Panspermia, the idea that life might travel through space to seed other planets and even other star systems, is a fascinating topic for conjecture, and our understanding of the survival of various forms of life in extreme environments only adds to its appeal. But just as SETI has an active counterpart that seeks to send rather than simply receive interstellar messages, so panspermia has its own advocates for a new kind of mission: To seed the stars from Earth. A group called SOLIS (Society for Life in Space) has sprung up around the notion. Its goal:
To propagate our family of organic Life throughout the Milky Way Galaxy and beyond. We propose to seed young planetary systems in star-forming interstellar clouds. We shall design and launch directed panspermia missions carrying the microbial representatives of Life by the year 2050.
So says the SOLIS Web site and so says society coordinator Michael Mautner, who is a research professor in chemistry at Virginia Commonwealth University. Mautner has in the past worked with solar sail expert Gregory Matloff on propulsion systems that would make it possible to seed new solar systems and has written up the idea for the Journal of the British Interplanetary Society. Now he offers a new paper for the Journal of Cosmology that focuses on what he believes to be our obligation to proceed with directed panspermia, ensuring that life does not come to an end.
Panspermia as Obligation
In a short article at Physorg.com, Mautner states his premise:
“We have a moral obligation to plan for the propagation of life, and even the transfer of human life to other solar systems which can be transformed via microbial activity, thereby preparing these worlds to develop and sustain complex life. Securing that future for life can give our human existence a cosmic purpose.”
The idea is that once we have identified planets with conditions suitable for life (and protoplanetary situations where life might one day develop), we should send organisms to seed these worlds as a way of accelerating local processes of evolution. Even the arrival of such a payload onto a comet or asteroid in a distant planetary system could pave the way for its eventual transportation to a habitable planet by local panspermia, in much the same way that material from Mars has occasionally made its way to Earth.
From accretion disks and interstellar clouds to planets identified by Kepler as being in the habitable zone of their stars, the list of targets should be extensive. The propulsion challenge is less of a problem than you might think, for Mautner is in no hurry to get there. Solar sail methods might take hundreds of thousands or even millions of years to deliver their payload, but the idea is long-term survival of life. Capsules containing about 100,000 microorganisms each and weighing 0.1 micrograms would be the delivery mechanism.
Ethics Among the Stars
All of which leads us to the ethical dilemma. How do we choose our targets so as not to disturb already existing life? Mautner considers this in his paper (internal references omitted for brevity):
Can panspermia missions perturb existing extraterrestrial life? At present, there is no conclusive scientific evidence for extraterrestrial life; though admittedly not all scientists share this opinion… Every living cell needs thousands of complex components as DNA, proteins and membranes, and the probability of these components coming together to originate life may be very small even on billions of planets…
If we still detect extraterrestrial life, we can avoid these targets. In any case, we can target new solar systems where life could not have evolved yet. We may seed a few hundred new solar systems, that will secure the future of our family of gene/protein life but will leave all the other hundred billion stars in the galaxy and their possible indigenous life unperturbed.
Yes, we can target locations where life is not likely to have already evolved, but how accurate can our assessments be given the constraints of current observational technology? Moreover, even that approach leads to potential problems. Panspermia assumes movement of life’s building blocks and even life itself through space. Seed a planetary system with life and it could be millions of years before that life moved from an asteroid in the system to a planet in the habitable zone, one that in the interval had developed life forms of its own. We can never be sure we are not displacing local life.
Mautner thinks even this scenario is not a showstopper:
If there is local life there that is fundamentally different, it will not be affected; if it is gene/protein life, it may be enriched and we can induce higher evolution. The new biospheres may prepare the way for human colonization if interstellar human travel becomes possible.
Which Life Survives?
But I’m thinking that sending cyanobacteria to other star systems to consume toxins and pump out oxygen is a dangerous form of meddling because it assumes that forms of life related to our biosphere are the ones that should survive. Ian O’Neill has an amusing but pointed take on this in a recent post:
If our life takes hold of a planet where another life had the opportunity to evolve into an interstellar civilization in a couple of billions of years time, wouldn’t we be in violation of some kind of cosmic anti-monopoly regulation (or at least in violation of the Prime Directive)?
And there’s another thing to ponder: What if “life” is the universal equivalent of some kind of infection. Is life rare because the universe has a very strong immune system? Firing our genetic code far and wide could be considered to be biological pollution.
I’m all for spreading the human influence around the galaxy, but I think this can only be considered if we physically go to these alien worlds, to evaluate these places in person before we start setting up home. Blindly sending life from Earth to habitable worlds and planet-forming accretion disks seems a little reckless, especially as we have no clue about the consequences if we started impregnating unsuspecting planets.
As we await results from Kepler and more from CoRoT, we still have no realistic assessment of the number of terrestrial planets around stars in our galaxy, nor do we have spectroscopic data that can tell us whether or not such worlds bear life. Is the meaning of life wrapped up in self-propagation, as Mautner’s paper suggests? If so, then pushing life from our biosphere outward is simply fulfilling our basic purpose.
But perhaps there is more to life, including the ethical responsibility to let life take its own directions in those niches where it has already taken hold. I’m not persuaded by a panbiotic ethics that doesn’t take into account the huge gaps in our knowledge about how and where life may form.
The paper is Mautner, “Seeding the Universe with Life: Securing Our Cosmological Future,” Journal of Cosmology Vol 5, (January, 2010), pp. 982-994 (available online).
Could we start seeding life off this planet very soon? How about panspermiating comets in our own inner solar system? A probe could deliver some radiation-hardy microbes, and stick around to monitor how they fare. Spreading life into other solar systems is a long term goal once we have the technology. What’s stopping us from starting with our own solar system?
