ADVERTISEMENT
  About the SA Blog Network













Observations

Observations


Opinion, arguments & analyses from the editors of Scientific American
Observations HomeAboutContact

Twin Earth May Be Better Than Earth for Life

The views expressed are those of the author and are not necessarily those of Scientific American.


Email   PrintPrint



Artist's vision of Kepler-186f

Pseudo-Earths are out there. That’s the message of today’s exciting announcement that a planet about the same size as Earth lives in its star’s habitable zone—the temperate region around a star where liquid water might flow. “For me, the impact is to prove that such planets really do exist,” said David Charbonneau, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, to Nature.

It’s an article of faith that the planets most likely to harbor life are the planets most like Earth. Our home is, after all, the only known place in the universe that gives life shelter. From our sample of size of one we peer out into the cosmos for places that might mirror back the essential features that make our planet so fertile.

Unfortunately, discovering distant planets is so difficult that we can only discern the barest information about any potential neighbor. In the case of Kepler-186f, the newly discovered Earth-like exoplanet, astronomers know its size (about 1.11 times the radius of Earth), the length of its year (130 Earth days), and how much solar radiation it receives (about 32 percent of what the Earth gets from the Sun). Other questions—what is it made of? does it have an atmosphere? how hot is its surface?—we can only answer indirectly, if at all. There’s no way to tell, in other words, if the surface of Kepler-186f supports swimmable temperatures between zero and 100 degrees Celsius.

But we can flip the question of habitability around. Instead of assuming that the most life-friendly planets are Earth-sized orbs circling a Sun-like star, we can ask what characteristics a planet might have if we were to build it from scratch with the express purpose of setting the stage for the genesis of life and evolutionary success. What simple beginnings would best brew life’s endless forms most beautiful?

The answer, it turns out, isn’t an exact copy of Earth. Astronomers have recently begun to ponder the possibility of a “superhabitable” planet—one that has all the life-giving features of Earth, but more so. What are the characteristic signatures of such a world?  As the astronomers René Heller and John Armstrong describe in a recent paper, these planets will be slightly larger than Earth—up to about two or three times Earth’s radius. These chubby Earths would presumably have more magnetic shielding from solar radiation; greater tectonic activity, which means more volcanoes to belch carbon dioxide into the atmosphere; a thicker atmosphere, held in by the greater surface gravity, and simply more surface area for life to roam.

A moon wouldn’t hurt either. As Lee Billings described in our January story “The Search for Life on Faraway Moons,” a moon surrounding a distant planet could create a tidal heating effect—the orbit of the moon stretching and contracting the planet enough to generate frictional heating forces that would make a planet habitable even if it orbited outside of its star’s habitable zone. Discovering a moon is much trickier than finding a planet itself, however. (A few intrepid astronomers are on the case.) For now, the only special planetary attributes we can reliably search for are those that a spacecraft like Kepler can discern: size and distance from star. And, of course, what the star itself looks like.

In this, the planet Kepler-186f may be a winner. The star it orbits—Kepler 186—is a dwarf star, dimmer and smaller than our Sun. These stars burn a little less vigorously than our Sun does, which means their nuclear fuel can last for billions of years longer—additional billions of years for evolution to do its work.

With a radius 11 percent larger than Earth’s and an orbit around an extremely long-lived dwarf star, Kepler 186f may be undersold as a twin of Earth. It could be our first example of a superhabitable world.

Image courtesy NASA Ames/SETI Institute/JPL-Caltech


About the Author: Michael Moyer is the editor in charge of space and physics coverage at Scientific American. Follow on Twitter @mmoyr.

The views expressed are those of the author and are not necessarily those of Scientific American.





Rights & Permissions

Comments 45 Comments

Add Comment
  1. 1. logistics101 9:31 am 04/18/2014

    no life will ever be found out there because there is none out there. it’s a terrible waste of money and time to be searching for it on other planets. time will prove me right on this.

    Link to this
  2. 2. jtdwyer 10:09 am 04/18/2014

    logistics101 – well put!

    Link to this
  3. 3. jtdwyer 10:13 am 04/18/2014

    Kepler-186f probably is more habitable than Earth – at least it will be by the time we get done with Earth! <%)

    Link to this
  4. 4. tuned 10:46 am 04/18/2014

    Cure cancer and stuff 1st.

