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First Earth-Sized Exoplanet May Have Been Found

Adam Korbitz writes "New Scientist is reporting the extrasolar planet MOA-2007-BLG-192Lb — whose discovery was announced just last summer — may actually be the first truly Earth-sized exoplanet to be identified. A new analysis suggests the planet weighs less than half the original estimate of 3.3 Earth masses; the new estimate pegs the planet's size at 1.4 Earth masses. The planet orbits a small red dwarf star, some 3,000 light-years from here, at an orbital distance of 0.62 astronomical units, about the same distance as Venus from our sun. One significance of the planet's discovery is that it points to the probable ubiquity of smaller terrestrial planets in somewhat Earth-like orbits around red dwarf stars, the oldest and most numerous stars in the galaxy. Here is a video report from the discoverers."

64 of 222 comments (clear)

  1. Re:GNAA by gravos · · Score: 4, Informative

    Although this may be the first Earth-sized exoplanet, 335 exoplanets are already listed in the Extrasolar Planets Encyclopaedia.

    Food for thought.

  2. When can I pack my bags? by erroneus · · Score: 4, Funny

    I'm all about getting the hell out of here!

    1. Re:When can I pack my bags? by azakem · · Score: 2, Insightful

      You should probably pack now and get moving, I hear it's kind of a long flight.

    2. Re:When can I pack my bags? by erroneus · · Score: 2, Funny

      Not as bad as you think... I hope to achieve near light speed within the first twenty-four hours. In your time, I am not entirely sure what that will be, but the question is moot as you may be pretty close to dead by then...and your kids...

    3. Re:When can I pack my bags? by fractalspace · · Score: 5, Insightful

      Remember what we see is a 3000 year old image of the planet. It may not even exist today.

    4. Re:When can I pack my bags? by erroneus · · Score: 3, Funny

      You're like a kid with a pin and a balloon. You just had to ruin it didncha?

    5. Re:When can I pack my bags? by sleeponthemic · · Score: 3, Interesting

      Make sure you put velcro on your tool bag - they've been known to float away.

      --
      I record my sleeptalking
    6. Re:When can I pack my bags? by biocute · · Score: 3, Interesting

      This got me thinking:

      If inhabitants there invented faster-than-light space travel, and arrived on Earth thousands of years ago. Eventually their civilization was destroyed by some freak natural disasters and all techs were lost.

      We are just their descendants, now looking at our home planet?

    7. Re:When can I pack my bags? by Petrushka · · Score: 4, Funny

      Remember what we see is a 3000 year old image of the planet. It may not even exist today.

      It's not clear to me what "today" should mean in this context. Presumably there's a frame of reference in which Earth today and this other planet 3000 years ago are simultaneous ...

      ... er, come to think of it, that frame of reference would be ... here, wouldn't it?

    8. Re:When can I pack my bags? by risk+one · · Score: 4, Funny

      Do not interpret 'tool bag' as a euphemism. World of hurt.

  3. ps June 2, 2008 by MRe_nl · · Score: 4, Informative

    Using standard nomenclature, the star hosting the newly discovered planet is dubbed MOA-2007-BLG-192L with MOA indicating the observatory, 2007 designating the year the microlensing event occurred, BLG standing for bulge, 192 indicating the 192nd microlensing observation by MOA in that year and the L indicating the lens star as opposed to the background star further in the distance. The planet maintains the name but adds a letter designating it as an additional object in the star's solar system, so it is called MOA-2007-BLG-192Lb.

    Hello MOA-2007-BLG-192Lb. How are you? We're fine thank you.
    How's the weather? Would you like to play a game?

    --
    "Kill 'em all and let Root sort 'em out"
  4. might be a lil off topic by ani23 · · Score: 3, Informative

    but how do /.'ers figure out which is the actual link to the article. Case in point this one. there are 5 different links which go to 5 different places. is there one link whihc goes to the actual article or is it just a mashup of information?

    1. Re:might be a lil off topic by Silicon+Jedi · · Score: 3, Insightful

      You really must be new here. Slashdotters don't RTFA.

    2. Re:might be a lil off topic by ceoyoyo · · Score: 2, Informative

      Writing hypertext seems to be a bit of an art form these days. If you've got five pages you want to link to you're not supposed to just pick five random words in your text and turn them into links.

  5. Well... by actionbastard · · Score: 3, Interesting

    MOA-2007-BLG-192Lb ain't LV-426. If you know what I mean...

