ABM search radars...

        -Arthur C Clarke

        • Re: (Score:2)

          by tftp ( 111690 )

          that discussion talks about phased arrays

          You need to know your orientation and position to control the antenna. On Earth that would be done with GPS augmented with an inertial system when GPS signal is not available. Additionally you need to know the orientation, that can be done (again on Earth) by magnetic compass and by Sun/stars. On Titan there is no GPS, not much is known about its magnetic field (and interference from Saturn is huge,) and astronomy may or may not work depending on how fast the vess

          • Re: (Score:2)

            by sznupi ( 719324 )

            Liquid methane probably also has low viscosity, which makes things worse.

            OTOH the low gravity, small influx of energy and dense atmosphere might mean the seas of Titan are rather calm. BTW, the atmosphere is rather hazy, so there would be indeed a problem with aiming - but perhaps the lander will use strong signals transmitted to it from Earth as a beacon?

            • Re:Titan Landing Probes (Score:4, Interesting)

              by tftp ( 111690 ) on Sunday December 20, 2009 @02:00AM (#30502550) Homepage

              I don't know about the "small influx of energy," that's basically one of objects of research here. The Sun is definitely far away, but Saturn is close, and its gravitational interference should be considerable, so far that Titan is locked in position just as our local Moon is. There are also clouds forming and dissolving, which must influence the weather.

              perhaps the lander will use strong signals transmitted to it from Earth as a beacon?

              Let's say the distance from Earth to Saturn is 10 A.U. (it varies, obviously). That would be 149.60×10^10 meters. The path loss (using the Friis transmission equation [wikipedia.org]) is 300 dB at 30 GHz. Antennas of Deep Space Network give you gain of 80 dB. The antenna on the lander, as a guess, will give you 40 dB at best [wikipedia.org] if it is a fixed parabolic dish. 300 - 80 - 40 = 180 dB (in either direction.) If we transmit from Earth at 1 MW [wikipedia.org], that would be 90 dBm. Then the signal at the front end of the receiver on Titan will be -90 dBm. This is not a problem in itself, modern receivers can work with even smaller signals. A ham receiver (like K3 [elecraft.com]) will detect a signal at -136 dBm within 500 Hz.

              But there is still a problem. High gain antennas have, by definition, a narrow beam. It's like a telescope. But you can't look through a telescope to find a star! Your field of vision is too small. But if you make the beam wider the signal disappears! So here is the catch 22 - you can receive the signal from Earth only if you already know where it is coming from :-) Phased antenna arrays are kind of convenient for beam-forming on the fly, but they are typically not as good as a simple dish (or else we'd all use only them.)

              There may be a way to do it still. First of all, you may make your receiver so good that it will detect the signal even with antenna configured for a wide beam. You only need a few bits per second at that stage. It helps a lot that you are swimming in the sea of cryogenic liquid, you can cool your front stage somewhat - not as He would allow, but still -160C is better than nothing.

              Alternatively, look for a signal with a wide beam, but that signal won't be coming from Earth. Find a stronger signal - from the Sun, or from some pulsars, or from anywhere else that can be used as a good astronomical marker. That assumes that your communication system covers the right frequency band.

              But all in all, it's too much risk for such a trivial [today] problem. Your mission may easily fail just because the lander can't find Earth - and that happened more than once with other probes, it's not unusual. Especially when you don't have a clue what you are landing into. If I were to plan the mission, I'd splurge on a proper set of one orbiter and one or two landers. It's a good distance to Saturn, many years in transit, so you want to make one mission count. Cost should not be such a concern when you are doing the most complex rocket science that there is.

      • Re: (Score:2)

        by Cyberax ( 705495 )

        As usual - beam data to a satellite and then send to Earth,

  • Picture (Score:4, Interesting)

    by MichaelSmith ( 789609 ) on Saturday December 19, 2009 @06:39PM (#30501144) Homepage Journal

    Wikipedia has a picture [wikipedia.org] showing the probe floating on Titan.

    One question I can immediately see an answer to is whether the ASRG [wikipedia.org] generates as much power in vacuum as it will on the surface of Titan. My assumption is that having a weaker heat sink will reduce power output but I can't confirm that.