    Link to this
  5. 5. Lizette 10:47 am 04/18/2014

    [Student number: 04515596] (According to studies) At the rate we’re going now, by the year 2050 all of Earth’s rescources will be exhausted and the population will have grown so much that there will be no room left.
    Kepler-186f may just be some future generation’s only hope…

    Link to this
  6. 6. KMacLaine 1:16 pm 04/18/2014

    @ logistics101, jtdwyer

    It constantly amazes me how people read an article like this and comment how they are SURE, without any kind of doubt that they KNOW there (is or isn’t) life on other worlds.

    Either you have visited and extensively studied every single other planet in the universe – in which case let me congratulate you on being exceptionally well-travelled;

    OR

    You are doing like so many people do today and asserting your own opinion as fact.

    I haven’t heard anything about anyone discovering life on other planets, nor about anyone extensively and conclusively studying every single other planet in the universe to rule out the possibility of life.

    We don’t know if there is or isn’t life on other planets, let alone intelligent life, but the odds do seem to be in favor of the existence.

    Link to this
  7. 7. skiddlybop 2:00 pm 04/18/2014

    I agree with KMacLaine except for “the odds do seem to be in favor of the existence” if the calculation shown at http://www.godandscience.org/apologetics/probabilitieslife.html is correct.

    Link to this
  8. 8. hungry doggy 2:28 pm 04/18/2014

    Why all the fuss? As I recall there are something in the neighborhood of 200 billion stars in our Milky Way galaxy. The number of planets in our galaxy capable of supporting life must number in the millions. Kepler 186f is interesting. But it looks like NASA is hyping it to the ignorant as a fund raising hook.

    Link to this
  9. 9. Jomerod137 3:27 pm 04/18/2014

    News as these will appear sooner and more often. Life is immanent to Universe and boils to its full extent.

    Link to this
  10. 10. lavaroy 3:48 pm 04/18/2014

    Jomerod and jt: You have taken opposite sides of the likely vs. unlikely debate. Jt, your position is that life is so unlikely it’s incredible that it happened at all, yet here we are. So many perfect accidents had to happen for us to appear and evolve. Jomerod has the position that life is likely, that there is a process that confounds our scientific thinking, yet is ubiquitous and forces life to emerge.

    Link to this
  11. 11. Dr. Strangelove 7:29 pm 04/18/2014

    Moyer
    Venus has thicker atmosphere and more CO2 but it’s hot enough to melt lead.

    Lizette
    What resources are running out? Water? Desalinate seawater and it’s physically impossible for humans to consume all that water. Food? Cultivate all the arable land in the world and you can feed 50 billion people. Energy? Nevada alone gets more solar energy than the output of all the power plants in the world. Land? If Alaska had the population density of New York City, you can put all 7 billion people in Alaska and it will still have vacant area larger than Texas and the rest of the world will be uninhabited. Maybe environmentalists are running out of imagination.

    Link to this
  12. 12. ravisamson 7:30 pm 04/18/2014

    When people assume that only planets that are similar to ours can harbor life, they are restricting themselves to life-forms very similar to those found on planet earth.

    Can anyone say for sure that sentient forms of existence totally different from us can not exist? How can you know that a star is not a thinking life-form?

    All you folk out there who believe in gods and stuff like that, you got to agree with me. For the record I do not believe in a creator god.

    Link to this
  13. 13. Edgod1 7:48 pm 04/18/2014

    Even if there is life on other planets, what are the chances of it being as intelligent as humans? More likely like dinosaurs who, if they hadn’t have been destroyed by that big rock might still dominate life on Earth. And even if they were as smart as humans, what are the chances of them having civilization? Australia’s Aborigines had a culture that stayed stagnant for , years before the English came and disturbed their equilibrium. The hot-houses of civilization in Europe were helped on their path by taming creatures such as horses, whereas the civilizations of the Indians in the Americas hadn’t even invented the wheel. So we have to face the possibility that we may be the only technocratic people in the universe, whose destiny it is to civilize all the rest.

    Link to this
  14. 14. Budikturk451 8:48 pm 04/18/2014

    I can’t wait for a new propulsion discovery that would allow us to look for ourselves, (either robotic or manned) For now, I can’t wait to leave, since sadly there’s buggerall here on Earth.

