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Space Science

First Earth-Sized Exoplanet May Have Been Found 222

Posted by kdawson
from the but-not-as-we-know-it dept.
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."
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First Earth-Sized Exoplanet May Have Been Found

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  • by erroneus (253617) on Monday January 19, 2009 @08:57PM (#26523269) Homepage

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

    • 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.
      • by interactive_civilian (205158) <mamoru@@@gmail...com> on Monday January 19, 2009 @09:40PM (#26523679) Homepage Journal

        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.

        • by db32 (862117) on Tuesday January 20, 2009 @01:26AM (#26525407) Journal
          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. :)
        • Re: (Score:2, Interesting)

          by Anonymous Coward

          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.

        • Re: (Score:3, Informative)

          by im_thatoneguy (819432)

          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

      • Re:Ummm (Score:5, Funny)

        by Nefarious Wheel (628136) on Monday January 19, 2009 @11:31PM (#26524623) Journal
        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.

        • Re:Ummm (Score:5, Insightful)

          by PTBarnum (233319) on Monday January 19, 2009 @11:45PM (#26524733)

          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.

    • Re: (Score:2, Insightful)

      by azakem (924479)
      You should probably pack now and get moving, I hear it's kind of a long flight.
      • Re: (Score:3, Funny)

        by erroneus (253617)

        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...

        • but the question is moot as you may be pretty close to dead by then...and your kids...

          I don't see how his personal relationship with his kids influences this thread, but I still find it commendable if he is close to them.

          On the other hand, I find his "talking to the dead" crap rather appaling

          (I see that mods got points to burn, so I figured: what the heck?)

    • by fractalspace (1241106) on Monday January 19, 2009 @09:44PM (#26523709)
      Remember what we see is a 3000 year old image of the planet. It may not even exist today.
    • by sleeponthemic (1253494) on Monday January 19, 2009 @10:13PM (#26524015) Homepage
      Make sure you put velcro on your tool bag - they've been known to float away.
    • Re: (Score:2, Interesting)

      by jamesh (87723)

      3000 light years means that we are seeing it as it was 3000 years ago. If you could get to the speed of light right now, it would be 3000 years until you got there (assuming that the relative distance between us is roughly constant). But you can't go that fast, you'd have to go a lot slower than that.

      In the next 3000 years we are sure to develop much faster methods of travel, so will will overtake you (i'll wave as we pass) and when you get there all the hot alien babes will be taken.

  • ps June 2, 2008 (Score:5, Informative)

    by MRe_nl (306212) on Monday January 19, 2009 @09:02PM (#26523313)

    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?

  • by ani23 (899493) on Monday January 19, 2009 @09:04PM (#26523323)
    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?
    • Re: (Score:3, Insightful)

      by Silicon Jedi (878120)
      You really must be new here. Slashdotters don't RTFA.
    • Re: (Score:3, Informative)

      by ceoyoyo (59147)

      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.

  • Well... (Score:4, Interesting)

    by actionbastard (1206160) on Monday January 19, 2009 @09:05PM (#26523327)
    MOA-2007-BLG-192Lb ain't LV-426. If you know what I mean...
    • You won't know that for sure unless you set down there on Company orders. My advice? Don't.

    • I don't care as long as they got good curry!
    • Re: (Score:3, Funny)

      by dotancohen (1015143)

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

      That's not our system!

  • by Vandil X (636030) on Monday January 19, 2009 @09:07PM (#26523371)
    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)
    • by Vandil X (636030) on Monday January 19, 2009 @09:08PM (#26523375)
      doh. highly uninhabitable.
    • by ceoyoyo (59147)

      What term would you suggest?

      Earth-like is a fuzzy phrase that gets used sometimes when someone wants to generate some hype. Earth-sized is pretty specific. Any undue excitement is entirely the fault of the reader.

      A Venus type orbit around a red dwarf is probably pretty chilly.

    • Uninhabitable. See also inflammable.
    • Specifically, Earth biology wouldn't do well orbiting a red dwarf [wikipedia.org]. 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.

      • by Thanshin (1188877)

        Red dwarfs emit most of their energy via thermal convection [...] 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.

        Crispy chicken?

      • by Random Walk (252043) on Tuesday January 20, 2009 @06:47AM (#26526859)

        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.

  • 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.
    • > Why don't we figure out how inhabit to Venus and Mars first...

      Go right ahead. No one is stopping you.

      > ...and then look for things farther away?

      Because that is what some people want to do? You needn't look if it bothers you.

      > At 3000 light years, it's a bit too far to think of starting a settlement there.

      I wasn't aware that anyone was doing so.