    --
    Sig this!
    1. Re:Well... by dotancohen · · Score: 2, Funny

      MOA-2007-BLG-192Lb ain't LV-426. If you know what I mean...

      That's not our system!

      --
      It is dangerous to be right when the government is wrong.
  6. Re:announcement by ani23 · · Score: 4, Funny
  7. 'Earth-sized' can be misleading by Vandil+X · · Score: 4, Insightful

    I know the use of the term 'Earth-sized' brings more views, but hopefully the non-science/tech people out there reading it will realize that that is just a physical comparison and not a suggestion that life is present.

    e.g. Venus is also 'Earth-sized' but is highly inhabitable (for life as we know it)

    --
    Up, Up, Down, Down, Left, Right, Left, Right, B, A, START
    1. Re:'Earth-sized' can be misleading by Vandil+X · · Score: 3, Funny

      doh. highly uninhabitable.

      --
      Up, Up, Down, Down, Left, Right, Left, Right, B, A, START
    2. Re:'Earth-sized' can be misleading by morgan_greywolf · · Score: 2, Informative

      Downright inhospitable, in fact, which is -- I think -- the word you were looking for.

  8. Re:GNAA by lorelorn · · Score: 5, Informative
    Not really. The detection methods currently used to find exoplanets mean that the larger and closer the planet is to its parent star, the easier it is for us to find.

    As our techniques become more sophisticated, we will be able to find more planets of a comparable size to our own. Those 335 can be thought of as the 'first wave' of discovered exoplanets. Large bodies close to their parent stars. These planets are interesting for what they can tell us about how solar systems can form.

    The next wave of discovered exoplanets will be smaller, say between the sizes of Venus and Neptune, and therefore far more interesting from the perspective of extrasolar life.

  9. Settle Venus and Mars first. by john.picard · · Score: 2, Interesting

    Why don't we figure out how inhabit to Venus and Mars first, and then look for things farther away? At 3000 light years, it's a bit too far to think of starting a settlement there.

    1. Re:Settle Venus and Mars first. by burning-toast · · Score: 3, Interesting

      Venus will never be a good candidate for habitation unless we build platforms which "float" on its atmosphere's surface due to the close proximity to the sun. Wikipedia has some decent overview here: http://en.wikipedia.org/wiki/Colonization_of_Venus

      Mars is also quite small and does not hold onto its atmosphere very well (which coincidentally means it also doesn't have a strong magnetic field of it's own in which to protect potential inhabitants from solar radiation amongst other things (again due to its size)), so colonizing it will only really be possible if we build sealed enclosures on its surface or find a way to generate a LOT of atmosphere over a long time AND we find a way to protect our self from radiation from space in a feasible manner.

      I am not an educated member in these related fields, but this is the information I have picked up while taking a passing interest in this stuff.

      On top of that, finding other planets which are earth like does not have to happen in an either / or situation with attempting to colonize other planets. Both research paths can and are being pursued at the same time because it takes an entirely different scientist and research field to find extra-planetary bodies than it will to find a way to terraform one.

      - Toast

  10. Earth-sized != Earth-like by Anonymous Coward · · Score: 5, Interesting

    Just because it's an earth-sized planet doesn't mean it's Earth-like. Red dwarf stars are very small (no more than half the mass of the Sun). They don't put out much energy so the habitable zones are very small and very close to the planet. Being so close to the sun makes it likely that the planet would be tidally locked (same side always facing the sun) which isn't so good for life. Finally red dwarf stars often have high stellar variation (sometimes fry you, sometimes freeze you), also not so good for life.

    So exciting, but keep looking.....

    http://en.wikipedia.org/wiki/Habitability_of_red_dwarf_systems

    1. Re:Earth-sized != Earth-like by binarylarry · · Score: 2, Funny

      Don't give me any of that 'Star Trek' crap. It's too early in the morning.

      Bloody smeg head.

      --
      Mod me down, my New Earth Global Warmingist friends!
    2. Re:Earth-sized != Earth-like by dryeo · · Score: 2, Interesting

      One possible way around the tidal locking problem is if the habitable planet is actually a satellite of a larger planet. Or the planet has a satellite like our moon.
      The satellite would be tidally locked to its parent and I'd think that in a relationship like between the Earth and Moon there would be a tendency for them to get tidally locked.

