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Captured Comet Becomes Moon of Jupiter 108

An anonymous reader writes 'Jupiter's gravity captured a comet in the mid-20th century, holding it in orbit as a temporary moon for 12 years. The comet, named 147P/Kushida-Muramatsu, is the fifth body known to have been pulled by Jupiter from its orbit around the Sun. The discovery adds to our understanding of how Jupiter interferes with objects from the 'Hilda group,' which are asteroids and comets with orbits related to Jupiter's orbit.'
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Captured Comet Becomes Moon of Jupiter

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  • by R2.0 ( 532027 ) on Monday September 14, 2009 @09:37AM (#29412723)

    The comet's shape was revealed to be rectilinear, with an aspect ratio comprising the squares of the first 3 non-zero positive primes.

    • Re: (Score:2, Funny)

      by LaminatorX ( 410794 )

      My God, it's full of stars.

    • Re: (Score:1, Interesting)

      by Anonymous Coward

      The squares of the first 3 positive integers, you mean.
      1 is NOT a prime number.

      • Re: (Score:3, Insightful)

        by LaminatorX ( 410794 )

        That was not an entirely settled matter when The Sentinel was written.

        • Re: (Score:3, Informative)

          by bcmm ( 768152 )
          You're thinking of the dimensions of the TMA-1 Monolith in 2001: A Space Odyssey. In The Sentinel (which 2001 was very loosely based on), the beacon is not a cuboid and has no such geometrical connection to prime numbers.
      • Re:The comet's shape (Score:5, Informative)

        by R2.0 ( 532027 ) on Monday September 14, 2009 @09:55AM (#29412915)

        From Wikipedia:

        "Primality of one

        The importance of this theorem is one of the reasons for the exclusion of 1 from the set of prime numbers. If 1 were admitted as a prime, the precise statement of the theorem would require additional qualifications, since 3 could then be decomposed in different ways

                3 = 1 3 and 3 = 1 1 1 3 = 13 3.

        Until the 19th century, most mathematicians considered the number 1 a prime, the definition being just that a prime is divisible only by 1 and itself but not requiring a specific number of distinct divisors. There is still a large body of mathematical work that is valid despite labeling 1 a prime, such as the work of Stern and Zeisel. Derrick Norman Lehmer's list of primes up to 10,006,721, reprinted as late as 1956,[4] started with 1 as its first prime.[5] Henri Lebesgue is said to be the last professional mathematician to call 1 prime.[citation needed] The change in label occurred so that the fundamental theorem of arithmetic, as stated, is valid, i.e., "each number has a unique factorization into primes."[6][7] Furthermore, the prime numbers have several properties that the number 1 lacks, such as the relationship of the number to its corresponding value of Euler's totient function or the sum of divisors function.[8]"

        At least I came by it honestly.

    • Re: (Score:2, Informative)

      by maxume ( 22995 )

      non-zero positive primes

      Isn't that somewhat redundant?

      • No, because "non-zero" can be negative too. Although I suppose the end result will be positive regardless...

        • Re: (Score:1, Redundant)

          by clone53421 ( 1310749 )

          I'd say it's doubly redundant. Primes are, by definition, both nonzero and positive.

          Nonzero and positive are only slightly redundant themselves, since mathematics will only occasionally deal with positive and negative zero. Computers may also consider zero to be a positive number, so "nonzero and positive" might not be redundant in computing.

        • by maxume ( 22995 )

          At some level, primes are defined to be positive and non zero (or at least, that is the way I have understood things, but I'm no mathematician, so the 'real' definition may be a good deal more complicated than the simplified one us normal people use).

    • Re: (Score:3, Funny)

      by jollyreaper ( 513215 )

      The comet's shape was revealed to be rectilinear
      Though some thought it a doorway with stars in here
      with an aspect ratio comprising the squares
      of the first 3 non-zero positive primes.
      Burma shave

    • Re: (Score:2, Funny)

      by rattaroaz ( 1491445 )

      The comet's shape was revealed to be rectilinear, with an aspect ratio comprising the squares of the first 3 non-zero positive primes.