If they could survive in the environment of an inner solar system comet, then microbes would be sure to evolve fast. Before long they’d become extra-terrestrial species in their own right.
Even if I share the ethical concerns, I find it a fascinating concept. I wonder: If in the next centuries we find that the subglacial oceans of Europa and/or Enceladus are unfortunately devoid of life, we could start to seed them. It would be a nice evolutionary experiment for the next couple of billions of years.
Broadcasting seeds into the galaxy? Hmm. Ok, so let’s assume we go ahead and do it. I see a couple of possibilities:
1. We eventually reason that doing so is unethical (for the reasons mentioned in the post), so our descendants race after the seed pods using their faster, more modern spacecraft and neutralize them.
2. We die off, so only those seeds are what remain. In this case, perhaps the galaxy is better off without our failed seeds.
Anticipating the possible outcomes, it seems sensible to not do this.
Kenneth
One thing that we could do within the 2050-2080 time-frame that would be perfectly ethical and also achievable is to seed some of the younger stars closest to Sol/Terra (within a 20 Light Year radius) that have not had the time to develop any form of life yet. Two ideal candidates for such missions are Epsilon Indi and Epsilon Eridani both of which appear to be young enough that at best they only have some of the earliest chemical building blocks of life just starting to emerge. Perhaps, it would be wise, prudent and ethical to focus on our own Interstellar Neighborhood first (~12-20 Light years) for detailed observation, travel planning and seeding missions before we go off half cocked to areas that may not belong to us. This will minimize any potential disruption while perhaps actually doing some good.
Hi Paul
Harsh words, but worth thinking about. However Life’s history is full of struggles with immigrants from different locales time and time again on this planet – look at the Great Faunal Interchange event when Panama formed and linked North & South America. Yet at the same time our clumsy efforts at moving fauna around have been relatively disastrous – for example, here in Australia for our small mammals, cats & foxes; for our unique terrains surprisingly water buffalo & camels. Camels disturb the deserts and have exploded in population – something like a million strong herd now – and need to be severely culled if our desert ecosystems are to survive unharmed. Feral Water buffalos slowly turned the Northern Territory wetlands into huge, turbid buffalo wallows with a terrible impact on native plants & animals. Now they’re being culled and some of the meat ends up in Europe.
So could sending our style of Life further afield in the Galaxy have worse unintended consequences? A moment’s reflection on the question reveals our ignorance of what’s out there.
There are solutions to these problems. Probably before the end of this century we will be able to create atomically-precise devices. At that point we will have the tools necessary to start designing and testing the smallest possible interstellar craft which, because of its small size, could be accelerated to 0.1c using a linear accelerator. But the minimal size will probably be determined by how many atoms it takes to decelerate the craft as flybys or crashes will not be able to leave seed in a solar system.
I’m totally speculating here but I would anticipate that the deceleration will occur with a superconducting loop of atoms powered by either radioisotopic atoms or an electrical current generated using the light of the target star. One could produce these craft in such unimaginable numbers that you could count on luck with one of the nanocraft surviving cosmic radiation and landing on an asteroid even without purposeful course correction.
Upon landing on an asteroid the nanocraft could construct an antenna and then receive instruction for the atomically-precise construction of anything including sensors to detect any life already present, craft to land on all sterile planets, paraterraforming of the planets, and all nature of biology (including humans). Obviously this would be very advanced technology but nothing that time won’t bring.
In this way humanity, not just microbial life, could spread throughout the galaxy at an appreciable fraction of the speed of light. I see no reason why we would settle for only microbial life, or settle for a very slow propagation, or insist that really slow evolution is the only way that we’d want intelligent life to develop.
I think the potential benefits hugely out weight the potential risks.
there are basically 4 possibilities.
1. life is rare because habitable planets are rare. Then blind panspermia attempts are essentially wasted ammo. But there is nothing unethical giving it at ry.
2. life is rare because the probability of abiogenesis is low. Then directed panspermia is the best thing we could ever do.
3. life is ubiquitous and the seeds arrive to a fully alive world full of organisms that had billions of years to adapt to it. Then the seeds either fail, or at most survive in some specialized niches giving rise to a peculiar breed of extremophiles because all niches for multicellular organisms would be already filled with better adapted organisms. Then, after billions of years ( or perhaps only a few thousands, intelligence arises , sees this peculiar gorup of organisms and realizes far sooner than we that there is intelligent life elsewhere in the universe seeking to spread life giving them perhaps a better start into SETI attempts than we have. So again. Nothing unethical here.
4. life is ubiquitous, but our capsules arrive in the extremely short tima before native life takes firm hold in the world. The result is, than in billions of years a civilization will perhaps arise out of our DNA and not the native. Which is not a big loss because this scenario assumes that life is ubiquitous and hence a tiny chance that we might wipe out a few germs is not a big deal ( we don’t consider it to be unethical killing mosquitoes out of fear we might be destroying a potential unique mosquito civilization a few billions of years into future ).
Even the fact that we are building a technological civilization here is most probably seriously hampering the other primates evolution into their own technological civilization, yet we don’t fell guilty because of it
Heck, even by binding the few dozens of kilograms of organic matter in your body, and occupying a few dozens of liters of space you are preventing other potential organisms from existing.
We are living organisms and living organisms spread. Even at the cost of overtaking other other organisms in the race. That is, what evolution is about, after all. So don’t feel guilty about it.
One can not dismiss the possibility that our own Earth was seeded by extraterrestrials. I’m an aeronautical engineer and not an expert in biology. However it is my understanding that there are three basic life domains, i.e.