    • One question I can immediately see an answer to is whether the ASRG [wikipedia.org] generates as much power in vacuum as it will on the surface of Titan. My assumption is that having a weaker heat sink will reduce power output but I can't confirm that.

      On the contrary, a vacuum makes a very poor heat sink. If anything, being immersed in an atmosphere that is as cold as Titan's may lower the effective Tc due to the higher thermal conductivity of the surrounding atmosphere. The lower the Tc, the higher the

      • No thats what I mean. If they use this stirling engine will they get sufficient power to run the vehicle while they are in vacuum?

        • I'm sure they've thought of this. The engine is rated at 140W and presumably is tested for the conditions it will endure especially vacuum operation. Then again they did have errors in the burn calculations of that one probe that was destroyed in the Martian atmosphere. Trivialities like forgetting to convert standard to metric...

        • Re: (Score:2)

          by sznupi ( 719324 )

          OTOH it seems they are targeting this stirling generator first and foremost for Titan mission; perhaps generally for bodies with significant atmosphere, where it works much better? And you don't need much power while in transit.

    • The heatsink might be smaller but being immersed in liquid methane, or in a thick very cold atmosphere, ought to make it work like gangbusters - much better than in air on Earth at 70 deg. The real issue will be keeping it from freezing but the delta-T should be incredible.

                Brett

  • Damn idiots! What do they expect?
    'Landing' a probe on a sea of liquid hydrocarbons....
    I hope it's got floaties on it.

  • I'm glad they admitted their motivations (Score:3, Insightful)

    by RepelHistory ( 1082491 ) on Saturday December 19, 2009 @07:01PM (#30501260)

    '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,'

    Sometimes the point of science need be be nothing more than to capture our imaginations and/or blow our minds.

    • They can't tell you the REAL reason. I mean the tax payers would bit a bit ticked off, and feel like we'd been "had" if the $400M price tag was just to deliver a chronosynclastic infundibulum!

  • This is exactly what we should be doing (Score:3, Interesting)

    by DesScorp ( 410532 ) on Saturday December 19, 2009 @07:24PM (#30501366) Journal

    This idea is beyond awesome. Sending a "ship" to sail the seas of another world. And the price... $400 million... is uber-cheap in the world of space exploration.

    Unless we can send a man to a near-Earth asteroid, this is the kind of exploration NASA should be doing... not manned attempts at Mars. Not yet.

    • Re: (Score:3, Interesting)

      by QuoteMstr ( 55051 )

      Not yet.

      What exactly are your prerequisites for a manned mission then?

      • Re:This is exactly what we should be doing (Score:5, Interesting)

        by DesScorp ( 410532 ) on Saturday December 19, 2009 @07:37PM (#30501414) Journal

        Not yet.

        What exactly are your prerequisites for a manned mission then?

        My concerns here about manned exploration are twofold:

        One, unless we're going to build a real, permanent base on the moon, and actually keep men there for extended periods of time, then we shouldn't be going back to the moon right now. It'd be a waste, and nothing more than reliving old glories without breaching new frontiers. And with declining budgets, if we actually did go back to the moon, we wouldn't stay. Again, it would essentialy be doing it just to say that we still could. A waste. So the first argument is about needless waste of funds.

        Two, as far as the other oft-proposed trip... to Mars... we shouldn't do it because of cost, but mostly, because the technology just isn't there. Specifically, we're lacking a way to keep astronauts fed and healthy for the very long trip. Suspended animation is still science fiction at this point, so unless a true breakthrough in space travel speed is found, we currently have no way to send a bunch of men on a months-long journey to another planet and back, at least not in a manner that we can afford.

        The asteroid mission right now is the only place we can actually land a man involving fairly short distances, and with the virtue of it being real exploration, literally where no man has gone before.

  • Fuck the moon! Fuck mars*! THIS is the stuff! Yeah!

    To me that would be the coolest mission, since the moon landing. The only other thing I can think of, that comes close, are the satellites that are already leaving the solar system.

    (* To those with emotional deficiencies *nudge* *nudge*: Of course I don’t mean that we should completely ignore mars, or even the moon. It’s just that it’s silly to focus on a moon landing, when on the other hand, you got stuff like this! The stuff that is ever

    • I actually think a manned mission to Titan should be considered. I would suggest using fission reactors and ion drives for propulsion. Degree of difficulty might be about the same as the Apollo program in 1960 or so.