      I thought only Uranus was rectalinear.

      • Re: (Score:1, Funny)

        by Anonymous Coward

        No, you're thinking of rectumlinear.

  • But... (Score:5, Funny)

    by njfuzzy ( 734116 ) <ian&ian-x,com> on Monday September 14, 2009 @09:39AM (#29412739) Homepage
    "That's no moon!"
  • Good catch Jupiter (Score:5, Insightful)

    by moon3 ( 1530265 ) on Monday September 14, 2009 @09:49AM (#29412857)
    One can imagine that over billions of years Jupiter helped to clear-out our system from similar thrash pretty well.
    • Re: (Score:3, Funny)

      by navygeek ( 1044768 )
      Jupiter is like VICE Cops on a rampage...
    • by speedtux ( 1307149 ) on Monday September 14, 2009 @10:05AM (#29413011)

      Yes, it did. A planet like Jupiter may actually have been essential for complex life to develop on Earth.

      • Re: (Score:2, Funny)

        by Anonymous Coward

        What an intelligent design to put it there, to dispose of all the garbage.

      • by K. S. Kyosuke ( 729550 ) on Monday September 14, 2009 @10:53AM (#29413615)
        Actually, had there been no Jupiter in our Solar system, the aliens would have probably parked the monolith in the orbit of Iapetus instead of Europa. Europa only made commuting easier for them.
      • See "Rare Earth" by authors Ward and Brownlee.
      • Re: (Score:3, Interesting)

        by Chris Burke ( 6130 )

        Yes, it did. A planet like Jupiter may actually have been essential for complex life to develop on Earth.

        Maybe. However in addition to capturing bodies that could have threatened earth, Jupiter also attracts objects from the Oort Cloud etc. that would not have been any threat to Earth otherwise. The jury is still out on whether Jupiter is actually a net positive.

    • Re: (Score:1, Offtopic)

      by clone53421 ( 1310749 )

      What I want to know is... was a flickering bat logo projected onto the clouds of Jupiter right before this rogue comet was incarcerated?

  • by ciderVisor ( 1318765 ) on Monday September 14, 2009 @10:03AM (#29412989)

    "Whether they ever find life there or not, I think Jupiter should be considered an enemy planet." - Jack Handey

    • Why yes, I am an MS shill - I earned US$10 for this post alone !

      Do they have an affiliate program? I am prepared to prostitute myself. Posting on /. is getting laid for nerds

  • Comment removed (Score:3, Insightful)

    by account_deleted ( 4530225 ) on Monday September 14, 2009 @10:05AM (#29413017)
    Comment removed based on user account deletion
    • by clone53421 ( 1310749 ) on Monday September 14, 2009 @10:14AM (#29413107) Journal

      Yeah, and it's been thrown around the table a few times, but we still haven't figured out what sort of payment Jupiter will accept (or how to get it there). Hiring out gas giants for protection turns out to be less easy than you'd expect.

      • by Tablizer ( 95088 )

        Maybe Jupiter is Mafia. It protects us, but expects some kind of payment. Maybe free planet pr0n? I hear Uranus has a nice...

        • Maybe Jupiter is Mafia. It protects us, but expects some kind of payment. Maybe free planet pr0n? I hear Uranus has a nice...

          Shhh. It's a conspiracy. Remember how Pluto got reclassified as a "dwarf planet"? They did that because Jupiter's got a "little planet" fetish.

      • Re: (Score:3, Interesting)

        Comment removed based on user account deletion
    • Re: (Score:2, Troll)

      by AmigaMMC ( 1103025 )
      NASA should be spending most - if not all - of its budget preparing to avert a comet/asteroid from hitting earth

      They already did: They created Jupiter!

    • by Red Flayer ( 890720 ) on Monday September 14, 2009 @10:23AM (#29413225) Journal

      NASA should be spending most - if not all - of its budget preparing to avert a comet/asteroid from hitting earth.