Eukarya
Bacteria
Archaea
Eukarya are the more advanced life forms based upon a cell with a nucleus (We are under the Eukarya domain). Archaea are the Earth’s most ancient life form that are genetically distinct from Bacteria and Eukarya.
The science fiction argument is the Archaea are the indigenous life forms of the Earth. A couple billion years ago, extraterrestrials explored the Earth and observed that our biology had hit an evolutionary dead end with the Archaea. The extraterrestrials fabricated new life forms with an evolutionary potential for our world and seeded the Earth with them. These fabricated life forms are the ancestors of the Eukarya. One could spice the story up a bit with the assumption that the seed organisms contained inactive DNA sequences that permitted sudden evolutionary advance when the Earth’s environment permitted it, e.g. nervous system, camera eyes, self awareness, etc. This leads to an interesting line of speculation concerning the Search for Extraterrestrial Intelligence (SETI). Rather than scanning the heavens for a radio signal, we should be searching our own DNA for a set of designer’s initials. Who knows, maybe there are plans for an interstellar propulsion system along with a “return to sender address” encoded in our DNA?
I think it would be a loss to science. There’s every reason from our own experiences with exotic fauna and diseases to think such ‘directed panspermia’ could cause major damage to any already occurring ecology. (It may be our experience is not relevant, but our experience is really the only guide we have right now. We have no way of running experiments to test how our forms of life would actually affect unknown forms of life.)
I do like John Hunt’s idea of nanoscale probes, however. Very plausible!
It would be a loss to science if our lifeforms overwhelmed the native ones, removing an independently evolved, unique ecosphere and all the information about other ways life can form.
(Oops, got distracted by John, and didn’t finish my point.)
Completely wrong. We should be making every effort to make sure we don’t contaminate other worlds that have or could develop life. Ethically we should be taking care of our own world instead of wrecking somebody else’s. Scientifically there is much that could be learned by studying utterly alien forms of life that evolved in entirely separate environments. Seeding other worlds would destroy our chances of doing that.
Fascinating topic.
I tend to agree with Ian O’Neill and our administrator, and not only for ethical reasons.
As is probably well known by now, I am a strong advocate for the dispersal of human and other earthly life into our galaxy, which I even consider as imperative for our long-term survival.
However, the spreading of merely microbial life, hoping that it may one day in the very distant future give rise to more complex life and even intelligence, seems rather futile to me.
Almost surely, more or less earthlike planets will appear to be commonplace, many (most?) of them (potentially) habitable but not yet inhabited, the most interesting targets. Many of these might need some form of terraformation and could probably be terraformed to some degree relatively easily. Many others may already contain microbial life.
It is, however, quite well possible and not unlikely, that microbial life is and will remain very succesfull in surviving and adapting as it is: as microbial life. It is not at all a logical or inevitable outcome that microbial life will always develop into multicellular and complex life. After all, some 80 – 90 % of our earth’s own history of life was probably (almost) exclusively microbial and even now microbes are extremely succesfull and in fact still dominating the scene.
I think it is, almost religiously, deterministic thinking that microbial life will always follow a pathway to ‘higher’ complex life.
If we really want to give our earthly kind of life a headstart in the cosmos, using our intelligence and technology, we should carefully select our future (uninhabited but potentially suitable) planets, terraform them where necessary and seed them with (adapted) lifeforms of various kinds, particularly the higher lifeforms.
Indiscriminately sending out microbes, hoping that something ‘useful’ will arise from it somewhere, sometime, is to me like throwing piles of money out of a plane hoping that at least some of it will land in good hands, in stead of carefully investing it.
Gary — just briefly, not a chance. It’s very obvious that both eubacteria and eukaryotes are evolutionary cousins to archaea. And equally briefly, I’m with those who would rather not contaminate other life-bearing planets.
Seeding the Milky Way Galaxy with earth based bacteria seems a waste of money and really does not benefit the human race. Even if successful, we may not like what arises from the resulting stews.
Speaking of ethics, it would seem that temperate planets capable of supporting human life or ones that would require minor tampering to support human life would already have its own biospheres of some type.
I am for human supremancy over alien bacteria and other forms of miniscule life. I think reachable earth type planets as being rare. As such, the need for expansion for the survival of our species supercedes such niceties as respecting the possibility of alien bacteria advancing into higher forms of life.
(Note: “Completely wrong” in my previous post referred to my opinion of the main article, not any of the comments.)
I agree with Ronald. Terraforming dead worlds (and of course, building artificial habitats) is legitimate. But even here on Earth we have destroyed many ecosystems that we belatedly realized would have been better left alone, whether for ethical or scientific reasons. It would be criminal to do the same thing on an interplanetary or galactic scale.
I’m not seeing the rationale here. The idea of sending microbes out into space to continue the legacy of humanity seems to rest on a teleological view that evolution must progress towards complexity and intelligence. As for the idea of remote terraforming, that presumes we eventually get human beings to the destination system in a state which requires a sufficiently Earthlike environment for them to survive, as opposed to using advanced biotechnology and nanotechnological techniques to adapt people to the environments. Terraforming is a very large-scale, long-timescale project: it may be more feasible to re-engineer ourselves.
To all who think that we might start some terrible pandemic that way, perhaps even mass extinction. Name one example of a contagious disease caused by extremophiles. Just one. So I think it is completely safe to send some extremophiles to other worlds. At most they will fill an already vacant niche or displace at most a few native extremophile strains. If the world is already full.