      --
      https://en.wikipedia.org/wiki/Inverted_totalitarianism
  11. So? by bradbury · · Score: 5, Interesting

    If you are familiar with the work of Charlie Lineweaver's group in AU, you would be aware that not only should Earth-like planets exist but that a significant number of them are older, and potentially more advanced than we are. This might then lead you to explore whether or not Matrioshka Brains (forms of civilizations significantly more advanced that our own exist.) And indirectly to an understanding that extremely advanced stellar civilizations have very different heat signatures (or detection signatures) from our own. Thus the detection of an earth-like planet is not that significant. The detection of a star going dark, signaling a civilization making a Kardashev-Type-I to a Kardashev-Type-II transition -- now that would be interesting.

    1. Re:So? by osu-neko · · Score: 5, Interesting

      If you are familiar with the work of Charlie Lineweaver's group in AU, you would be aware that not only should Earth-like planets exist but that a significant number of them are older, and potentially more advanced than we are.

      Familiarity with Lineweaver's work does not make one "aware" of that "fact", it merely makes one aware that some people have argued that that is the case. :p

      Lineweaver, Davis, and such have proposed a number of ideas which are intriguing, but it's all on very tiny and shaky foundations. Not saying they're wrong, but if they're reasonably close to right, that's more luck than anything, given the sample size of there real data it's all based on (e.g. estimating how many Earth-like planets develop life in their first billion years based on the one and only example we have of it happening).

      --
      "Convictions are more dangerous enemies of truth than lies."
    2. Re:So? by Anonymous Coward · · Score: 4, Funny

      If you are familiar with the work of L. Ron Hubbard's group in OT8, you would be aware that not only should Earth-like planets exist but that a significant number of them are older, and potentially more advanced than we are. This might then lead you to explore whether or not the Marcab Confederacy (form of civilization significantly more advanced that our own exist.) And indirectly to an understanding that extremely advanced stellar civilizations have very different Body Thetans (or Operating Thetans) from our own. Thus the detection of an earth-like planet is not that significant. The detection of a star going dark, signaling a civilization making an R5-Implants to an R6-Implants transition -- now that would be interesting.

    3. Re:So? by sleeponthemic · · Score: 2, Funny

      you would be aware that not only should Earth-like planets exist but that a significant number of them are older

      Haha, foolish human. Everybody knows that Earth holds the record for the oldest planet at a 6000 years.

      --
      I record my sleeptalking
    4. Re:So? by ceoyoyo · · Score: 2, Informative

      For those who like to see some actual observations back up speculation, detection of an Earth-sized planet is a big deal. Until we see some, we can't really say how many such planets exist. Once we see one we know that we can detect them. Once we see two, we can start to make (poor) estimates of how many there are. From there the estimates only get better.

      I'm sure Dr. Lineweaver would agree, see as how the first research interest listed on his web page is "the analysis of recent exoplanet data and its ability to address the question 'Is our Solary System typical?'" (http://www.mso.anu.edu.au/~charley/)

    5. Re:So? by burning-toast · · Score: 2, Insightful

      Along that same line of logic: How come we haven't found them and said "Hi!"? I would suggest that problems we face may not be terribly different from problems other potential civilizations have come across (should they exist).

      I'm sure there are plenty more issues we have yet to discover with long-range communications through space. Let alone the process of finding other intelligent beings to communicate with or finding an intelligible way to communicate between two entirely different species... Don't let the dreamed up solutions from Sci-Fi movies make you think there are easy or even possible solutions to those problems.

      Ever try and carry on a conversation with a dolphin for example? How about over thousands of light-years worth of space?

      - Toast

    6. Re:So? by sleeponthemic · · Score: 3, Funny

      Irony

      --
      I record my sleeptalking
    7. Re:So? by adavies42 · · Score: 5, Interesting

      i once saw this basic argument used to infer the existence of workable ftl. it goes something like this:

      1. conquering the whole galaxy (via generation ships or von neumann machines or whatever) takes only a few million years
      2. we're unlikely to be the absolute oldest civilization in the galaxy
      3. we do not appear to have been conquered
      4. the only feasible way to block conquest is a federation with a prime directive
      5. the only way to hold a federation together is ftl
      6. therefore ftl exists. qed.

      now obviously there are lots of holes in this, but i find it at least as compelling an answer to the fermi paradox as "they've all transcended"/"they're hiding in their dyson spheres".