    (Monty fans excuse the spelling)

    Link to this
  15. 15. Mendrys 5:03 am 04/19/2014

    What else should we be forgoing until we cure cancer? What other technology drivers should we extinguish in the pursuit of this mythical idea? Gee, if we only spent about 1/10 of what we do on professional sports (still more than NASA’s budget) we could probably end world hunger, disease and war too. Well, not really but it’s nice to have a fantasy every now and then.

    Link to this
  16. 16. icinmol 6:42 am 04/19/2014

    This is one of the most futile of the research activities. There is no way to ascertain if there is anything interesting let alone life on any of the exoplanets. They are too far away to obtain any scientifically sound data from them. It took over 10 (or so) billion USD to surmise (the most) that Mars has H2O. So what, interstellar space has got plenty of H2O. And now what? These billions would have prolonged (for a couple of years) the survival of say Madagascar. We already do know that that life is (was) unique not only on the Earth but in Solar system and Universe as well.

    Link to this
  17. 17. Richieo 7:41 am 04/19/2014

    IMHO there is a lot of “life” out there although mostly bacteria and lower life forms, I firmly believe searching for “intelligent extraterrestrials” is a total waste of money, time and brain power, that should be directed to more practical areas here on our badly treated and compromised planet…

    Link to this
  18. 18. Bill_Crofut 9:38 am 04/19/2014

    Re: “It’s an article of faith that the planets most likely to harbor life are the planets most like Earth.”

    As an unlettered Traditional Roman Catholic, militant young-Earth Biblical creationist and geocentrist, my chosen status obviously posits me in a tiny minority of the population. My personal position regarding this issue is: The statement, even if true, is incomplete. Another article of faith is the notion that extraterrestrial life exists. Aside from the nonsensical notion of abiogenesis, what possible reason is there to BELIEVE in the existence of extraterrestrial life? It seems unlikely it can reasonably be based on the failed experiments from those of Miller/Urey through Deamer.

    Link to this
  19. 19. rock johny 3:36 pm 04/19/2014

    That’s some crazy speculation in this article. Let’s say we do undertake to make some massive crafts (you’d have to launch an armada) that can support 100 generations or however long it would take; before spending the many trillions that would take, i’d pick a planet that most exactly resembles our own. Not some ‘chubby earth’ with increased gravity and a heavier atmosphere. I’d also pick a list of them grouped ‘close’ together so there is more than one option. That would take a lot more searching to collect that string of pearls.

    Link to this
  20. 20. DarwinRGarcia 3:11 am 04/20/2014

    This search for earth-like planets is only worth while if we find some where we can transplant earth life, or quickly terraform…

    The search for life is incidental… if we do find an “inhabited” planet, there’s no way we’d expose ourselves to microbes that we have no immunity against…

    And wouldn’t it be better to develop the darn propulsion first, or at least on a higher priority?…

    Link to this
  21. 21. Mendrys 3:40 pm 04/20/2014

    It would not make sense to develop a propulsion system to get us to the stars before we decide where we would want to go. Of course, practical interstellar travel may prove too difficult a challenge anyway.

    I think people are missing the point of these searches. They are not an attempt to find habitable planets for US to inhabit; they are looking for planets that could support any kind of life. Kepler is not SETI, it is an attempt to quantify how many other planets are out there and what percentage are close enough to Earth or have Earth like conditions. It appears that the answer, in refutation of what a lot of geocentrists have said, is that Earth is not so special. It’s existence in the solar system does not need some magical set of coincidences that are unlikely to be repeated anywhere else.

    As to Bill Crofut’s question: “Aside from the nonsensical notion of abiogenesis, what possible reason is there to BELIEVE in the existence of extraterrestrial life? It seems unlikely it can reasonably be based on the failed experiments from those of Miller/Urey through Deamer”

    Indeed it is not based on the Miller/Urey experiment, which absolutely was not a failure. The believe that life may exist elsewhere in the universe is based on the fact that we have been coming to the realization thru the centuries that we are not in a special place in the universe. We are only 1 small rock orbiting 1 small star in a countless multitude of others. Why would we NOT believe that it would be possible elsewhere?

    Link to this
  22. 22. bongobimbo 10:52 pm 04/20/2014

    To the person who seems depressed that no exolife may be as intelligent as earth life, I will pose an even more depressing question: “IS THERE INTELLIGENT LIFE ON EARTH?”– or just too many billions of bipedal monkeys, easily suckered and led by the even more brain-handicapped, fooling ourselves?