      With all due respect, I disagree. Yes, some resources should be directed at that problem. But there is so much more that can and should be done by NASA. The Hubble, Chandra, and Spitzer telescopes are a good example.

      But what is the point in surviving if all we are doing is treading water? Sure we could spend billions on monitoring near space for potentially dangerous objects, but IMO we're better off spending those billions on things that can advance technology.

      And in the (very) long run, our currently feeble attempts at space travel may lead to the best defense against catastrophic collisions -- another colonized planet.

      • Sorry, but how is colonizing another planet going to prevent a catastrophic collision?
        • by KeithJM ( 1024071 ) on Monday September 14, 2009 @11:17AM (#29413939) Homepage

          Sorry, but how is colonizing another planet going to prevent a catastrophic collision?

          Imagine when all of what would become the human race lived in one valley in Africa. One particularly harsh winter or dry summer could wipe out the whole species, right? If that happened today it might still be a catastrophe but humanity would go on. If we had self-sufficient colonies on other planets, an asteroid could destroy the earth without killing off humanity.

        • It wouldn't prevent the collision, but it would prevent the catastrophe of eliminating all human life.

        • It won't help prevent a body from hitting the earth.

          What it will do is lessen the relative damage caused by such an impact.

          Instead of wiping out all of humanity, and drastically change the ecosystem humans live in, it will only wipe out part of humanity, and some of the ecosystems we live in.

          You know that old adage about putting all your eggs in one basket (don't do it!) -- we currently have all our eggs in one basket, and it would be nice if we could change that situation.
        • Sorry, but how is colonizing another planet going to prevent a catastrophic collision?

          No need to be sorry, it's a good question. See, the aliens only have the resources to throw biosphere-destroying meteors at one planet, and if we spread to more than one they will save their resources for defense against our inevitable invasion and conquering of their own planets.

          It makes perfect sense once you have all the data. See http://traipse.com/upgrade/index.html [traipse.com] for another idea about averting a catastrophic col

      • Comment removed based on user account deletion
        • Re: (Score:3, Insightful)

          by Sir_Lewk ( 967686 )

          We are the first and only known organism that has the ability to improve the state of it's species. We have the ability to make ourselves great and prosper and you propose we do nothing more than simply survive. Take about underachievement.

    • NASA should be spending most - if not all - of its budget preparing to avert a comet/asteroid from hitting earth.

      No! We should be concentrating on moving our entire solar system away from the galactic core at just under the speed of light. After we clear out all asteroids and comets. Signed, Hindmost

    • NASA should be spending most - if not all - of its budget preparing for the Sun's inevitable expansion into a Red Giant.

      Everything else is moot if we let that happen.

      mmkay, bit of a stretch as an example-- but it seems extremely shortsighted for the National Aeronautics and Space Administration to be solely focused on potentially dangerous bodies. We wouldn't have the capability of deflecting asteroids and comets if it wasn't for the technologies we've developed for exploration.
      • Comment removed based on user account deletion
        • Re: (Score:2, Interesting)

          by yurtinus ( 1590157 )
          Feeding trolls is bad, but perhaps I should clarify regardless:

          NASAs goals and objectives are not solely to protect earth from dangerous rocks. It is a research and exploration agency. I can see that if you're terrified of dangerous space rocks, you'd want to see that mission changed. I simply think it's a bad idea to redirect all of your resources to fend off one threat which has a minuscule year to year statistical likelihood. Sure, don't ignore the threat, but don't give up on all the other exploration
          • Comment removed based on user account deletion
            • Re: (Score:2, Insightful)

              by yurtinus ( 1590157 )
              Except it's not a 1% chance. It's not a 1 in 500 chance. Extinction level impacts are a once in tens of millions of years event. I'm no astronomer, so have no ideas the difficulties involved in finding and tracking all NEOs-- but I do know that the effort involved for that is compounded by any number of objects that don't regularly live in our space. Essentially, you can never be 100% safe. I'm not saying do nothing, it's a mitigation versus aversion discussion. You can mitigate risks substantially where co
    • NASA should be spending most - if not all - of its budget preparing to avert a comet/asteroid from hitting earth.

