# Cassini: Chance for life on Titan? **URL:** \ **Category:** Great Debates\ **Created:** [July 1, 2004, 6:00am UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019 "2004-07-01T06:00:57Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Aeschines](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aeschines/32/16251_2.png) [@Aeschines](https://boards.straightdope.com/u/Aeschines)\ **Post date:** [July 1, 2004, 6:00am UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/1 "2004-07-01T06:00:57Z")
Here is the latest yahoo story on the mission: [http://story.news.yahoo.com/news?tmpl=story&cid=570&ncid=753&e=1&u=/nm/20040701/sc\_nm/space\_saturn\_dc](http://story.news.yahoo.com/news?tmpl=story&cid=570&ncid=753&e=1&u=/nm/20040701/sc_nm/space_saturn_dc) The Huygens probe will break away and study the atmosphere of Titan. It could tell us more about whether there is a chance for life on this moon, which is as large as a small planet. Titan is considered one of the few possible candidates for bearing life in our solar system. It has a solid surface, a substantial atmosphere, and lots of good chemicals like methane and ethane. It might be able to support simple life forms like protazoa. Of course, chances of Titan bearing life are generally considered remote, but what is your assessment? My guess is that it is about 1 in a million. ---
**Author:** ![BytopianDream](https://avatars.discourse-cdn.com/v4/letter/b/9de0a6/32.png) [@BytopianDream](https://boards.straightdope.com/u/BytopianDream)\ **Post date:** [July 1, 2004, 10:45am UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/2 "2004-07-01T10:45:16Z")
I’m really hoping the chances of life are 1:1. Doubtful, but it would be damn interesting. I think we will learn a whole lot of interesting stuff regardless. I can’t wait to read all the fun stuff they find. Going down to Titan gonna have myself a time! Friendly microbes everywhere, humble cells without temptation! Whee!!! The real question I guess would be: Can life survive such a cold environment and lack of free oxygen? Perhaps life could _survive_ but not really live and evolve. Are there anarobic thermophobic microbes on Earth? ---
**Author:** ![Aeschines](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aeschines/32/16251_2.png) [@Aeschines](https://boards.straightdope.com/u/Aeschines)\ **Post date:** [July 1, 2004, 10:50am UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/3 "2004-07-01T10:50:33Z")
> [@BytopianDream](#): > > The real question I guess would be: Can life survive such a cold environment and lack of free oxygen? Perhaps life could _survive_ but not really live and evolve. Are there anarobic thermophobic microbes on Earth? My guess is: yes, it can. I don’t think we’ll find puppies and kittens swimming through the methane slush, but there could be anaerobic microbes there. The big question being whether they could live without a lot of water. ---
**Author:** ![spectrum](https://avatars.discourse-cdn.com/v4/letter/s/9fc29f/32.png) [@spectrum](https://boards.straightdope.com/u/spectrum)\ **Post date:** [July 1, 2004, 3:38pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/4 "2004-07-01T15:38:17Z")
Life is durable. It can handle hot and cold environments, inhospitable environments, far better than one would think. We find life everywhere on earth, even places where by all rights it just shouldn’t thrive. If the conditions on Titan were ever capable of producing life, chances are that it’s still there, somewhere. Unless it needs water. Most life on earth needs water (or water ice). Without water, or if there was water and now there’s not, then the moon may be devoid of life. Though it probably won’t be for long. There’s a very non-zero chance that earth microbes hitched a ride on Cassini-Huygens, and that the probe will bringing some earth germs to Titan. Whether they survive or not would be an interesting question, too. Same for the microbes that were certainly on the two Mars rovers. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [July 1, 2004, 5:05pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/5 "2004-07-01T17:05:12Z")