    Link to this
  23. 23. top_quarck 5:27 am 04/21/2014

    We are soooo… technologically far away to reach Kepler 186 or any star found to harbour earth like planets, that the idea of migrating there once we finish to fuck-up earth is laughable outside the realm of Science Fiction.
    Furthermore cash stripping NASA and other space Agencies ensure it will always be so.
    Also it would be shame to colonise other planets, killing in the process an alien biosphere that could probably do better, and whose only sin is not to be compatible with our biology

    Link to this
  24. 24. gs_chandy 11:15 am 04/21/2014

    The real question is: Does intelligent life on earth exist?

    It’s a moot point indeed, seeing how we humans, in the mistaken belief that we’re the “MASTERS OF THE UNIVERSE!”, are apparently doing our very best to make planet earth uninhabitable by us humans.

    GSC

    Link to this
  25. 25. SAULT18 11:58 am 04/21/2014

    Consider that we find evidence for biological activity stretching back 4 billion years or so, and it may have arisen much earlier. However, life stayed simple, single-celled and microbial until only 500 million years ago. To put things in perspective, life has been on this planet for 90% of its history, but only in the last 10% has it been any more complex or intelligent than a sponge. Therefore, as far as our single example of life in the Cosmos here on Earth, single-celled organisms came about remarkably quickly but complex life took a looooong time to evolve. Therefore, it may be that simple life is relatively common since it can appear so quickly (on at least one planet), while complex life is highly unlikely since it took over 3 billion years of biologic evolution for it to appear.

    While larger planets MIGHT have a more stable climate due to thicker atmospheres, planets like Kepler 186f are also tidally-locked to their host star. This means that one side of the planet is always in daylight and one side is always in darkness. The area on Kepler 186f and others like it that receives the most intense solar radiation will probably be a baked-out cinder that is way too hot for any conveivable life. As you get further away from the planet’s equator and closer to the “night side” things get a little more temperate until things get way too cold for life as well. Specific atmospheric conditions on the planet may change some of these factors, but if a planet is in the “habital zone” of a red dwarf, it will almost always be tidally-locked to the star. And if the daylight side isn’t unbearably hot, then there won’t be enough heat to keep the gases in the atmosphere from condensing out on the night side, quickly disrupting the whole system. And even if things are in equilibrium, this means that the planet will experience constant storms with the intensity that we can scarcely imagine as heat moves from the boiling daytime side to the frigid night side.

    Complex life would have an even harder time handling these issues than it did on Earth. At least here, we had millions of years of relative calm between mass extinction-causing cataclysims.

    Link to this
  26. 26. Jerzy v. 3.0. 6:35 am 04/22/2014

    Can anybody answer, why NASA is looking for habitable planets in 500 light years distance? It would make most sense to explore the nearest stars first, make sure at least that NO habitable planet exists, and proceed futher. Given that humanity would probably want to go there (or at least send an unmanned spacecraft) and distances seem to be the biggest challenge.

    Link to this
  27. 27. Jerzy v. 3.0. 6:38 am 04/22/2014

    @article
    Indeed, there is no reason why Earth should be most suitable place for life. Actually, with the polar caps and large deserts it is not – Earth in the Mesozoic was much more life-friendly.

    Link to this
  28. 28. Bill_Crofut 10:30 am 04/22/2014

    Mendrys (comment 21),

    Re: “…the Miller/Urey experiment, which absolutely was not a failure.”

    “The problem of the origin of life has turned out to be much more difficult than I, and most other people envisioned.”

    [Prof. Stanley L. Miller . 1991. In the Beginning... An interview by staff writer John Horgan. SCIENTIFIC AMERICAN, January, p. 117]

    Re: “…we are not in a special place in the universe.”

    “The assumption of uniformity (of nebular distribution) has much to be said in its favour. If the distribution were not uniform, it would either increase with distance, or decrease. But we would not expect to find a distribution in which the density increases with distance, symmetrically in all directions. Such a condition would imply that we occupy a unique position in the universe, analogous, in a sense, to the ancient conception of a central earth. The hypothesis cannot be disproved but it is unwelcome and would be accepted only as a last resort in order to save the phenomena. Therefore, we disregard this possibility and consider the alternative, namely, a distribution which thins out with distance…readily explained in either of two ways….Both explanations seem plausible but neither is permitted by the observations. The apparent departures from uniformity in the World Picture are fully compensated by the minimum possible corrections for red-shifts on any interpretation. No margin is left for a thinning out. The true distribution must either be uniform or increase outward, leaving the observer in a unique position. But the unwelcome supposition of a favoured location must be avoided at all costs. Therefore, we accept the uniform distribution, and assume that space is sensibly transparent. Then the data from the surveys are simply and fully accounted for by the energy corrections alone–without the additional postulate of an expanding universe.”