      --
      Media that can be recorded and distributed can be recorded and distributed.
      -kfg
  12. Quick quiz by The+Bungi · · Score: 5, Interesting

    Since the strength of the gravitational field of a planet is a factor of its mass, and the gravitational pull on the surface is in direct relation to the distance from the center of the planet... could it not be possible to have a planet the size of say, Neptune, with a geological makeup similar to the Earth, that has a lower mass and therefore the acceleration at the surface is exactly 1g (as we understand it here on Earth). That is within the bounds of physics, is it not?

    Or maybe the effective gravity is stronger, but the planet spins faster. Faster days as well?

    The problem I guess would be the existence of a formation process that actually creates a planet with such a large surface but happens to be mostly rock instead of mostly gas (supposedly gas giants are "failed stars"). If it has a molten iron core, would it not collapse in on itself?

    Interesting, imagine a planet with the surface composition and atmosphere of Earth (and supposedly biomass) but 10 or more times the surface. That would be amazing.

    1. Re:Quick quiz by Daniel+Dvorkin · · Score: 3, Informative

      could it not be possible to have a planet the size of say, Neptune, with a geological makeup similar to the Earth, that has a lower mass and therefore the acceleration at the surface is exactly 1g

      It's entirely possible for a gas giant -- according to Wiki, the "surface gravity" of Neptune is 1.14g, and for Uranus it's 0.886g. I put "surface gravity" in quotes here for obvious reasons, but something like the "cloud city" in The Empire Strikes Back would be quite livable on either of these planets. As for rocky planets, it seems doubtful. Anything solid that was of Neptunian size and mass would, I think, very quickly collapse into a much more compact mass with much higher surface gravity.

      --
      The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
    2. Re:Quick quiz by ceoyoyo · · Score: 2, Informative

      A planet with the same composition as Earth but with 10 times the mass will NOT have 10 times the surface gravity. It's radius will be larger, so the surface gravity will be less than 10x, but greater than 1x.

    3. Re:Quick quiz by samkass · · Score: 3, Insightful

      according to Wiki, the "surface gravity" of Neptune is 1.14g, and for Uranus it's 0.886g. I put "surface gravity" in quotes here for obvious reasons, but something like the "cloud city" in The Empire Strikes Back would be quite livable on either of these planets.

      Assuming, of course, that you don't mind being crushed to pulp, or have some way of surviving 1000mph windstorms. Of course, for energy you'd have all the natural gas you could ever wish for, if only there were some oxygen around to burn it with.

      --
      E pluribus unum
    4. Re:Quick quiz by Anonymous Coward · · Score: 3, Informative

      It would have to be composed of dramatically different mix of elements; low density due to structural differences would not be possible beyond some fairly small radius -- far, far, smaller than Earth. Basically, once an object is large enough that gravity can form the object in to a sphere, the mass of the object will be high enough to obliterate any pore space beyond a fairly shallow depth. The details can be fairly readily calculated knowing the strength of rock, which is indeed well known for rock types that would constitute the bulk of any likely Earth-size planet.

      The likelihood of maintaining a structurally low density planet, beneath a very shallow layer at the top of the planet's crust, is further reduced due to the problem of heat. Rock weakens as heat increases, and heat increases with depth. Even a geologically dead planet would have or have had considerable heat at depth at some point in its life, at which time the low density material would have collapsed.

      This also ignores how such a body could form, certainly beyond my creativity to imagine.

      A planet simply is not going to be low density by virtue of its structure. You need different materials.

      The bulk of the Earth is made of silicate rock, iron, and nickel, giving it an average density of about 5.5 grams per cubic centimeter. You could build a planet of somewhat lower density using various kinds of ice.

      The problem there, however, is that you probably won't be able to achieve density much lower than something between 1.2 and 1.8 grams per cubic centimeter (the precise amount depends on how exotic a composition you're willing to invent and its total mass -- substances will possess increasingly dense crystal structures as the material is put under higher pressure). That's a lot less than Earth, but not close to the level's originally suggested. And this planet certainly isn't going to look an awful lot like Earth. It'll look more like Titan.

    5. Re:Quick quiz by Daniel+Dvorkin · · Score: 2

      Crushed to a pulp? "Surface" pressure on Neptune is 1 bar, same as Earth. For power, if you have controlled fusion there's no lack of hydrogen ... Weather might be a problem, although if you stay high enough you should be able to avoid the worst of it, and float with the rest.