To all who see spreading your own kind as a kind of sin, I dare to challenge you. Try to justify that taking a vacant world(or any other resource) by an existing organism thus preventing some future potential organism from utilizing it, is something evil. Justify that other future, potential alien organisms have more right to that resource than current, actual ours. And then try to justify in light of your previous justification, that you still have more right to live than the plant you uprooted, tore into pieces, boiled alive and devoured( you are all vegans, aren’t you?).
I would also add the Andromeda factor. In two billions years, the andromeda galaxy will crash into our galaxy, triggering a massive starburst that sterilizes large volumes of both galaxies by supernova blasts, and also eats up all free gas thus ending almost all new star production. The result will be a barren elliptical galaxy. So if some native life will take four billion years to develop, it will very likely be destroyed, and even if it survives, will face far less opportunities to meet other sentient beings. So if we spread genetically engineered seeds that can take a fast track to multicellularity, we may in fact increase the number and diversity of future alien civilizations not decreasing it.
Evolution is a competition, pure and simple. We don’t have to believe that our seed is the best to propogate it, we simply have to propogate, and if it does not survive, it was not the best.
*Shrugs* – that’s very reactionary, and not quite what I believe, but it is the attitude that comes in reaction to “We should be making every effort to make sure we don’t contaminate other worlds that have or could develop life.”
Why should I value OTHER life OVER my own?? Preserve and protect. But in primacy must be our OWN survival
And on another point “But I’m thinking that sending cyanobacteria to other star systems to consume toxins and pump out oxygen is a dangerous form of meddling because it assumes that forms of life related to our biosphere are the ones that should survive.”
Well, not? What if we need to move, and QUICKLY? A head start on a biosphere where we have at a minimum oxygen to pull from the atmosphere rather than create is a head start
I’m on the side of bionegineering in preference to terraforming, for reasons that I explain in my Making Alien articles.
T_U_T, you’re setting up straw bacteria. Jainists aside, the ethical dilemma applies to planets that already have indigenous life — which may be almost all the hospitable ones, given how quickly life arose on Earth (basically as soon as it became chemically possible).
@ Athena Andreadis
This is not a straw man. My post was meant exactly as an answer to the self-abolishing ‘jainist’ NS who wrote
IMHO it is clear, that he thinks that even potential distant future alien life should have precedence above actual present our one.
And, if we talk about endangering already existing biospheres, I don’t think ( pointing out the absolute lack of pathogenic extremophiles ) that this is biologically possible unless the alien life is so undeveloped that it is completely defenseless ( primordial replicators and little more ) or already moribund.
Gary: What athena said, but the origins of the three domains of life are far from clear. There are many competing hypotheses. There is evidence that supports Eukaryotes coming from a bacteria/archaea fusion… but that is no where near a proven hypothesis.
There are many many many different ideas about the origin of life and, unfortunately, issues such as lateral gene transfer have really muddied the water. Some researchers believe this is a complete red herring, while others think it has had a very significant role, while others are not sure what to think. Also, don’t say that eukarya are the most advanced… :)
TUT: Regarding disease, you’d have to have extremophiles interacting with humans before you can see the disease. Eventually such an unfortunate event would occur. It may take time (a lot of time), but if there is a way for one or more of them to live in a human, or at the expense of a human living, it will happen. Life goes where it can live, whether the life form causes other life forms pain is incidental. If the life form does cause pain to a second life form, and that pain results in the first life form living less well, then it is possible/likely that eventually the surviving members of the first life form will either cause less pain to the second life form (and thus improve their situation as well) or the survivors will be better adapted to dealing with the response(s) that the second life form throws at it in response to the pain….
Regarding “life”, there is an argument to be made that non biological life could exist… chemical life being perhaps the easiest example to imagine or understand. So, a lot of these “no life” worlds may actually have a reproducing “organism” or proto cell or set of molecules that work together… We just don’t know what is possible at this point in time.
-Zen Blade
Hi All
I see the resident biologists have set Gary straight before I could. There’s a new(ish) theory that Eukarya are a fusion of Archea, eubacteria and viruses – there’s some similarity between encapsulated viruses and the nucleus, for example. And our genomes are full of genes from viruses – whole viral sequences in fact – , archea & eubacteria too. We really are colonial archea/eubacteria/viral fusions. All of us multicellular Kingdoms – Plants, Fungii & Animals – owe a lot to the little ones that still make up most of the biosphere.
Personally I think natural panspermia has “contaminated” the Galaxy’s clement locales already. But it’s as unverifiable as any other viewpoint presently – different experts can’t even agree if interstellar panspermia is possible or not.
(‘Jainist’? That’s a new one. I’ll add it to atheist, Christian, fascist, communist, just to name some of what I’ve been called in various forums.)
There are probably numerous worlds that can only be utilized by an intelligent species (e.g. us), and we may be the only species capable of building artificial habitats. Either of those should provide adequate room for human expansion off the Earth. Why wreck actual or potential biospheres that will ultimately be of more interest if left alone?
To attempt to propagate our strain of carbon-based life in this manner seems absolutely viral in nature. What if our canisters of “life” only serve to wipe out existing populations of advanced life – much like the native denizens of the new world were wiped out by organisms carried by European explorers.
It also seems very futile for two reasons:
1. Does lightning strike twice in the same spot? Could we possible expect that our life-seeds could survive and flourish on another world that is not the same as ours? If even if they took hold, what chance is there that these organisms would evolve along the same lines that lead to us?
2. If in fact the elements (carbon, hydrogen, oxygen, etc.) so necessary to life as we know it are pervasive in the universe and the forces that organize these elements into life are also pervasive (heat, radiation, lightning, etc.) on other worlds (as they seem to be in our own solar system) — why bother with this monumental effort? It will happen of its own accord.