    [Edwin P. Hubble, Ph.D. 1937. The Observational Approach to Cosmology. Oxford at the Clarendon Press, pp. 50, 51]

    Please note; the disdain for the centrality of Earth was not based on science, but rather, on philosophy.

    Link to this
  29. 29. SAULT18 11:29 am 04/22/2014

    @ Jersey,

    “Can anybody answer, why NASA is looking for habitable planets in 500 light years distance? It would make most sense to explore the nearest stars first, make sure at least that NO habitable planet exists, and proceed futher.”

    The Kepler space telescope didn’t work that way. It only looked at an extremely small patch of sky and could only find planets whose orbital path caused them to pass in front of their host star from our perspective. It was merely a statistical exercise to see how common planets might be around certain stars. As such, its line-of-sight to its targets incorporated thousands of stars both near and far. Nearby stars like Proxima Centauri, Barnard’s Star, etc. probably weren’t positioned correctly and the line-of-sight to them probably didn’t give a good statistical sampling of stars that the Kepler mission was trying to find.

    Link to this
  30. 30. pbalant 3:56 pm 04/24/2014

    I note that this planet gets 32% as much sunlight as Earth. Won’t that be seriously insufficient to keep temperatures above freezing? I believe the winter solar radiation is not this low in many regions on Earth. I don’t see how this planet can be in a ‘goldilocks’ zone at this level of sunlight.

    Link to this
  31. 31. GraceAndBill 6:25 pm 04/24/2014

    The current technique for identifying small planets is their star’s brightness dipping when the planet transits, or passes in front of their star. This makes it difficult to discover small planets who’s orbital plane is not edge-on with respect to us. Finding habitable planets around larger stars is more difficult because the planets will have longer orbital periods or time between transits.

    Link to this
  32. 32. magneticnorth50 6:52 pm 04/24/2014

    Better than Earth ? Really ? Earth is all we have , and for all practical purposes and the very longterm future it is all we will ever have . Superhabitable ? The Earth is superhabitable , apparently obvious , we’re here discussing it . There is no better planet for life to evolve like us , we are the proof . This is good science fiction to infer what a distant world would be like , and it’s good science to attempt a look ,but that’s about it . We don’t fully understand our own Star and it’s only 93 million miles a way .

    Link to this
  33. 33. Benway 2:36 am 04/25/2014

    pbalant (Comment 30) & SAULT18 (Comment 25)

    At 32% of earthlike radiation Kepler 186f is well out into the cold end of the “Goldilocks zone”. The reason such a low energy flux is still considered “in” is because a heavily greenhousing atmosphere could presumably be compensatory for the sparse input.

    If it is (and I agree it is likely to be) tidally locked, the atmospheric dynamics on a tidally locked planet would be drastically different from anything we are familiar with. Would the sunny side necessarily be a “baked out cinder”? Remember, the energy density doubled on only one side is still only around 64% of earthlike. Would the dark side be cold enough to suck up all the atmosphere as solids? Or would there be a dynamic circulation of gases (a little hydrogen would be a good vehicle, for example) which would go a long way to evening things out? We might think that the “constant intense storms” would be “cataclysms”, but a native life form that found niches there, perhaps starting in cracks or gullies or in soft goo or floating pockets that allowed evolution to progress, would undoubtedly find the local conditions there more like “invigorating”. Cheers.

    Link to this
  34. 34. Benway 3:29 am 04/25/2014

    Bill_Crofut (Comments 18 and 28)

    Edwin Hubble’s speculations from 1937 no longer represent the current state of knowledge re the distribution of galaxies. Your attempt to cite him to support your personal version of “Roman Catholicism” (not at all “traditional”, but rejected by the Papal/Vatican authorities!), is just a travesty.

    Your apparently deliberate misrepresentation of the nature, intent, and even the results of Dr. Harold Urey’s famous experiments is embarrassing.