      --
      The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
    6. Re:Quick quiz by dotancohen · · Score: 3, Informative

      g = G*Me/(Re)^2

      Now you want something with the same g, but 10 times the mass?
      G*10*Me/R^2 = g = G*Me/(Re)^2

      It works out that:

      R = sqrt(10)*Re or a little over three times the radius. So a planet with ten times the mass of Earth, and three times the radius, would have about the same gravitational pull at the surface.

      --
      It is dangerous to be right when the government is wrong.
    7. Re:Quick quiz by MarkusH · · Score: 2, Funny

      Ah, but the volume of an object increases as a cube, so if we increase the sphere so that the increase in the radius is 3, that would increase the volume by 27. Since we want to have a surface gravity similar to earth, that would mean the density of the planet to be about 2.04. (mass increases by 10, volume increases by 27, density of the earth is approximately 5.52)

      Interestingly, that is very close to the range of the bone density of many animals, so the answer is obvious. We need to find the skeletal remains of a spherical space whale that is 3 times the size of the earth, and immigrate there.

      Of course, with my luck, it would already be inhabited and I would be put to work in the calcium mines.

  13. On the flip side... by interactive_civilian · · Score: 5, Insightful

    Earth might be broken in some ways, but it is (most likely) a lot better environment than anything else out there. Earth is a far better starting position than Mars or whatever and fixing what's broken here would be far more achievable than trying to build a viable human-sustaining ecosystem on some other planet.

    On the flip side, the spin-off technologies from making a sustainable habitat off planet would probably do wonders for improving the quality of life on planet. Everything from medical technology to air scrubbing and environmental cleanup, food and nutrition to understanding of local ecology and balancing it, energy technology to waste disposal and recycling, and probably much more.

    --
    "Empathise with stupidity, and you're halfway to thinking like an idiot." - Iain M. Banks
    1. Re:On the flip side... by damasterwc · · Score: 2, Insightful

      who modded this insightful? you think genocide is insightful?? you want to wipe out 6 billion people... the british eugenics movement must be proud... their disgusting thoughts and world wildlife fund are really making an impact on the retards of the planet today...

    2. Re:On the flip side... by db32 · · Score: 3, Insightful

      Good luck on removing conflicting ideologies and justifications for armed conflict. But it is certainly a nice thought. At least we will have a clean place to bury the dead. :)

      --
      The only change I can believe in is what I find in my couch cushions.
    3. Re:On the flip side... by Anonymous Coward · · Score: 2, Interesting

      On the flip side, the spin-off technologies from making a sustainable habitat off planet would probably do wonders for improving the quality of life on planet.

      If the spin-off technologies are so valuable, why not fund the research, skip making the actual trip, and wind up with better technology without going anywhere? Do everything except build the final vehicle and we save lots money and get cool technology.

    4. Re:On the flip side... by im_thatoneguy · · Score: 2, Informative

      All of which could be designed to "hypothetical" standards without the imminent fear of death.

      Or... you could actually threaten people with death and force them to survive in a large Warehouse full of nerve gas.

      Creating a 'space' environment in which technology is required to keep a crew alive is readily available on earth. It has the added benefit of saving hundreds of millions of dollars in rocket fuel to launch it somewhere it's not really needed.

      Low gravity is the only condition I'm aware of that can't be readily simulated on terra firma. (Ignoring flight control, navigation, starship testing stuff. None of which is terribly useful in improving a more sustainable habitat here on earth.)

      Save the tens of millions of dollars that would be spent launching our marginally useful environment improvement technology and put it straight into R&D.

    5. Re:On the flip side... by albyrne5 · · Score: 2, Informative

      Dude, he say "wind" the population down, not massacre them. We're all gonna die, may as well plan to make the future better for the ones who have yet to live.

  14. Re:GNAA by Nimey · · Score: 4, Funny

    This must be the first Slashdot post with a GNAA subject line that's been modded "informative" in years.

    --
    Hail Eris, full of mischief...

    E pluribus sanguinem
  15. Sized? by nog_lorp · · Score: 2, Interesting

    I'm used to size meaning volume...

    Otherwise you might say a bullet is the size of 100 feathers...

    1. Re:Sized? by ceoyoyo · · Score: 3, Insightful

      When the only thing you can measure is mass, every ambiguous noun begins to look like a synonym for mass.

