Stories
Slash Boxes
Comments
Search

News for nerds, stuff that matters

Slashdot Log In

Log In

Create Account  |  Retrieve Password

Smallest Planet Outside Our Solar System Found

Posted by Zonk on Thu Apr 10, 2008 03:41 PM
from the hard-to-spot-with-all-the-space-dust dept.
Space Science
mikkl666 writes "Following the recent story about the discovery of the youngest planet outside our solar system, Spanish researchers now report that they found the smallest exoplanet observed so far. The planet, known as GJ 436c, was found by analyzing distortions in the orbit of another, larger planet, and its radius is only about 50 percent greater than the Earth's. The scientists are confident that their new method will lead to a series of further discoveries: 'I think we are very close, just a few years away, from detecting a planet like Earth.' You can also reference the the original paper online for further details."
+ -
story

Related Stories

[+] Youngest Planet Discovered 182 comments
qazsedcft writes "BBC is reporting that Astronomers have discovered what appears to be the youngest planet, being less than 2000 years old. If this proves to be true it could challenge our models of solar system formation."
Submission: Smallest Planet Outside Our Solar System Found by mikkl666 (1264656)
This discussion has been archived. No new comments can be posted.
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.

Smallest Planet Outside Our Solar System Found 50 Comments More /

 Full
 Abbreviated
 Hidden
More
Loading... please wait.

  • Analyzing distortions? (Score:5, Funny)

    by monkeyboythom (796957) on Thursday April 10 2008, @03:49PM (#23029524)

    So you are saying that I can deduce a small child hovering around an obese parent by the way the bigger person's fat jiggles? Brilliant! Now if it only works on fat chicks, then I can discover if they have a hot, smaller female friend nearby...

    • So you're saying that the bigger planets are going to start shooting at us and trying to get us to go home with them when we send manned missions to the Earthlike planet?

      • So you're saying that the bigger planets are going to start shooting at us and trying to get us to go home with them when we send manned missions to the Earthlike planet?

        Bloody hell! I've had a few desperate fat girls try n chat me up before, but never had one pull out a gun n start firing at me to get me in bed. What sort of bars do you hang out in??



        If your curious, yes I did fuck those desperate fat girls, and the ugly ones too, hey, gotta get it while you can, n ugly girls need meaningless 1 night stands too!

    • Re:Analyzing distortions? (Score:5, Funny)

      by $RANDOMLUSER (804576) on Thursday April 10 2008, @04:03PM (#23029676)
      Nah. With chicks, it's just the opposite. The small hot ones are always orbited by larger ones.
      • "Follow your dreams. You can reach your goals. I'm living proof. Beefcake! BEEFCAAAAAKE!"
  • I claim this planet on behalf of Mars!

  • Hal Clement (Score:5, Funny)

    by jdigriz (676802) on Thursday April 10 2008, @03:51PM (#23029536)
    I think we have a Mission of Gravity here. 5x the mass of earth but only 50% more radius? I for one, welcome our Mesklinite Overlords.

    • Re: (Score:3, Insightful)

      by Toonol (1057698)
      Remember, if you hold density constant, an increase in radius translates to a power of three increase in volume, because it's expanding through three dimensions. A 50% increase in radius would result in a (1.5 ^ 3) 3.375 increase in mass. So, a five-fold increase in mass isn't that unreasonable; it's only a 48% increase in density. That's a lot, but you don't have to resort to white-dwarf style matter densities.

      At 5x mass and 1.5x radius, I believe the surface gravity would only be about 2.2 g's.

        • Re: (Score:3, Insightful)

          by iNaya (1049686)
          I'm sure we'd have no problem with that sort of technology by the time we actually reached that planet.

          • Re: (Score:3, Insightful)

            by cjsm (804001)
            Well, besides humans, this would also aply to any intelligent life that might evolve on such a planet. Would rocket technology be sufficient to get off a planet with two or three times the gravity of earth? At point would the gravity be too great for rocket technology to work?

            I'm sure we'd have no problem with that sort of technology by the time we actually reached that planet.

            Well, that's sort of a meaningless answer, since your talking about technology that doesn't exist either in reality or in th
  • what is the minmum possible size/mass of a planet according to the new definition of 'planet'?

