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Space Science

Does Famous Exoplanet 'Fomalhaut b' Really Exist? 40

astroengine writes "The first exoplanet ever to be directly imaged by the Hubble space telescope may not exist. In 2008, the world was in awe of the famous 'Eye of Sauron' image of the star Fomalhaut's dusty ring — plus a slowly moving object that was identified as Fomalhaut b, a gas giant world approximately three times the mass of Jupiter. However, due to a strange orbital misstep detected between 2008 and 2009 photographs, the validity of Fomalhaut b's detection is being questioned, generating some controversy in the exoplanet community."
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Does Famous Exoplanet 'Fomalhaut b' Really Exist?

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  • This article is really making me question everything.

    • Somone must have destroyed the ring after all. FRODO LIVES!
      • If Frodo still lives then he must be really really really old by now, which is the best evidence available that no one has destroyed the ring and he still has it.
  • by Anonymous Coward on Monday September 26, 2011 @05:31PM (#37520428)

    First Pluto, now Fomalhaut b. Before long we'll find the Earth isn't really a planet either. (Maybe a gigantic computer run by mice or something).

    • Look, if you really wanted to find out you'd go check out Alpha Centauri. Why you lot won't take a interest in local affairs is beyond me.

  • It's really quite simple: We just need to go out there and have a look.
    • by Hentes ( 2461350 )
      The problem is that the planet (if it is) is moving very slow so they have to wait years between the looks to see the motion.
      • Re: (Score:3, Informative)

        by Synerg1y ( 2169962 )

        The further out the planet, and the bigger the star all factor into increasing the orbit time, so considering this planet is 3x the size of our biggest one (Jupiter) and that has an orbit of about 11 years (the size of Jupiter has nothing to do w/ orbit mostly), it might be a while before we can confirm this, possibly even a century.

        • To maintain a stable orbit at the same distance from a more massive object would mean moving faster, not slower, right?
          • by Toonol ( 1057698 )
            Right. The further out the slower the orbit, and the bigger the star the faster the orbit. If I remember right, the orbital period is proportional to the square of the orbital radius, but inversely linear to the star's mass.

            Or, if the sun's mass doubled, our year would be halved if we stayed at the same distance. If our orbital radius doubled, our year would increase in length by four times.

            I should probably check that before I post to slashdot, because they'll be cruel if I remember incorrectly.
            • I should probably check that before I post to slashdot, because they'll be cruel if I remember incorrectly. But, eh. I'll take my chances.

              You lose! For exoplanets of mass insignificant compared to its parent star, the relation is
              M(star) x Period^2 = Distance^3

              So if the mass of the star were doubled, the period would decrease by a factor of 0.7071. And if the orbital radius doubled, the period would increase by a factor of 2.828.

              On the plus side, that would alleviate the global warming situation, a

          • The force that would cause that would be gravity I believe, you might be right, but density is what controls the gravity / pull of a star I believe. I was thinking more along the lines of a radius and the increase in circumference from an increase in diameter via the pD formula. I couldn't find definitive answer either way though, I'm assuming they are independent of each other and is based more on the density of the star rather than size.

            • by Lore17 ( 1318959 )

              Gravity is proportional to mass, not density. The density of a star doesn't really matter; if you are a distance away greater than the stars radius you will feel a force as if all the stars mass were concentrated at the center.

      • Maybe it's made of neutrinos and moving so fast that it looks like it's not moving fast! ...like wheels on a car moving at 61 revs per second with a 60 frames per second capture.

    • I was there just last month. It's a big ugly planet. Hell, they don't even have a Starbucks!
  • by Anonymous Coward

    There is an exoplanet community?

  • by JoshuaZ ( 1134087 ) on Monday September 26, 2011 @06:09PM (#37520776) Homepage
    According to TFA, the central problem is that the claimed planet seems to have an orbit which goes into the dusk disk around the star. But if this happens regularly, the disk should have been disrupted. The planet is also much brighter than one would expect for a planet in that position. If this isn't a planet it isn't clear what it is. There does seem to be something there. This could be some sort of artifact of the imaging methods but given the fact that it has been imaged with multiple instruments this seems extremely unlikely. So if this turns out not to be a planet we may be looking at some neat astronomical phenomenon not previously seen. Or it could be a bunch of unusually shiny dust. Hard to tell at this point. This is the sort of thing where the James Webb Telescope could be quite helpful. As of the last update it looks like James Webb is back on. But given how the current Congress acts, it could easily move to being canceled again.
  • by tragedy ( 27079 ) on Monday September 26, 2011 @06:16PM (#37520858)

    This article seems to be about a grudge match between Paul Kalas, who was the lead in the discovery of this planet and Ray Jayawardhana, another astronomer who seems to want to be the first to have directly imaged an exoplanet. Since Kalas came first, Jayawardhana's only option seems to be to discredit the earlier discovery. One of his arguments is that Fomalhaut B wasn't really directly imaged since it probably has rings (accounting for its brightness) and so the rings were what was imaged and not the planet. The chief argument seems to be that the third picture taken of it doesn't match the expected orbit from the previous 2 pictures. The previous 2 pictures, however, were taken with an instrument that broke before the third picture was taken, so the accuracy of the third picture is in doubt. In any case, no-one seems to be doubting that it's something really, really big, but nowhere near big enough to be a star, that's been imaged in another star system. So, if it's not an exoplanet, it's still something extraordinary.

    • Exactly right. To quote TFA:

      Kalas said that, to be scrupulously fair, Schneider should also mention that there are doubts associated with 1RXJ1609, a planet imaged directly at infrared wavelengths that Jayawardhana co-discovered and announced in 2008

      Kalas notes that he coined the term 'planet mania' in a 1998 article in Science, in which he criticized Jayawardhana for making inflated claims about observing planets

      [Christian] Marois says it's far more likely that Kalas is adjusting his analysis to the different instrument on Hubble, and that the original orbit will hold. If anything, he says, the fact that Kalas spotted Fomalhuat b at all in 2010 is "another confirmation that this thing is real".

      Jean Schneider, an astronomer at the Paris Observatory who maintains the exoplanet.eu database, says that Fomalhaut b will remain on the list.

      So Jayawardhana is the only guy who seems to be raising these 'doubts'?

  • That's no planet. It's a space station.

    • Damn you! You stole my joke. And I thought it was so original. /me shakes tiny fist in impotent fury

  • Given the difficulties in merely detecting, much less observing, exoplanets, and the fact that we haven't been doing this for very long and the technologies are new, the only surprise that there aren't more undecided cases like this.

  • According to Jayawardhana, this deviation may be the final proof that kicks Fomalhaut b's existence into touch.

    Kicks into what? What is this supposed to mean? Does this support the planet exists or not support its existence? No I'm not going to go looking for the meaning of some crazy idiom--I could not care less to be frank.

    Bloody journalists. I swear the reliance of democratic society on these people verges on lunacy.

Disks travel in packs.