    When people here (and scientists in general) say “it’s an article of faith” we understand that to be merely a little sardonic hyperbole, denoting the conventional wisdom, which we all negotiate and argue, from evidence and reason, all the time. When you try to bring your “articles of faith” here, you will not receive the hearing you crave. Your self-description as being “unlettered” and “militant” and filled with pride regarding your “tiny minority status” do not make readers here (“Scientific Americans”) want to hear more about your “personal chosen positions”.

    I am trying to suggest, with all due respect, and politely, that you have come to the wrong place with your faith-based beliefs, and that you would be well advised to search for more fertile ground somewhere else. I am sure that almost all the readers of this site agree with this simple suggestion.

    Link to this
  35. 35. lyle918 4:52 am 04/25/2014

    A lot of people seem to have forgotten that without the Moon, life may not have evolved on Earth! And I wonder, if the Moon is moving from Earth, how will that affect live on Earth? Another interesting thing about the Moon is that without the Moon, there would be no solar eclipse!

    Link to this
  36. 36. graycat 7:44 am 04/25/2014

    Jerzy
    To answer your question:
    Can anybody answer, why NASA is looking for habitable planets in 500 light years distance? It would make most sense to explore the nearest stars first, make sure at least that NO habitable planet exists, and proceed futher.

    NASA was using Kepler to find ANY exoplanets it can. They are now still searching the data and I’m sure the researchers chose the easiest [nearest] data to look at first. The fact is Keplers mode of collection can only find a small fraction of the exoplanets out there, no matter the distance. It depends on the planet’s orbit crossing the line of sight between the star and us. For instance the odds that Kepler, if located way out in space, would detect a transit of the Earth across the face of the Sun are about 1 in 360. On top of that Kepler looks in a fixed direction with a field of view of only 12 degrees in width. Of this only 109 square degrees are useful, so only 1/400 of the sky is being observed. Go to Wikipedia for a great article.

    Link to this
  37. 37. Bill_Crofut 8:56 am 04/25/2014

    Benway (comment 34),

    It was not my intention to cite Dr. Hubble as a scientist who supported my view of cosmology. He was only being honest concerning what his observational data demonstrated. Since you have declared the Hubble “speculations” no longer valid, you may wish to share with me the reason(s).
    You may also wish to do yourself a personal favor by learning the meaning of Traditional Roman Catholic. Pope Francis I has publicly belittled the Traditional movement.

    You may wish to “embarrass” me further by explaining my “misrepresentation” of the Urey/Miller experiment.

    You may wish to explain to me why the term “faith” (“sardonic hyperbole”) is used in print in place of “conventional wisdom.” Are you suggesting scientists prefer to play word games? As far as interjecting my Faith on this web page, if it’s considered unacceptable conduct, the author of this essay, and/or the web manager, has the authority to prevent me from posting. You may also wish to share with me where, on this web page, my Faith has been interjected. (the Miller or Hubble quotes?). As for my “prideful” self-description, allow me to state, with all due respect, and politely, you are incorrect. It’s merely a statement of fact which disarms anyone who might wish to accuse me of purposely misrepresenting myself.

    Link to this
  38. 38. MichaelGriessel 5:39 pm 04/25/2014

    It’s really great how we are finding all of these possibly earth like worlds. But does it really matter, if its going to take hundreds of thousands of years to get there?

    Link to this
  39. 39. Char17 5:59 am 04/26/2014

    I cannot believe some of the comments like there is no life other than on our planet. The fact that we exist is the fact that other life forms exist, outside of our planet. Perhaps we will not know of the discovery of different types of life forms outside of our planet in OUR life time, but it IS possible that we will discover it one day or maybe in the distant future. Saying that life does not exist anywhere else in the universe is like saying that the earth is flat. This is my opinion based on the fact that I exist, is proof enough for me to believe that other types of life forms exist. I do believe however, that everyone is entitled to their opinion. I can understand why some people would say that life does not exist outside of our planet based on the fact that we haven’t found any other type/s of life other than life on this planet YET. We (future) WILL eventually find life outside of our planet, but we may never find out in OUR life time.

    Link to this
  40. 40. Benway 3:27 pm 04/27/2014

    Bill_Crofut (Comment 37)

    While you and the pope may have reason to belittle each other, I merely suggest that your comments here are irrelevant to the discussion of the possible habitability of Kepler186f. Just because S.A. doesn’t prevent you from posting is hardly a reason for you to continue wasting your time here.