Considering we have only been searching for ETI for such a short time in our history, it seems so irrational and so impatient to think that we are alone in this galaxy or universe.
Athena said:
“It’s very obvious that both eubacteria and eukaryotes are evolutionary cousins to archaea.”
I think it’s an easy sell that Bacteria are evolutionary cousins to Archaea. However I need convincing that Eukaryotes are evolutionary cousins. Again, this is not my profession but based upon my layman’s understanding, Archaea is radically different from the Eukaryotes in the geometry of its DNA and its metabolism.
I like the idea of colonizing the galaxy…somebody has got to do it, why not us? Colonizing the galaxy means colonizing the stellar systems of the galaxy; When you get to one, you’ve got access to all the recourses that are buzzing about it (even the planets, for what they are worth, they do offer gravity and as much shielding as you’d like (it’s a matter of how deep you want to burrow your colony into the ground), enjoying an olympic sized swimming pool or taking in some theatre becomes a matter of cavern size…how big ya wanna build it, and why think small?) I would expect that not every system would be colonized due to lack of resources in that system or some kind of extream circumstance for which to avoid them (star about to go nova, radiation beyond your shield capabilities, where politicians are grown, …?)
But sending your spunk into a system, systems and anywhere you can without first knowing absolutley everything you can possibly know about that place is poor judgement! I mean it! ex: If you walk into my home and start spittin’ and spewin’ your chum all over my floors and walls do not be suprised if you are introduced to an alternate and painful form of flight…through the nearest wall–with limited guidance! And if it is still not understood, try this one; Walk into a lab (ANY lab) grab any petry dish, with stuff in it, or project component (for the non-buggie labs)…and spit in it. Please, you tell me of that experiment, I promise to listen.
ehem.
Please excuse my little rant. But INVASION is still invasion, I won’t pretend that it is something else.
The solution is simple; send probes to the intended systems we wish to colonize (get that up close look, and check out everything first). Don’t contaminate, polute, harm or destroy. Do take pictures, and Do anylize for all your technology can take! And please don’t crap in the puch bowl! Oh noes! It sounds like I’m against colonizing the moon and the Mars and whatever else we got in THIS system! You’d be wrong about me. Lets check everything out, learn some things, and go to town. It’s our system, lets own it!
It has been estimated that the Sol system Oort clowd contains about 3.5 Earth masses of stuff…hey, that’s a LOT of stuff! And it’s allready busted up for ya! Set up your colony on a nice asteroid, give it a little spin, and crush, refine, produce and build, till your blue-in-the-gills! Sol system should last us quite a while. Any other systems (you know, the ones we might want to colonize some day) may contain a similar yield of ‘stuff ‘, and we can colonize, and produce and grow, and never run out of breathing room. Once we can get to them. My point is that we don’t need no stinking gravity wells, though they do have their pirks. When we are at those systems and can get our hooks into ’em, that’s when we should chose to terraform or not, because that’s when we’ll have the technology (and the wisdom?) to chose.
Yes, such events almost surely occurred during the few hundreds of millions of years we multicellular organisms share this world with extremophiles. That there is no evidence that an animal was eaten from inside alive by extremophiles after it accidentally put its paw inside a geyser and touched microbial mat, is for me enough evidence that such event is extremely unlikely, and extremophiles have almost zero pandemic potential even on completely alien worlds.
I believe, that populating other planets is a bit too long distance for now. Maybe we should start with our own solar system for a start and see what comes out of it. Secondly we’re not even able to detect earth size planets for now. When we’ll be able to detect suitable planets, that could sustain life, we’ll, most probably, be able to tell if there is life on them as well.
I do not believe in the idea of just sending bacteria or other micro organisms blindly into space, hoping they’ll find their way to a suitable environment and evolve. If we truly want to ensure the future of the earths biosphere and humans we should be concentrating on finding the means to populate other planets by ourselves, not just some genetic material, that could or could not evolve.
First of all I want to emphasize that I see planetary engineering (terraforming) and bioengineering as complementary, not contradictory. Certain potentially suitable (but still uninhabited) planets may require a certain amount of modification, particularly with regard to atmosphere and temperature, because as they are they will be very unsuitable for any (complex) carbon-based life. In such a case just bioengineering might be insufficient or unnecessarily cumbersome (we are dealing with a host of different organisms, not just one species).
T_U_T, with regard to the Andromeda factor: first of all I am not at all convinced about the doom and gloom of this event (or rather a process). It will not be a clash/crash/starburst of any kind but rather a very gradual merger of two galaxies, as has happened many times before (be it in our MW’s case mainly with dwarf galaxies), resulting in one even larger galaxy. An elliptical? I am not so sure about that either, and definitely not barren. Where did you get that information?
Secondly, I sense a contradiction here: if indeed there is a certain amount of urgency involved, then this would plead for the well-targeted dissemination of more advanced life, instead of just microbes.
In general: as I mentioned before, microbes can do perfectly well as microbes and keep doing so for billions of years, without even having a need to evolve into anything else.
The greatest barriers/leaps in the history of life were probably: the biogenesis, the rise of Eukaryota, multi-celled life, complex life (with specialized organs).
The more headstart we can give our interstellar colonists, the better.
T_U_T, an obvious example of an interaction with extremophiles is botulinus toxin. Clostridium botulinum is an ancient obligatory anaerobe. It’s among the most potent potential bioweapons: 100 nanograms will paralyze you and kill you (by stopping your heart muscle) in a matter of less than a minute.