      Everything else is moot if we let that happen.

      Unfortunately Congress is more concerned with steroids in baseball.
      Sometimes I think we deserve to become extinct.

      If we just gave enough steroids to the baseball players, they could probably hit any threatening meteors, asteroids, or comets out of the solar system, thereby solving both problems.

    • Don't worry, if Jupiter misses one, we've always got the moon as a back up.
    • That's not really NASA's job [nasa.gov]. NASA usually gets criticized for performing commercial or military missions. NASA's job is to do the science: quantify the threat and find good ways to fix it. Their scope might be expanded to a one-off, prototype deflection mission, but a standing "Deflection Corp" would be a millstone about NASA's neck.
      • Comment removed based on user account deletion
        • Busy work week, so I only just checked back... The NEO Program Office FAQ says they work "to detect, track and characterize", and are "responsible for facilitating communications between the astronomical community and the public". Nothing else. Who does the "aversion"? I'm thinking that falls to the "DoD and international agencies" mentioned above. (Sorry about all the quotes.)
  • by Anonymous Coward on Monday September 14, 2009 @10:13AM (#29413087)

    Slashdot
    History for nerds. Stuff that mattered.

    I'll bet if I go back 50 years, I'll find a dupe in the archive.

  • 'Jupiter's gravity captured a comet in the mid-20th century

    Old news?

  • The dinosaurs saved it there for eventual revenge on the mammals. It's like a snowball in the freezer so that you can pound your enemy in the summer, when they least expect it.

  • by wisebabo ( 638845 ) on Monday September 14, 2009 @11:47AM (#29414457) Journal

    The article says that the comet had an orbit around Jupiter of 12 years. Well Jupiter has an orbital period around the sun of almost exactly 12 years also. Does this mean that the comet was in orbit around Jupiter or that it was merely in an orbit that was very similar to Jupiter's (in relation to the sun).

    I believe that there is a NEO that basically does the same thing around earth. It travels in an orbit around the sun just slightly different from the earth so that sometimes it is in front of the earth on it's path and sometimes it is behind. From our perspective it makes a complex lissajous (spelling?) track. But I seem to remember it is definitely NOT "orbiting" the earth.

    The article doesn't specifically state whether or not the comet is gravitationally bound to Jupiter which I guess is the definition of "orbiting" (I'm not a professional astronomer). Even if it was orbiting Jupiter, with a period of 12 years it was very loosely bound. In any case, how was it brought into Jupiter's proximity? How did it get ejected? Where is it now?

    • RTFA!

      "between 1949 and 1961 two full revolutions around Jupiter were completed" (by the comet in question, around Jupiter)

      Two revolutions is not much. It's an orbit, but not a steady orbit. Shoemaker-Levy 9 did 12 orbits in 50 years, a little bit more stable, but alas, it crashed into the planet.

    • Does this mean that the comet was in orbit around Jupiter or that it was merely in an orbit that was very similar to Jupiter's (in relation to the sun).

      The astronomer in the article said that the comet was in orbit around Jupiter -- ergo moon, not simply an object in a similar orbit around the sun.

    • by Tablizer ( 95088 )

      Jupiter has much less mass than the sun such that it's possible to have the same orbital period as Jupiter has around the sun, yet still be relatively close to Jupiter. A 12-year orbit around a small object is usually closer to the parent than a 12-year orbit around a large object.

      However, at that far out, the comet risks being affected by other planets and bodies, such as Saturn. It's roughly comparable to sticking your head too far out of the car window: you risk getting womped about another car.

  • I never really understood the whole "Hot Ice" thing (former jewel thief, maybe?) but Hilda was awesome. Pity she had to buy it early on in the series so Gene could be the star.

  • by jove, another moon!

  • I thought the "Jupiter Shield" myth was pretty much busted.

  • And I just bought the night sky atlas...'DOH'

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