    • by burning-toast (925667) on Monday January 19, 2009 @11:34PM (#26524635)

      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 [wikipedia.org]

      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

      • I didn't see anything in that Wikipedia article talking about magnetic fields. I would think it would be more important for a planet closer to the sun than earth (i.e. Venus) to have a strong magnetic field to protect us weak Earthlings from the stronger solar radiation that Venus would have to have (being closer to the sun and all). I think that particular article is more wishful thinking than anything else (gasp!!! on Wikipedia???). ;)
      • by cjsm (804001)
        I always thought is was a shame Venus isn't in the orbit that Mars is. It potentially could have been a very livable planet.
      • by StarkRG (888216)

        The proximity to the sun has nothing to do with Venus's atmosphere or and very little to do with its extreme heat. In fact, if its atmosphere [wikipedia.org] was more like Earth's (density and makeup) we might be able to live there without too much trouble. (it wouldn't really be that much warmer)

        The prevailing theory of the source of planetary magnetic fields is Dynamo Theory [wikipedia.org], has nothing to do whatsoever with atmospheres (except in the case of stars and gas giants).

        The theory about Mars is that when its core was still mo

  • So? (Score:5, Interesting)

    by bradbury (33372) <Robert@Bradbury.gmail@com> on Monday January 19, 2009 @09:25PM (#26523559) Homepage

    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.

    • Re:So? (Score:5, Interesting)

      by osu-neko (2604) on Monday January 19, 2009 @09:53PM (#26523793)

      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).

      • But one has to expect the production of an argument. And one would need to take into account how many times earth has wiped out life (or at least set it back a significant number of years).

        And then one needs to ascertain what fraction of planets are incomplete in this respect. To that degree the Drake Equation is incomplete.

    • Re:So? (Score:4, Funny)

      by Anonymous Coward on Monday January 19, 2009 @09:53PM (#26523803)

      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.

    • by QuantumG (50515) *

      Or collecting solar power is considered so primitive to an "advanced" civilization that your prediction that stars are going to blink out from them building solar collectors around them is just naive.

    • Re: (Score:3, 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.

    • Re: (Score:3, Informative)

      by ceoyoyo (59147)

      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 a

    • by 0xdeadbeef (28836)

      If civilizations are that common, then the threat of attack by competing civilizations is more pronounced, therefore survivors will go to great lengths to hide themselves.
      We should assume that our simple technology will never detect a Type-II civilization because they would never announce their presence so obviously as by enclosing a star.

    • Re:So? (Score:5, Interesting)

      by adavies42 (746183) on Tuesday January 20, 2009 @03:07AM (#26525865)

      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".

      • 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 para

  • Quick quiz (Score:5, Interesting)

    by The Bungi (221687) <thebungi@gmail.com> on Monday January 19, 2009 @09:27PM (#26523581) Homepage

    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.

    • by cdrguru (88047)

      You are missing something.

      If a planet has a geological makeup like Earth but is 10x the size, then it will have 10x the mass have a surface gravity 10x that of Earth.

      A gaseous planet 10x the size of Earth might well have a surface gravity (such as it is?) that of Earth as it might be about the same mass.

      Either way, I wouldn't like to go there. A planet with a 10G gravitational constant wouldn't be my idea of a good time, although it might be fun to stand off a ways and see what was going on there. A long

      • Re: (Score:3, Informative)

        by ceoyoyo (59147)

        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.

      • 10x the size != 10x the mass. That would be more than 1000x the mass. 10x the volume would be more than 10x the mass (due to increased core density of a larger object of similar composition).

        Finally, 10x mass does not produce 10x surface gravity, since volume is not constant.

        Basically, you're just making stuff up, and doing a poor job of that.

        You can't have a gaseous planet with the mass of earth at 10x the radius of the earth--the density and pressure profiles won't work.

    • Re:Quick quiz (Score:4, Informative)

      by Daniel Dvorkin (106857) * on Monday January 19, 2009 @09:59PM (#26523865) Homepage Journal

      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.

      • Re:Quick quiz (Score:4, Insightful)

        by samkass (174571) on Monday January 19, 2009 @10:52PM (#26524319) Homepage Journal

        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.

        • 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.

    • by ceoyoyo (59147)

      Sure. Neptune itself has a surface gravitational acceleration of exactly 1g, if you define "surface" creatively enough.

      If you want a solid surface, you're probably aiming a little high with something Neptune-sized. You could postulate a planet made entirely out of less dense materials, with very few metals and such, but realistic solid planet building materials don't have a really huge density range.

      You can have surprisingly massive planets of terrestrial-like composition with surprisingly low surface acc

    • Re:Quick quiz (Score:4, Informative)

      by dotancohen (1015143) on Tuesday January 20, 2009 @03:07AM (#26525867) Homepage

      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.

      • Re: (Score:3, Funny)

        by MarkusH (198450)

        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 r

  • Sized? (Score:3, Interesting)

    by nog_lorp (896553) * on Monday January 19, 2009 @10:35PM (#26524173)

    I'm used to size meaning volume...

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

  • by Gothmolly (148874) on Monday January 19, 2009 @10:48PM (#26524283)

    I want to see video of the planet.

    • by StarkRG (888216)

      That would be rather boring, it would be little more than the star wobbling a pixel or two in high resolution.

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