Gary, I respect people when they hold forth on things they know and heed incontrovertible evidence. I gave (granted, briefly) my professional view not of theories, but of well-established facts that I know intimately. If you are seriously proposing that eukaryotes emerged from a different lifeforming event than archaebacteria and eubacteria, I fear I will no longer be able to take you seriously.
Biology 101 texts explain this issue thoroughly. Metabolism is a red herring: the metabolism of humans is radically different from that of mice, but no one (except for new earth creationists and fundamentalists of similar ilk) seriously proposes that humans were made independently by gods or god-like aliens. The archaean DNA is identical in composition and structure to that of all other terrestrial life. If it occasionally and very locally goes into the so-called Z configuration because of context, so does human DNA, also depending on temporal and spatial context (replication, etc).
So if you “need convincing”, by all means get an introductory biology textbook and become familiar with introductory facts. Alternatively, I can give you an individual tutorial subject to my hourly consultant fees.
Gary,
it’s been a while since I have looked at all the details regarding the similarities/differences between the three domains… but as I recall the metabolism within cells is much more similar between archaea/euks than between euks/bacteria.
I just looked for a summary and found a VERY brief overview.
point number 4 is the one of interest: http://spot.colorado.edu/~schmidts/Teaching/EPOB3400/micro8-2000.html
That being said, there are other parts of eukarya that more closely resemble bacteria…
Anyways, there is plenty to debate…
Regarding viruses, I think there are two/three (maybe many more) thoughts on how the nucleus developed. Some people link the nucleus to splicing. Essentially, once you have the presence of introns, you can not have transcription and translation occurring at the same time, you really need to separate the two processes.
I believe I recall some people hypothesizing that the nucleus developed as a defense against viruses, to reduce the ability of viruses to invade the genome.
The third is that the nucleus could be a result of two cells fusing/merging and then evolving such that the genomic material is segregated from much of the rest of the cell.
Hopefully I have not completely made any of that up. Coming from a RNA processing/splicing lab, I am partial point of view. However, I doubt any one of these three explanations is completely correct.
Imagine an alien capsule lands tomorrow somewhere and sprays all its surrounding with extremely radiation resistant but otherwise harmless alien bacteria. What do you think will happen ?
1. we scrub the entire place cursing the damn evil aliens all the way, like someone really spate on the floor in your house.
2. we start preparing our relativistic missiles to retaliate against the invaders.
3. all scientists, and the most of the mankind with them will spend several weeks celebrating , and then, ( perhaps after a few wars between different biology departments fought over who gets the samples first ) we return to business as usual, glad that there is someone else out of there.
Which one is more likely ?
Your example fails on two grounds. First. Anaerobes, even obligatory ones, are not considered extremophiles. Number two. Botulism is a type of food poisoning. Not a disease that can spread between animals
It really does not make sense to contaminate a place before we have had sufficient time to study what is already there. And that is not easy, because life may not be obvious right away. There is still a good chance that what we would call extremophiles are living on Mars, and we have not discovered them, because they are sparse and underground. As I understand (Athena might correct me) there are things living on Earth under worse conditions than those on Mars, with any reasonable definition of “good conditions”.
On the other hand, a place without life is automatically uninhabitable, as it will have no oxygen and an atmosphere heavy with carbon dioxide. Remember, oxygen is a product of life.
So let us wait with the spreading until we go there ourselves, and should we find an inhabitable place, make careful decisions on what organisms to import besides ourselves. We are not new to that, as anyone who has ever tried to smuggle a salami into New Zealand can attest to.
If there are natives, treat them with respect and avoid the mistakes of earlier conquerors, hopefully we have gained some maturity since those rather shameful events. Peaceful coexistence is ethical, I think, even if it eventually destroys the alien culture. Cultures get obliterated all the time, and who are we to forbid the natives to adopt our culture, if they are so inclined.
Seeding life throughout the Universe is a wrong thought. We don’t put life there – it forms naturally and is there for a reason. We don’t own the universe, we are no god or ruler of it. The idea alone is a strong sign of narcissism. Just like when Stargate’s writers made the Asgards telling O’Neill that humans will join the great races of the galaxy. I want that too :> I’m not sure how “moderative” (as in forum moderator) SG-1 are in alien relationships so don’t take my word for granted… but I still believe SG makers are narcissist, and remember I said SG-1, not all mankind. Very large difference.
@Jonathan: apparently you have missed a large part of the ongoing discussion here on this topic. Let me briefly summarize some ideas and rationales behind the propagation of our earthly life in the cosmos and why I strongly disagree with your judgement;
– Nobody here even thinks (or at least not as expressed) that we ‘own’ the universe, even less so that we are gods.
– Propagation of our life would be for reasons of survival (risk-spreading) and bringing life to lifeless planets. I really do not see any ‘narcissism’ in it, risk maybe and utmost care for sure.
– Intelligent life is most probably very rare in the cosmos, hence simply by being what we are, we most probably already belong the ‘great races of the galaxy’. It isn’t much of a recommendation, I admit, just this lack of competition, but it is something ;-)
– We humans already work the earth, dispersed all across it, and profoundly adapted it in the process. What is the fundamental difference between this on the one hand, and terraforming/settling/seeding uninhabited planets on the other?
– I also strongly disagree with your apparent deterministic thinking (‘We don’t put life there – it forms naturally and is there for a reason’). Apart from my previous argument, why would it be any less ‘reason’ if and when *we* put it there?