  16. who cares about the discoverers? by Gothmolly · · Score: 2, Interesting

    I want to see video of the planet.

    --
    I want to delete my account but Slashdot doesn't allow it.
  17. Re:Ummm by Nefarious+Wheel · · Score: 4, Funny
    I want to live in a garden and have the universe as my toy, spinning at my whim and containing all my dreams, pets and machines. I want green, sunlit gardens and waterfalls with Waldos stepping through the murk and smoke of sunless moons, digging my wealth. I want iced tea, fast machines, flying cars and friendship that never dies. And I want another planet to study. Yes, another planet.

    But the doctor says I can't have iced tea. He said nothing about the rest.

    --
    Do not mock my vision of impractical footwear
  18. Re:Ummm by PTBarnum · · Score: 5, Insightful

    I anticipate that someday science will advance to the point where ordering up your own private garden planet, and a fleet of intelligent and loyal robots to tend it for you, is considered routine. A wormhole network connecting your plant to a set of resource-rich sunless moons will be included at no extra charge.

    Everyone will have eternal life and health, lots of friends, and be allowed by their doctors to drink all the ice tea they want.

    But we still won't have flying cars.

  19. Re:Ummm by ppanon · · Score: 3, Interesting

    Not necessarily. The problem is the "unthinking" masses of humanity. We have it really easy on Earth compared to the artificial environments that we would need to sustain ourselves in space. First we'll have to figure out a long-term approach for how to reliably protect our reproductive organs from ambient high-energy radiation once away from the Earth's magnetic field so that independent colonies don't get overwhelmed by birth defects. Eventually though, living in space would apply a whole new set of evolutionary pressures for survival and human space-farers would have to adapt. If we survive long enough to permanently colonize space, it would probably transform that part of humanity that would make it into space by making it much more aware of risk evaluation and risk taking, and general incompetence will get weeded out fairly quickly and ruthlessly by the ambient dangers of space.

    It might take a few failed colonies at first, but eventually a society would evolve a way to ensure that happens. Perhaps mandatory civil service that involves external colony maintenance as a requirement for political office? Or maybe even the same for obtaining the voting franchise - a sort of Starship Troopers lite.

    In fact, if you were a space-going race you probably wouldn't want to establish contact with a species that hadn't already gone through that winnowing out process. I would even go so far as to say that that difference might eventually lead to true divergence of humans into two species: the earth-bound and the space-faring.

    If "we" get out there, the people that colonize another planet probably won't be the same "people" that are messing up Earth right now because those people wouldn't survive long enough to make it that far. Yeah, it's kind of an elitist view, but evolution is the ultimate meritocracy and, in very harsh environments, the people that forget that don't stay in the gene pool long.

    --
    Laissez lire, et laissez danser; ces deux amusements ne feront jamais de mal au monde. - Voltaire
  20. Red Dwarfs & Life: the good and the bad of it by cmholm · · Score: 4, Informative

    Specifically, Earth biology wouldn't do well orbiting a red dwarf. Red dwarfs emit most of their energy via thermal convection, rather than (like our Sun) via radiation. This leads to lots of radiation bursts when convection cells reach the surface. At 1 A.U., no big deal. But, at an orbit close enough to keep - say - Earth as warm as it is orbiting the Sun, life would get hammered.

    This isn't to say that *something* wouldn't evolve. It's just that at a basic level, it wouldn't resemble anything we're familiar with. And, given how long a red dwarf stays in the Main Sequence, there'd be billions upon trillions of years to simmer the soup 'til it was just right.

    --
    Luke, help me take this mask off ... Just for once, let me butterfly kiss you with my own eyes.
  21. Re:GNAA by dotancohen · · Score: 2, Funny

    This must be the first Slashdot post with a GNAA subject line that's been modded "informative" in years.

    That's because all the new heres thought GNAA is the crossover interest organization of their dreams: the GNU Astronomy Association.

    --
    It is dangerous to be right when the government is wrong.
  22. Re:GNAA by dotancohen · · Score: 2, Insightful

    Which just goes to show the moderators either don't read or don't agree with the guidelines.

    No, it goes to show what people will do for a cheap +5 informative. Why did the GGP post as a reply to the flame? To be at the top of the page. And what did his link to the 300+ planets have anything to do with TFA? That's a planet, these are planets, +5 Informative in no time!

    I'm all for voting things up rather than down, but in cases like this, the entire thread needs to be modded to oblivion.