    To your points:

    1.) Hubble’s remarks have been rendered irrelevant because our observational data have been increased by 4 to 5 orders of magnitude since 1937.

    2.) The Miller/Urey experiments are considered a great success by scientists everywhere as they demonstrated the generation of complex organic molecules from more primitive extrasolar starting points, an important step in abiogenesis, which obviously happened at least once, even though you call it “nonsensical”. Of course you think you have a more “reasonable” alternative. You misrepresent them as failures, why? I can only suppose you think they were trying to “create life”, which is basically a little silly, all around. Why else do you call them “failed”? I’m sure there is nothing that will make you feel embarrassed by your screeds, it is the rest of us who find them so.

    3.) Lastly, scientists will continue to use metaphors and figures of speech like “articles of faith” and continue to have innuendos and veiled accusations (“word games”) thrown at them by devoutly sincere believers such as yourself, but as I have said before, you are wasting your time here, unless you are seeking to be mocked.

    Link to this
  41. 41. scienceastronomy 12:36 am 04/28/2014

    It is a great theological and scientific question of the characteristics of the soul-filled, intelligent, advanced, humanlike species who exist on earths that are better than this earth for life. Did God create the Seraphim, Cherubim, Thrones, Principalities, Archangels, and Angels on better earths. We are learning that our earth is far from the center of our suns habitable zone, as little as only one million miles from the inner edge of a 60 million mile wide habitable zone that finds Mars elliptical orbits average as much as 10 million miles from the outer edge. The main difficulty for Mars life is its .5327 earth diameter and .38 earth gravity. Did God roll out 10 billion habitable zone earths and superearths at different positions in their stars habitable zones and Jesus Christ’s sacrifice is more or less extreme depending on the closeness to either of the edges. His sacrifice here was so extreme because our earth is so close to the inner edge. In the sermon today was mentioned Doubting Thomas touching Jesus’ nail wounds and the spear wound in Jesus side, that were part of Jesus’ resurrected body. In my mind, there is a possibility that during Jesus’ Ascension, the wounds ceased to exist. What is so great about science of the last few centuries is that the scientists, through the evolution of the sciences, are proving The Bible, from the geological changes of our earth to the number of stars in the universe. The noble and good scientists through the Doubting Thomas method are slowly bringing Earths Peoples to a clearer recognition of the supernatural realities inherent in and that grow out of an infinity of universes that exist in as yet unknown relationships in a multitude of dimensions.

    Link to this
  42. 42. Bill_Crofut 9:22 am 04/28/2014

    Benway (comment 40),

    Re: “To your points:”

    1) Whatever observational data you believe has made Hubble’s remarks irrelevant, they would seem to have been confirmed by at least one major observation:

    “The universe has been expanding at a more or less constant rate for billions of years. According to current theory, though, it swelled by the staggering factor of a least ten trillion trillion in size between 10-35 and 10-32 second after the big bang. To distinguish it from ordinary expansion, that expansion-on-steroids is called the inflationary epoch, or just inflation. Inflation is strongly supported by circumstantial evidence, but until now it had not been confirmed by any observational data.
    For decades, though, astronomers predicted that inflation might have left a telltale imprint in the energy distribution of the early universe. That energy, observable today as the leftover heat from those early times, is called the cosmic microwave background…CMB…”

    [Prof. Charles Liu. 2006. Shades of the Past. NATURAL HISTORY, June, p. 66]

    If memory serves, Drs. Penzias and Wilson detected the cmb in whatever direction they aimed their telescope.

    2) Whatever the Miller/Urey experiment in 1953 may have demonstrated, it was not abiogenesis. Keep in mind what may have been the most important starting parameter:

    “The idea that the organic compounds that serve as the basis of life were formed when the earth had an atmosphere of methane, ammonia, water, and hydrogen instead of carbon dioxide, nitrogen, oxygen, and water was suggested by Oparin and has been given emphasis recently by Urey and Bernal.”