What I sometimes say (teasingly) to people who reason like this is: I presume that you are also against agriculture, airplanes and automobiles? And that you never see a doctor or a dentist? After all, who are we to play gods? ;-)
Sitting on the train, thinking, a bit further to my previous post and particularly my last argument about ‘who are we to…?’;
One could carry this argument further with the same right and (ir)rationality: Who are we to deflect an incoming meteorite? Who are we to eradicate smallpox? Who are we to modify the land and grow crops? Who are we to fiddle with the forces of nature, calling it technology? Who are we, moreover, to meddle with life and death and call it medical science? Who are we, etc.? Surely we must be risking the wrath of the gods, or of nature itself.
The answer, I believe now, is more or less self-evident for anyone who thinks rationally. There is no fundamental or principle difference with venturing out of our cradle into the cosmos, only gradual ones. No doubt, every generation and culture has had its own criteria and self-imposed limits with regard to this perceived vanity and chauvinism of human nature.
One can go even further. I know that many people, here on this site and elsewhere, would argue, in stark contradiction with the ‘who are we to…’ view, that the dissemination of earthly life to other, still uninhabited worlds can be viewed not only as a bare and rationally inspired necessity for survival, but as a beautiful mission, a calling, a destiny almost verging on the spiritual. ‘To touch barren worlds with the spark of life’. Or as I once read it and was moved: in us (and maybe some others) the universe has become aware of itself.
Though personally I do not really favor such a spiritual view on this issue, I would argue that our kind must be very rare and it is no less wondrous, probably even much more so, if and when we are instrumental in disseminating life, than when lifeless ‘nature’ does it from scratch. Again, no essential difference.
I must be a terrible and chauvinistic person. Though I claim that I love nature and respect other species, I have sometimes killed cockroaches and mosquitoes, and I had my children vaccinated, sentencing countless microbes to death in doing so.
I suppose, in the end it is all a matter of priority.
I believe that there is no scope for false modesty here, rather responsibility. If we had never dared to risk the wrath of the gods, we would all still be crouching around the campfire. But thank the gods or our good fortune, that our ancestors dared to eat from the tree of knowledge. There is no way back and we do have some idea about who we are by now.
Zen Blade,
Thank you for the University of Colorado link. Very interesting. I’d like to better understand this material but it’s difficult to wade through the jargon (it’s almost another language). What mystifies me is how they can even hope to figure out when and how the different biological domains forked. As far as I can tell there is no fossil evidence and they’re inferring their conclusions by taking existing genetic information and extrapolating backwards in time. Doing so is always a very dangerous assumption.
Getting back to the main topic of panspermia by having genetic information transfer over interstellar distances: I think the only way it can be done is by transferring the information in a digital form having ECC parity checking inside a computer or long-life parity checked digital data medium. An advanced civilization is not going to biologically seed another star system by simply spraying bacteria spores at it. Long before the spores got to the other system, their genetic information would have been scrambled to simple organic molecules by galactic cosmic radiation. We already have material from other star systems in the form of carbonaceous chondrite meteors. Carbonaceous chondrite meteors do contain organic material including amino acid precursors but it’s all shredded up from cosmic radiation.
I’m going to stick to my guns and still claim that it’s possible that our own biology could have been manipulated by an advanced civilization. However I am also assuming that this civilization would be immensely old as in hundreds of millions of years old. I’m also assuming that this civilization already encompassed most of our galaxy millions (billions?) of years ago and is limited by the Laws of Physics to maximum interstellar transfer speeds of less than 5% the speed of light in automated self repairing vehicles that are of enormous size. When first encountering our world, they would have already visited thousands, perhaps millions of worlds that were very similar to ours. There would be almost nothing about our biology that they had not previously experienced. Their approach towards the modification of our biology would probably be through the genetic perturbation of indigenous life forms through the use of custom designed viruses. Their basic approach would be to accelerate the evolutionary process to the next step towards sentient life based upon their prior knowledge from studying similar biological systems. They would do this with the intent of revisiting our world in million year intervals, and perturbing our evolution again towards the next step. Again, running projects with million year time lines would not be daunting to this hypothetical civilization because it would already be hundreds of millions of years in age. This belief or hypothesis that our biology has been perturbed is testable. What needs to be discovered are large single block mutations that yielded significant capability in very old life forms. If the DNA/RNA coding behind this single step mutation looks artificial (or has a designer’s signature) then you’ll have a smoking gun.
I agree with Gary about the need for a better medium than DNA – cosmic rays are brutal in Interstellar space. I am less convinced by ETIs fiddling with DNA to improve life here. Unless life boot-strapped from chemistry then it’d never get started without a wave of a cosmic magic wand – and I don’t believe God is so unsubtle.
Speaking of the ethics of settlement and modification of alien worlds, I think that Michael McGhee (February 13, 2010 at 1:16) mentioned something quite relevant as an issue:
“Speaking of ethics, it would seem that temperate planets capable of supporting human life or ones that would require minor tampering to support human life would already have its own biospheres of some type.”
“I am for human supremancy over alien bacteria and other forms of miniscule life. I think reachable earth type planets as being rare. As such, the need for expansion for the survival of our species supercedes such niceties as respecting the possibility of alien bacteria advancing into higher forms of life.”
That raises an important ethical and practical issue: it is indeed likely, from a biological (evolutionary) point of view that:
1) Many if not most planets that are (potentially) suitable for our kind of life, maybe with some form of planetary- and/or bio-engineering, will already possess their own lifeforms, since life arose so quickly on earth as well.
2) It is likely that many if not most of those planets will only possess microbial life. Also on earth, from at least 3.8 gy to about 0.6 – 0.8 gy there was (almost?) exclusively single-celled life, i.e. is for some 80% of the ‘inhabited’ lifespan of our planet.