Well they know that there is water vapor. And suspect that there is water ice. And organic compounds of variuos sorts. Unclear if it has had liquid water at points or not. It currently has an “anti-greenhouse effect” going on, in which its atmosphere reflects enough energy out that it cool it down further. But this does not rule out that a green house effect was extant in its past. Or that geothermic activity could have raised surface temps in the past either. And if it did exist, then it is indeed possible that it could adapt to conditions including the lack of liquid water or suriving as airborne organisms in the vapor. Who knows? [This old BBC report](http://is1.websearch.com/_1_2P2GUYR042U6BW7__websrch.barweb.50099/search/inc/results/web/framed.htm?display-url=http%3A%2F%2Fwww.resa.net%2Fnasa%2Ftitan.htm&qkw=titan%20water%20life&nextid=di5:1088700569235&frame=http%3A%2F%2Fclickit.go2net.com%2Fsearch%3Fpos%3D1%26ppos%3D0%26plnks%3D0%26uplnks%3D20%26cat%3Dweb%26cid%3D239170%26site%3Dsrch%26area%3Dsrch.noncomm.inktomi%26shape%3Dtextlink%26cp%3Dwebsrch.barweb.50099%26cluster-click%3D0%26pd%3D0%26coll%3D0%26query%3Dtitan%2Bwater%2Blife%26rawto%3Dhttp%3A%2F%2Fwww.resa.net%2Fnasa%2Ftitan.htm) shows why they want to look. > [@](#): > > A team from the Infra-red Space Observatory (Iso) studying Titan found the moon has a thick atmosphere of orange clouds. > These clouds contain organic chemicals similar to compounds which gave rise to life on Earth four billion years ago. > Athena Coustenis, a Paris-based astronomer in the Iso team, said: "Water vapour makes Titan much richer. We knew there was carbon monoxide and carbon dioxide in Titan’s atmosphere, so we expected water vapour too. > “Now that we believe we have found it, we can expect to better understand the organic chemistry taking place on Titan and also the sources of oxygen in the Saturnian system.” > Dr Paul Murdin, of the British National Space Centre, said: “Perhaps everywhere we go, if it is not too hot and not too cold, we will find some sort of biology of simple life, or perhaps advanced life like ourselves.” ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [July 1, 2004, 5:18pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/6 "2004-07-01T17:18:09Z")
> [@](#): > > Dr Paul Murdin, of the British National Space Centre, said: “Perhaps everywhere we go, if it is not too hot and not too cold, we will find some sort of biology of simple life, or perhaps advanced life like ourselves.” The [surface temperature of Titan](http://saturn.jpl.nasa.gov/news/features/saturn-story/moons.cfm) is around -178°C (-289°F). You’ll be needing a good stable heat source if you want to keep water based lifeforms alive out there. ---
**Author:** ![BrainGlutton](https://avatars.discourse-cdn.com/v4/letter/b/82dd89/32.png) [@BrainGlutton](https://boards.straightdope.com/u/BrainGlutton)\ **Post date:** [July 1, 2004, 8:06pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/7 "2004-07-01T20:06:32Z")
> [@spectrum](#): > > Life is durable. It can handle hot and cold environments, inhospitable environments, far better than one would think. We find life everywhere on earth, even places where by all rights it just shouldn’t thrive. Not quite everywhere. For instance, there is practically no life in Antarctica. Life can thrive in the supercooled waters of the Arctic Ocean, but not on the mile-thick ice shield that covers most of Antarctica. There are some birds living on the Antarctic coasts – they live entirely on fish, and they can never venture very far from the water. Inland – nothing. There is air, there is sunlight, and there is (in solid form) water, but apparently these are not enough to support life. With all its diversity and ingenuity and astonishing adaptability, Earth’s biosphere has never produced a plant that can grow on water ice. No plants means no herbivorous animals, which means no carnivorous animals. I would not be surprised – though I do not know this for a fact – if the air over most of the continent is entirely devoid of airborne bacteria. The point: To our knowledge, there are some environments where life simply cannot exist. When I think about the possibility of life on Mars in the distant past, I am always brought up short by considering that Mars probably has never been much warmer than it is now. Antarctic temperatures, practically no water or air – what are the chances for life? So is Titan, so much, much further out from the sun, really a likelier prospect? Even for supporting a biosphere of microbes? What is the average temperature on Titan, anyway? ---
**Author:** ![BrainGlutton](https://avatars.discourse-cdn.com/v4/letter/b/82dd89/32.png) [@BrainGlutton](https://boards.straightdope.com/u/BrainGlutton)\ **Post date:** [July 1, 2004, 8:14pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/8 "2004-07-01T20:14:45Z")
> [@spectrum](#): > > Though it probably won’t be for long. There’s a very non-zero chance that earth microbes hitched a ride on Cassini-Huygens, and that the probe will bringing some earth germs to Titan. Whether they survive or not would be an interesting question, too. Same for the microbes that were certainly on the two Mars rovers. 😕 Is it really possible for earth microbes to survive, clinging to a surface of cold metal in hard vacuum, with no food source, for the many months it takes a space probe to reach another planet? ---