    Agreed.

    --
    It is dangerous to be right when the government is wrong.
  23. Re:Ummm by Anonymous Coward · · Score: 3, Funny

    Or these colonists... let's call them 'pilgrims'... will become so in touch with deep space that they will be able to fly without the need for a nav computer.

    Later a civil war will break out only to be interrupted by a viscous race of aliens bent on universal domination.

     
    So a race of thick gooey beings is going to dominate the universe? What happens when you freeze them? Do they turn into popsicles?

  24. Re:Ummm by TheTurtlesMoves · · Score: 2, Funny

    Or duke nukem forever.

    --
    The Grey Goo disaster happened 3 billion years ago. This rock is covered in self replicating machines!
  25. Re:Red Dwarfs & Life: the good and the bad of by Random+Walk · · Score: 4, Informative

    Uhh.. pardon me, who moderated this insightful?

    All low-mass stars, including the Sun and ranging up to F-Type stars (about 1.7 times solar mass) have an outer convection zone (meaning that outside the core, and up to the surface, energy is transported by convection). There's nothing 'bursty' in that mechanism.

    Hard radiation of low-mass stars is generated in the corona, which is heated by magnetic reconnection events (the magnetic equivalent of a short), leading to sudden release of the energy stored in magnetic fields. This is what is called 'stellar activity': starspots, flares, X-ray radiation, ...

    Some red dwarfs are indeed much more active than the Sun, many are not. Activity is generally connected to the age of a star since magnetic fields are generated by a dynamo mechanism, and stars spin down slowly as they are aging, leading to a less efficient dynamo and a decrease of activity.

  26. Re:Red Dwarfs & Life: the good and the bad of by dfunk · · Score: 2, Informative

    And, given how long a red dwarf stays in the Main Sequence, there'd be billions upon trillions of years to simmer the soup 'til it was just right.

    life cycle of a red dwarf is around 100 billion years. trillions of years is out of the question. heck, the universe is only around 15 to 20 billion years old

  27. Not Funny, mod (+5, Possibly True)... by mangu · · Score: 2

    1. conquering the whole galaxy (via generation ships or von neumann machines or whatever) takes only a few million years
    2. we're unlikely to be the absolute oldest civilization in the galaxy
    3. we do not appear to have been conquered
    4. the only feasible way to block conquest is a federation with a prime directive
    5. the only way to hold a federation together is ftl
    6. therefore ftl exists. qed.

    The funny thing is that you were modded funny, but this argument is one of the best there is to explain the Fermi paradox.

    Assuming intelligent races evolve independently all through the universe, what is the probability that a race without a highly evolved sense of ethics would have conquered and colonized our planet long ago?

    I can see only two possible answers to the problem: either the probability of an intelligent species evolving is so extremely small that we are the first to appear in the known universe (or at least in our local galaxy cluster), or FTL exists and a prime directive is in effect.

    Considering the amount of exo-solar planets being found, the number of planets seem very big. Considering our own planet system wasn't one of the first to appear, and that advanced animals already existed here 65 million years ago when they were wiped out by a freak accident, one should say that the probability of being the very first intelligent species doesn't seem to be that high.

    Of course, there are other factors to consider. Maybe the moon was fundamental in the process of life arising, by keeping plate tectonics active, which causes a protective magnetic field to form in the earth. We don't know yet what factors are needed for life to exist, but at this time I wouldn't disregard the FTL + prime directive argument as just "funny".

  28. Re:Ummm by Kelbear · · Score: 2, Insightful

    Evolution will happen anyway based on who ends up living and who ends up dying.

    If a sickly individual survives to procreate due to the medical technology of his culture, while a healthy one dies because his culture didn't have the medical technology to help him recover from a minor accident. Then the sickly individual's culture survives and grows while the healthy individual's culture has shrunk.

    The determining factor of who lives and who dies in this case wasn't the health of the individual, but the culture's ability to provide medical support. If this trend continues, then cultures that can successfully provide medical support will thrive while those that can't, will dissolve. If medical support grows into a burden that drags down the society, then selection based on health may come back into play.

    Potential for intelligence and social cooperation leading to technological advances is a trait which yields the benefit of medical technology. Being healthy enough not to get sick is a different way to get around the problem. Natural selection will still guide evolution in this case.

    You could even see the medical technology as an evolved immune system for the cultural entity.