What if it appears, in some future, that the only earthlike planet within tens of light-years that is habitable/terraformable has an indigenous biosphere consisting of microbes? E.g. suppose that Alph Cen B indeed has an earthlike planet with a primordial earthlike atmosphere and lots of water, all very nice, but also microbial life. And this planet is the only one even remotely suitable within tens of ly. What then? I don’t expect that, if and once we humans are able to get there, we’ll refrain from settling it.
I tend to agree with Michael McGhee on this.
In my humble opinion, the idea of “seeding” potentially habitable extrasolar planets is a bad idea. The cost, benefit and reasoning behind the whole thing, just do not add up. Here are a few reasons why I think so:
1. the samples sent may not “take” to their new location and so the cost and time of sending them there are wasted.
2. the samples may “take” but fail to do so in the predicted way, hence also a waste of time and money.
3 the ability of a few tonnes of bio-chemical material (probably the limit of what can be sent) to influence the evolution of a whole star system is probably negligible and to hope for anything better is ridiculous. Heck, sending the mass on the whole earth in biological and chemical specimens will most probably not influence the evolution of a particular star system to any great amount.
..4. the time scale involved is just too long. What if in the 50,000 or 100,000 years for the seeds to get there, other life forms have travelled there and are busy settling in and all of a sudden, what basically amounts to a bio-chemical attack, takes place and wipes them out or ruins their own plans?
5. the reason for propagating our form of life over others, even potential life forms, is questionable. It may be too “jainest” for some but to me, forcing our way of being/doing things, at the expense of others, smacks of fascism. Bringing morality (the article say it is our moral obligation to propagate – or words to that effect) into the argument is usually a ploy used by politicians use to justify or direct attention from a stance that is basically unjustifiable.
Given enough time (100,000 years or so) we should go out to suitable destinations and explore with a code of ethics, dare I say it, similar to those of the prime directive from star trek. If we are not up to surviving for the next 100,000 years then that’s that and it is ok – hopefully we at least will have tried. Life on earth will still go on. Indeed, by the reasoning of the above article we will have already contaminated our locale enough to leave our stain.
3. life is ubiquitous and the seeds arrive to a fully alive world full of organisms that had billions of years to adapt to it. Then the seeds either fail, or at most survive in some specialized niches giving rise to a peculiar breed of extremophiles because all niches for multicellular organisms would be already filled with better adapted organisms
Sorry, my previous post was posted accidentally and prematurely. Since most of what I wrote somehow disappeared in the process, I’m not sure its worth redoing. The topic has been pretty thoroughly covered already.
(This post may contain sarcasm designed to spur thought.)
Sreptococcus mitis + Surveyor 3
I think the odds are about the same for this panspermia as described working vs random bacteria comming to life on Mars (maybe starting around one of our landers or ‘naturally’) when the sun gets a little bigger. I really hope this doesn’t cause everyone to cancel all future landers.
Nature doesn’t care, survival doesn’t either. There are no natural ethics. If panspermia as described were a problem, and there are many other possible civilizations out there, then explain the Fermi-ish paradox? They must have all come to the same no-sperm/no-communication (knowledge is viral) conclusion? How is it that we’re not getting attacked constantly by alien DNA? Maybe there is no paradox, life is hard and previous civilizations may or may not have tried panspermia with variable (complexity) success. (In this case panspermia as an activity is easily ethical.) Complex over simple with every breath, until I catch something nasty.
@Bounty, I agree, this is similar to what I meant: I do not see much risk in seeding the MW galaxy with our microbes, but also not much advantage.
If we send out life into the cosmos, it will be not only to preserve that life itself, but also to give life elsewhere a jumpstart or a headstart, helping it to take some major obstacles.
However, it is very well possible and there are indeed indications, that the initial originating (abiogenesis) of life wasn’t the biggest hurdle. Rather, the development to multi-cellular and on to complex (specialized organs) life took much longer and may not even be an inevitable outcome.
Therefore, I would advocate the dissemination of much more advanced life (and possible genetically adapted to specific conditions) than just micro-organisms.
If I want my children to succeed in life, all the way through university, it is nice that I am present at their births, but not nearly sufficient.
Regardless of how many worlds we’ve detected by 2050, it would be nothing short of ludicrous to even contenplate sending microbes to them without sending probes first & checking if it has any life on it already. Heck, we have no idea whatsoever what kind of life exists (if any) in our own solar system, never mind taking the rest of the galaxy into consideration as well.
Not even taking any potential problems/issues into consideration with such a mission but the biggest drawback for me is the time it would take for them to reach their destinations. With a timeframe ranging from 100’s of thousands of years to millions. With the way technology is advancing, we will probably be able to set foot on these planets ourselves within the next 500/1000 years (maybe even far sooner).
Furthermore, if they have such funds available, then they would be far better served utilising it in other ways. Ways that will directly benefit mankind in the short-term.
This planet has finite resources. The population of some nations are growing at an exponential rate. Clean drinking water is going to be at a premium in 20/30 years. So if they want to help, then they could help setting up a human colony on Mars. Sending probes to our nearest few stars to check for any habitable planets etc, etc.
Let nature take care of ‘panspermia’ missions with comets & human beings worry about saving their own long-term future of themselves first! If the galaxy is devoid of life & we’re alone, then since it’s been waiting all these billions of years, I don’t think another few hundred/thousand years for us to take care of ourselves first will cause too much harm.
When we’re in the Star-Trek age flying around in our big ships. Not only will be be able to seed life, but we’ll be able to create/place far more complex/advanced forms of life on planets, than if we were to simply send microbes right now.
So a note to Mr Mautner: For the time being, please worry about events closer to home & take a more short-term approach to any future projects you may undertake!