**Author:** ![Troy\_McClure\_SF](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/troy_mcclure_sf/32/4150_2.png) [@Troy\_McClure\_SF](https://boards.straightdope.com/u/Troy_McClure_SF)\ **Post date:** [July 1, 2004, 8:21pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/9 "2004-07-01T20:21:42Z")
> [@BytopianDream](#): > > Are there anarobic thermophobic microbes on Earth? [Ayup](http://www.straightdope.com/classics/a1_092.html). > [@Cecil Adams](#): > > If the body has had the misfortune to have been sealed in an airtight metal casket, though, anaerobic bacteria–that is, those that thrive in an airless environment–will have had a chance to get to work, and the body will have putrefied, meaning it will be partially liquefied. ---
**Author:** ![Cervaise](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cervaise/32/16693_2.png) [@Cervaise](https://boards.straightdope.com/u/Cervaise)\ **Post date:** [July 1, 2004, 8:47pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/10 "2004-07-01T20:47:01Z")
> [@BrainGlutton](#): > > Is it really possible for earth microbes to survive, clinging to a surface of cold metal in hard vacuum, with no food source, for the many months it takes a space probe to reach another planet? One of the Apollo lunar missions (Apollo 12, IIRC) went to the site of an unmanned lander that had been previously sent to the moon, some years before. They found Earth bacteria on the lander: not exactly thriving, but enough “alive” (as much as that means anything in microbiology) that the bacteria could be successfully cultured. They’d been in hard vacuum and hard radiation, and suffering a two-weeks-in-sunlight, two-weeks-in-darkness cycle, for years, and they were essentially fine. Don’t underestimate our microscopic cousins. If they had cell phones, they’d take over the world. 🙂 Re the OP, I think the chances of finding life on Titan are remote, though I won’t try to put an exact number on it. However, they’re nonzero. That’s why we have to go look. And the more you know about astronomical exploration, the more you recognize how rarely we’re perfectly right when we make predictions and then go look to see what’s there. Initially, we thought our own solar system was typical. But the more we look at other stars, the rarer our arrangement seems to be. Similarly, when we went to Jupiter, we didn’t know what the Red Spot was, and we figured the moons would be cold balls of rock; it was truly shocking to find out that many of Jupiter’s moons are themselves much more interesting than the planet they orbit. And so on, and so forth. That’s why we do science: to see whether the world actually behaves according to our beliefs (and to see whether, as responsible science-minded people, we can change our beliefs when the evidence doesn’t add up as expected). In light of that, the only responsible position toward the Cassini-Huygens mission is that no matter what the result is, it’s going to be very interesting. Life? Very interesting. No life? Very interesting, for other reasons. (Compare the chemical reactions in the Martian soil during the Viking mission.) Methane seas? Very interesting. Bare rock like Venus? Very interesting. Me, I can’t wait. I have no solid expectations, and I’m _still_ predicting big surprises. ---
**Author:** ![Cervaise](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cervaise/32/16693_2.png) [@Cervaise](https://boards.straightdope.com/u/Cervaise)\ **Post date:** [July 1, 2004, 8:52pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/11 "2004-07-01T20:52:50Z")
Found a [cite](http://science.nasa.gov/newhome/headlines/ast01sep98_1.htm) for the bacteria-on-the-lander story. It was Apollo 12, the unmanned probe was Surveyor 3, and it had been on the moon two and a half years when the astronauts landed at the site. > [@](#): > > “I always thought the most significant thing that we ever found on the whole goddamn Moon was that little bacteria who came back and lived and nobody ever said shit about it.” > —_Pete Conrad, Apollo 12 commander_ ---
**Author:** ![Kluge](https://avatars.discourse-cdn.com/v4/letter/k/a183cd/32.png) [@Kluge](https://boards.straightdope.com/u/Kluge)\ **Post date:** [July 1, 2004, 9:03pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/12 "2004-07-01T21:03:22Z")
> [@Cervaise](#): > > Don’t underestimate our microscopic cousins. If they had cell phones, they’d take over the world. Yes, but I was under the impression that NASA heavily sterilizes their probes in cases such as these. I think it may, however, just be a lower bacteria count allowance, though I’m not sure… Anyone know if this is true or not? ---