  • Europa or bust -- Titan sucks.. (Score:4, Interesting)

    by tetrahedrassface ( 675645 ) on Saturday December 19, 2009 @08:26PM (#30501582) Journal
    Not trying to flame or troll, but these missions keep coming up. Even proposed and not funded like this one to Titan, take away from where we sorely need to explore. Poor Europa languishes [wikimedia.org]! Europa quite possibly has the best odds of actually having something worth the funding of mission; namely life. While I note the Planetary Society has pushed for a Europa mission for what seems like years now, the date of even some weird overly complex multi-national mission in 2020 is suspect.. Why on Earth is a mission to Europa not fast tracked? A craft much like Cassini/Huygens with some radar to actually see under the ice could have been designed, built and launched 10 or 15 years ago. Titan has already had a lander. Cassini is in orbit around Saturn, and while neat and cool, only Enceladus might have life, but the odds of life on Enceladus seem dimmer and more remote. Despite statements that are politically motivated (read: funding) what is the fun factor of going to Titan when we have a fruit before us in Europa that desperately deserves to be explored? I don't know these answers but when you look at the frozen surface of Europa and notice the red striations that appear in cracks in the water ice it sure looks like iron or possibly sulphur, but most likely something along the lines of halobacteria just like this! [palomar.edu]

    Maybe our agencies don't want to find life yet, as some societal and religious aspects of there being life somewhere else would drive the religious folk crazy, or maybe they don't want to contaminate Europa. Whatever the reason they need to get off of their collective rear ends (asses) and do a mission there before even going back to Mars. I just get tired of the new bright and shiny and unpaid for missions, and some of the more dumb funded one that just go in circles snapping images of useless real estate, when Europa truly deserves, on all levels, a serious series of missions that bring light to what resides under the ice.

    • Europa quite possibly has the best odds of actually having something worth the funding of mission

      A mission to Europa is being planned too (see the post upstream of us about how they plan to test the Europa probe here on Earth by using an Antarctic under-the-ice lake).

      The only difference is that this one to Titan is actually easier/cheaper to do, which is why it may happen first, but eventually Europa will be seeing a probe from us as well (pending approval from 'Dave', of course).

    • Re: (Score:3, Informative)

      by Trapezium Artist ( 919330 )

      Err, that is exactly where the Europa Jupiter System Mission (EJSM) currently under study by ESA and NASA is suppose to go, as the name suggests.

      Yes, it's more expensive than TiME and will, in principle, take longer to develop, because it's bigger and more ambitious than TiME, but it's much further along in terms of studying its technical feasibility, and so (IMHO) has a better chance of happening before TiME does. Plus, NASA is not exactly swilling in cash at the moment and if EJSM is chosen for implem

  • Kill the alien life while looking for it? (Score:3, Interesting)

    by A nonymous Coward ( 7548 ) on Saturday December 19, 2009 @10:55PM (#30502066)

    The story of human exploration on Earth has been one of navigation and seafaring

    The story of human exploration on Earth has also been one of spreading disease and wiping out indigenous populations. Bacteria are known to survive the radiation and vacuum and cold of space quite nicely, thank you. I do not think this is a good way of looking for alien life.

  • Laura (Score:2)

    by tsa ( 15680 )

    Maybe our Laura [msn.com] could go there. She would be the first teenager to sail the seas of Titan, which is much cooler than being the youngest kid to sail around Earth.

  • Sure, lakes of oil are cool, but ultimately not of any use. Based on how we think life starts, there probably is no life there. Europa on the other hand? Oxygenated oceans of water. Best chance for life of anywhere we know. Can we put this to a vote or something?

    • Re: (Score:3, Interesting)

      by sznupi ( 719324 )

      Titan is interesting because, in many ways, it is probably similar to primordial Earth, frozen in time. Even with low temperatures still the most similar place to our planet in the Solar System.

Slashdot Top Deals

Children begin by loving their parents. After a time they judge them. Rarely, if ever, do they forgive them. - Oscar Wilde

Close