    • Re: (Score:3, Informative)

      by 4D6963 (933028)

      what is the minmum possible size/mass of a planet according to the new definition of 'planet'?

      I don't know about that (well I do know but you could just look it up) but if a planet 4.7 times as heavy and 50% bigger than Earth was considered too small/lightweight to be considered a planet I'd seriously consider packing my bags and moving to a real planet like Uranus (to live in an airship of some sort that is, I'm very aware that you can't actually stand on Uranus, thank you!).

      • You can sit on it though.

        In your mother's basement.

        Posting on Slashdot.
      • According to the IAU definition a planet needs to orbit around the Sun. No exoplanet is really a planet. Though the question depends a lot on what it's made of. It needs to be at hydrostatic equilibrium and fairly round (this is easier fluids and gases) and it needs to have cleared it's area.

        Lets say it needs to be about the size of mercury and sweep the question under the rug as frankly a ball of water the size of a basketball, if the only object orbiting a star, would qualify as a planet.

        • But a ball of water the size of a basketball would rapidly boil off into space, so it's not in hydrostatic equilibrium, is it?

    • Re: (Score:2, Informative)

      by Ragzouken (943900)
      It's more to do with the planet clearing its own orbit of debris rather than size, I think.
    • That depends on how generous the discoverer is with their money.
    • anything large enough to clear its immediate orbit and roughly sperical- quite arbitrary as Earth anda few other "planets" havent quite cleared their orbits either.

  • I call it... (Score:4, Funny)

    by spazdor (902907) on Thursday April 10 2008, @03:54PM (#23029578)
    'Pluto.'

  • Bearing in mind... (Score:5, Insightful)

    by localroger (258128) on Thursday April 10 2008, @03:56PM (#23029610) Homepage
    ...from this distance and with this technique, Venus would qualify as "a planet like Earth." It would truly suck to be the person who hiked 50 light-years to find that out.
    • If we can identifying earth sized planets they can be cataloged until resolution improves enough for spectroscopy to be used to identify atmospheric composition.
        • Don't assume that intelligent life could only develop on a planet exactly like ours. Even just considering carbon-based life as we know it, life could still survive just fine [molvray.com] in a higher or lower gravity version of Earth. Lower gravity would likely mean a thinner atmosphere but oceans would still be habitable. Higher gravity would mean life forms couldn't grow as large on land. I don't think either of those would prohibit intelligent life from developing. And that's also assuming intelligent life just

  • The article is wrong (Score:5, Informative)

    by Geoffrey.landis (926948) on Thursday April 10 2008, @04:03PM (#23029680) Homepage
    The article seems to be wrong. Smaller planets have been discovered orbiting pulsars [wikipedia.org]. Check out PSF 1257+12a [extrasolar.net] for a small planet.

    What they mean to say is that this seems to be the lowest mass planet found orbiting a main-sequence star.

    It's also annoying that the press release quotes the radius of the planet (which cannot be measured, and is only an approximation based on guesses at density), when what they actually measured is the mass. Planetary densities vary widely; they have no idea what the radius is.

  • Before we discover such planets so far away, we should figure out a way to travel faster close to the speeds of light - i wouldn't wanna spend 30 precious years on a one leg journey

    • There are two big problems with traveling that fast. The first is shielding. At really high speeds every stray atom becomes a cosmic ray. The second is the amount of energy and reaction mass needed.

      • Actually here are two problems as I see it

        I agree with your shielding, force field would become a must for several reasons like radiation.
        1. long range and real time sensory is a bigger issue. You are seeing things where they use to be, and moving that fast

        Energy is the easy part, we continue to develop nuclear or work on antimatter. The size/mass of it wont matter once it is out of our gravity.

        I think we wont get shielding or long range sensory till after we can create gravity(or anti gravity) with a fli

    • Re: (Score:2, Insightful)

      by hansraj (458504)
      Do you honestly believe that all technology either should develop "all at once" or should follow your chronology? Besides the point of looking deep into the space is not entirely to find a place for humanity to go. Just understanding the universe is a goal worth pursuing. At least that's how some other people view science and fortunately I should say.
      • Understanding is always good. But shouldn't we prioritize the research. The universe is so vast there is always a finite possibility of discovering earth like planets within finite time. When such a possibility already exists, it is worth investing in ways to actually make use of any such discovery.
        • This way we will know where to go when we do figure out to travel to them in a reasonable way. perferable warp speed, or dimension skipping.
      • If you look over the last twenty years in relation to human history (to say nothing of geological time frames) technology has developed all at once. There's a huge, nay exponential effect on technology of having near universal communications and access to knowledge content. If you scrape off the foam from the top of the Internet, there's an aweful lot of beer there. It's nearly instantaneous from that perspective.