    [Stanley L. Miller. 1953. A Production of Amino Acids Under Possible Primitive Earth Conditions. SCIENCE, Vol. 117, p. 528]

    The reason for that parameter was the understanding that oxygen is detrimental to life. Yet, a pair of geologists would seem to have destroyed the parameter:

    “Geological evidence often presented in favor of an early anoxic atmosphere is both contentious and ambiguous. The features that should be present in the geological record had there been such an atmosphere seem to be missing….Ever since the work of Oparin…and the success of the experiments conducted by Miller…the dogma has arisen that Earth’s early atmosphere was anoxic, probably highly reducing…Conjecture and speculation, based on a knowledge of the chemistry of living matter, gave to them the composition of their starting materials, and it would have been surprising if they had not achieved the results they did.”

    [Harry Clemmey and Nick Badham. 1982. Oxygen in the Precambrian Atmosphere: An Evaluation of the geological Evidence. GEOLOGY, March, p. 141]

    3) At least one scientist considered his own use of a faith statement (even if inadvertently) to be improper:

    “We believe that organisms—Well, I shouldn’t say we believe. The good genetic evidence is that there are about 100,000 genes in a human being.”

    [Prof. Kenneth R. Miller. 1997. RESOLVED: THE EVOLUTIONISTS SHOULD ACKNOWLEDGE CREATION. A FIRING LINE DEBATE broadcast December 19. Columbia, SC: Producers Incorporated for Television, transcript, p. 47 (modified transcript available online: http://www.philvaz.com/apologetics/p45.ht)]

    As for wasting my time here, you may be correct, but not for the reason you posted.

    Link to this
  43. 43. SJCrum 5:12 pm 04/28/2014

    As for this item of twin earths, it is the most fantastically thrilling thing in the world, but not as described here. And, for two VERY GOOD reasons.
    For a beginning, the objects that are being seen in space images are not planets at all, but instead, are a burned-out star that is seen orbiting around a second, still-burning star.
    As for the science involved with that, our galaxy is streaking through the universe at light speed, and as that is occurring, our outer stars are colliding with outer stars of the Constellation of Andromeda. In this situation the stars collide, and while a larger star still burns, the other smaller star ends up orbiting. So, that is the real situation. By the way also, all Super Novas are this as well, and stars at the ends of their lives do not explode, but just simply, like candles. just stop burning.
    On the good side, though, and the real other earth-like planet, that does factually exist, and is in the Constellation of Orion. And, roughly six star-diameters to the upper left of the left-most star in Orion’s belt.
    For information about this planet, it is a planet that is far more wonderful than earth, and that because its purpose is to provide a place to live that will last forever. And, this because the God of Creation, not only mad earth as a temporary planet for human development, but made the second planet for the future forever. That planet also has three stars that make it so life there can last eternally.
    As for earth, its star is only a single one, and it will eventually just burn out. So, it’s temporary.
    As for all of the things that appear dangerous here, it would be if we all didn’t have a God that totally loves us. With that existing as factual as fact gets, everyone He loves will be taken to that new-world planet.
    As for any other planets like earth, God didn’t make any others, so they do not exist.

    Link to this
  44. 44. pbalant 2:25 pm 04/29/2014

    @Benway (comment 33)

    Thanks for your response. It does seem a tad exaggerated to say this might be a superhabitable world when it gets 32% of the radiation of earth, and it may well be tidally locked. However, this won’t be the first piece of jouralism to exaggerate for the sake of a headline.

    Regarding your other comments, I appreciate the rational responses.

    Link to this
  45. 45. GLSheridan 1:49 am 06/24/2014

    If we stay where we are – if we never raise our heads and look to the stars – we’re going to stagnate. Humans are a curious species (in both senses of the word. We want to know what’s out there. Not only that, we want to go and experience it first-hand. Isn’t that why Columbus, Magellan, Capt. Cook and the Pilgrim Fathers set out? There are always pioneers, looking forward, moving on. It’s a human strength.
    I know colonising another Earth-like planet isn’t possible yet. The cosmos is too vast, distances too great. But one day, it may be possible. Hope so. Our next logical step is Mars. Volunteers have already signed up. My heart leaps to think of it.
    I find the idea of another habitable planet thrilling. A bit worried by the size of this one – won’t the gravity be too much for humans to bear?

    Link to this

Add a Comment
You must sign in or register as a ScientificAmerican.com member to submit a comment.

More from Scientific American

Scientific American Dinosaurs

Get Total Access to our Digital Anthology

1,200 Articles

Order Now - Just $39! >

X

Email this Article

X