**Author:** ![MEBuckner](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mebuckner/32/2896_2.png) [@MEBuckner](https://boards.straightdope.com/u/MEBuckner)\ **Post date:** [July 1, 2004, 9:19pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/13 "2004-07-01T21:19:57Z")
The Huygens probe is not considered to pose a risk of bio-contamination (or at least it wasn’t when it was launched): [Frequently Asked Questions - Huygens Probe](http://saturn.jpl.nasa.gov/faq/huygens.cfm): > [@](#): > > **What precautions have been taken to prevent the Huygens Probe from contaminating Titan when it lands there?** > > The Committee on Space Research (COSPAR), an interdisciplinary committee of the International Council for Science, maintains a consensus international planetary protection policy to be followed by spacefaring nations. In 1988, the U.S. National Research Council’s Space Studies Board, working under COSPAR guidelines, determined that the Cassini-Huygens mission fit into “Category II” as follows: > > “Category II missions comprise all types of missions to those target bodies where there is significant interest relative to the process of chemical evolution and the origin of life, but where there is only a remote chance that contamination carried by a spacecraft could jeopardize future exploration. The requirements are for simple documentation only. Preparation of a short planetary protection plan is required for these flight projects primarily to outline intended or potential impact targets, brief pre? and post-launch analyses detailing impact strategies, and a post-encounter and End-of-Mission Report which will provide the location of impact if such an event occurs. Solar system bodies considered to be classified as Category II are listed in the Appendix to this document.” For original documents, see [http://www.cosparhq.org/scistr/PPPPolicy.htm](http://www.cosparhq.org/scistr/PPPPolicy.htm). > > As a Category II mission, the Huygens Probe was not sterilized. For more information on this, see this European Space Agency web page on planetary protection: [http://www.esa.int/export/esaCP/ESAUB676K3D\_Life\_2.html](http://www.esa.int/export/esaCP/ESAUB676K3D_Life_2.html) > > For information on NASA’s planetary protection policies and procedures, see [http://planetaryprotection.nasa.gov/pp/index.htm](http://planetaryprotection.nasa.gov/pp/index.htm). That ESA page linked to in the above quote says: > [@](#): > > When Cassini-Huygens was launched in 1997, scientists thought that life was simply too unlikely to exist on the cold Titan. They therefore labelled the project low risk, with no sterilisation procedures considered necessary. However, according to COSPAR rules, the spacecraft was assembled in a clean room, that is, with less than 100 000 particles per unit of volume. ---
**Author:** ![BytopianDream](https://avatars.discourse-cdn.com/v4/letter/b/9de0a6/32.png) [@BytopianDream](https://boards.straightdope.com/u/BytopianDream)\ **Post date:** [July 1, 2004, 10:29pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/14 "2004-07-01T22:29:04Z")
> [@Troy McClure SF](#): > > [Ayup](http://www.straightdope.com/classics/a1_092.html). I think the key thing I was asking (which I miss-typed) was **thermophilic** anaerobic (which I mispelled) bacteria. I know of the regular guys, but what about the super cold on Titan? Can life sustain there? I have higher hopes of life in Jupiter and Saturn’s atmosphere than I do on Titan. But I still have hope. I am certainly not a chemist or biologist, but in a class I took on _Life on Other Worlds_ the biology professor who taught part of the class was pretty much convinced that water was 99.99% (as he put it) necessary for life, and in liquid form to boot. And if life did start up there in a warmer time, did it have enough evolution time to adapt to the change in temperatures? I hope so. Even if we find some spores that have been sitting around for millions of years, I would like to find even that. But with the probe’s limited lifespan, I doubt it. ---
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [July 1, 2004, 10:53pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/15 "2004-07-01T22:53:17Z")
I _seriously_ doubt that we’re going to find any life on Titan, whatsoever. It is a cold and inhospitable place, so live as we know it, certainly _couldn’t_ exist. Life as we _don’t_ know it, might exist, but I seriously doubt that the Huygens Probe has the necessary gear to detect it. I’d be happier than hell if we found it, but I’ll lay money that we don’t. ---