  • just goes to show how crazy science is (Score:4, Insightful)

    by jollyreaper (513215) on Thursday April 10 2008, @04:10PM (#23029746)
    I remember watching my Star Trek and seeing them fly their starships right up to star systems because that was the only way to explore them. Shit, I suppose you'd still have to put sats in orbit and probes on the surface to do detailed science but holy shit, detecting planets from lightyears away, even making guesses as to habitability by looking at star type, planetary orbit, even getting spectrographic readings from the atmosphere. I never would have believe it in a book. Yeah, hyperdrives I could buy but not this. Reality is stranger than fiction. Heh, it's just like all of the scifi guys assuming that ambulatory robots would be the easy part and making them think fast and speak well would be the tough part.
  • It doesn't even meet the first qualification for being a planet.
  • ...I'm ok with the orbital period of five days, that can be determined by the wobble the planet imparts to the star as it orbits. My problem is, how do they tell its rotational period?

    Think about this for just a moment. Bright star, probably a hundred timed the diameter of the planet, and many thousands of times more luminous; assuming the planet is rocky (and barren, and a colouration about that of bleached tarmac), it'll have a reflectivity of about 15-20% (also known as albedo). Earth's blue-green marble

  • It's not really confirmed... (Score:5, Informative)

    by Plamadude30k (1271120) on Thursday April 10 2008, @08:29PM (#23031782)
    I (and a group of people) am actually researching this system myself. We observed a transit of GJ436b on March 30, and we're reducing the data now. I'd like to point out, however, this paper is NOT a discovery article. I read it in February (before it was published), and I've got it on my desk right in front of me. Basically, it PREDICTS that there MIGHT be a planet of said radius and mass in an orbit about twice as far out as GJ436b (a transiting hot neptune), but it also says that more study is needed to confirm the existence of this planet. What my study was trying to do was to show that there's a change in GJ436b's orbit caused by this new theoretical planet. So far, things look promising, but we haven't confirmed anything yet.
  • In case you haven't checked the reports, the scientists have not *seen* the object. Nor have they *seen* any of the other objects they so quickly claim are exoplanets.

    If all you know are its mass, or diameter, and perhaps its orbital period that is insufficient information to claim it is a "planet". It should be a very large artificial satellite.

    The astronomers are operating off of an assumption that the universe is dead (and therefore natural). Ooopps, then we probably shouldn't be here... They need to
      • No, not a moon. I am merely saying that when you only know its mass (or diameter) and or perhaps its orbital period, its a leap to go claiming something is a "planet".

        Just FYI, the papers by Lineweaver's groups suggest that ~70% of the "Earths" in our galaxy are older than ours, some of them much much older. That leaves plenty of time for them to have developed the technology to disassemble and reassemble planetary sized masses (indeed if we develop robust nanotechnology in this century we will probably h
      • I don't disagree other than from the perspective that Lineweaver's argument says we are the "young kids on the block". You have physicists scratching their heads left and right trying to explain another observation "dark matter" when that is what you would have lots of if advanced civilizations simply converted their stars to Matrioshka Brains (complex Dyson Shells). But doing so would involve many civilizations far more advanced than we are and the physicists don't want to go there... (lets make up some
          • If it were only my reasoning, I might be more willing to take the easy way out and say all masses orbiting other stars are dead planets. But doing so screams of requiring a good explanation for why we are the first and/or only advanced technological civilization in our galaxy. Without some of those on the table the puzzle seems to be missing missing more than a few pieces.
    • pluto is part of the solar system, it may be a long way out but the sun is still the dominant factor in it's orbit.

All trademarks and copyrights on this page are owned by their respective owners. Comments are owned by the Poster. The Rest © 1997-2009 Geeknet, Inc.