**Author:** ![Aeschines](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aeschines/32/16251_2.png) [@Aeschines](https://boards.straightdope.com/u/Aeschines)\ **Post date:** [July 2, 2004, 6:19am UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/16 "2004-07-02T06:19:44Z")
Is Hugyens going to take some bad-ass pictures of Titan’s surface? This stuff makes me really geeky. ---
**Author:** ![BytopianDream](https://avatars.discourse-cdn.com/v4/letter/b/9de0a6/32.png) [@BytopianDream](https://boards.straightdope.com/u/BytopianDream)\ **Post date:** [July 2, 2004, 11:07am UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/17 "2004-07-02T11:07:34Z")
> [@Aeschines](#): > > Is Hugyens going to take some bad-ass pictures of Titan’s surface? > > This stuff makes me really geeky. I dang well hope so, I need a new desktop. The pictures they got from Mars were great. I think not having pictures is not so good for public relations and stuff. ---
**Author:** ![Aeschines](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aeschines/32/16251_2.png) [@Aeschines](https://boards.straightdope.com/u/Aeschines)\ **Post date:** [July 2, 2004, 11:24am UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/18 "2004-07-02T11:24:45Z")
> [@BytopianDream](#): > > I dang well hope so, I need a new desktop. > The pictures they got from Mars were great. I think not having pictures is not so > good for public relations and stuff. Yah, and when the probes crash ‘n’ stuff. Major downer! :mad: ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [July 2, 2004, 6:17pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/19 "2004-07-02T18:17:38Z")
> [@BrainGlutton](#): > > Not quite everywhere. For instance, there is practically no life in Antarctica. Well, not so fast. Lookee [here](http://www.resa.net/nasa/antarctica.htm#microb-main) > [@](#): > > researchers are finding that Antarctica is not a sterile, lifeless environment. Micro-organisms have been found to exist in the upper layers of the ice sheet and micro-organism fossils have been found in deep ice cores. Colonies of bacteria are able to survive the long winters of extreme cold by a form of hibernation. In the Antarctic “summer”, the warmth of sunlight is sufficient to melt small quantities of liquid water around dust particles acting as tiny solar collectors. It is at these sites that the bacteria wake up and go through their abbreviated life-cycles. Algae have also been discovered co-existing in these colonies - whose seeds over-winter and then “sprout” in the south polar summer. > > Ice cores drilled into the ice of Antarctica exhibit the presence of microbial life at all levels. Recent electron scanning microscope studies of these micro-fossils have revealed numerous forms that are not immediately identifiable. Research is underway to determine if these represent new varieties of microbial life. Russian scientists have been able to revive and culture bacteria, yeast, fungi, and other microbes found in ice cores that carbon date to more than 200,000 years old! This is reminiscent of the bacteria that were found surviving in hibernation on the U.S. Surveyor moon lander that was retrieved by the Apollo astronauts, having outlasted the airless and hostile lunar environment for almost three years! Clearly, microbial life "goes on and on and on…"The implications of this ability of microbial life to be “long-suffering” are certainly provocative in terms of biologic viability in the extreme environments beyond Earth. I am reminded of the triops that my kids get at the toy store. These are actually acquatic crustaceans that live in desert environments. They survive as dessicated fertized eggs for dozens of years, until a rainstorm occurs and creates shortlived pools of water. In short order they hatch, breed, and lay the next generation of eggs which lay dessicated and dormant for however long it takes for liquid water to again occur. And so an acquatic species survives in the desert. Life can very creative. And that is just on Earth. ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [July 2, 2004, 6:30pm UTC](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019/20 "2004-07-02T18:30:05Z")
Well yes but note that it requires liquid water at some point and temperatures that never get less than -50C. Titan, though, is a haze shrouded moon with surface temperatures that average -178C. Now seeing how tidal forces can drive heating (i.e. Europa) it may not be wildly impossible for “warm” areas of Titan to exist, but I doubt we’re going to see swaying “vegetation” at the landing site. Though I’d like to be wrong. 🙂 [Next page](https://boards.straightdope.com/t/cassini-chance-for-life-on-titan/253019.md?page=2)