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NASA Space

NASA's Hubble Discovers Another Moon Around Pluto 208

thebchuckster writes "Astronomers using the Hubble Space Telescope discovered a fourth moon orbiting the icy dwarf planet Pluto. The tiny, new satellite – temporarily designated P4 — was uncovered in a Hubble survey searching for rings around the dwarf planet. The new moon is the smallest discovered around Pluto. It has an estimated diameter of 8 to 21 miles (13 to 34 km). By comparison, Charon, Pluto's largest moon, is 648 miles (1,043 km) across, and the other moons, Nix and Hydra, are in the range of 20 to 70 miles in diameter (32 to 113 km)."
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NASA's Hubble Discovers Another Moon Around Pluto

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  • Poor Pluto, they can take away your planetary designation but you will always have your moons!

    As for Hubble, I am quite happy with its continued usefulness and success. Hopefully it never loses its funding (at least not until there is a suitable replacement).

    • Re:Pluto's Moons (Score:4, Insightful)

      by Ellis D. Tripp ( 755736 ) on Wednesday July 20, 2011 @11:54AM (#36825280) Homepage

      Hubble will eventually degrade in performance just as it has in the past. Gyros and batteries wear out, electronics get glitchy, etc.

      Unfortunately, when it starts to happen again, there won't be anything we can do about it. Without the shuttle, another service mission is impossible. And with Hubble's successor (JWST) hanging by a fraying budgetary thread, there likely will be no replacing it with an improved telescope, either.

      We as a country have given up on science, unless it makes immediate profits for megacorporations or helps the military kill people more efficiently in foreign lands.

      • Re:Pluto's Moons (Score:5, Insightful)

        by the gnat ( 153162 ) on Wednesday July 20, 2011 @12:09PM (#36825498)

        Unfortunately, when it starts to happen again, there won't be anything we can do about it. Without the shuttle, another service mission is impossible. And with Hubble's successor (JWST) hanging by a fraying budgetary thread, there likely will be no replacing it with an improved telescope, either.

        This has been repeated a number of times, but launching an entirely new Hubble into high orbit (without a shuttle, that is) would be substantially cheaper than maintaining the shuttle program in order to service the existing scope. I hope JWST pulls through, but I don't think NASA should get a blank check from the taxpayers.

        We as a country have given up on science, unless it makes immediate profits for megacorporations or helps the military kill people more efficiently in foreign lands.

        I'm not a fan of our budget priorities for the last decade, but I can understand why Congress is viewing JWST skeptically. The telescope isn't even supposed to launch until 2017 at the earliest and it's already billions of dollars over budget. Sure, this is a fraction of what we're flushing down the toilet in futile wars, but we're already stuck in those, and they're much more difficult to pull out of than a project that's still in the planning stages.

        Except for servicing Hubble - a dubious justification - the shuttle was a terribly inefficient use of money for the science that came out of the program. As far as scientific funding in general is concerned, NASA continues to do great work with remote probes and will be sending another rover to Mars soon. The NIH and NSF managed to avoid major funding cuts in a year when most federal agencies got hit hard, and the DOE Office of Science, which was slated for a huge cut, also survived mostly intact. Speaking as a scientist involved with many of these agencies, I'm thrilled with the outcome.

      • by vlm ( 69642 )

        We as a country have given up on science, unless it makes immediate profits for megacorporations

        I'm not thinking Hubble was manufactured by schoolchildren or launched by a volunteer group.

        That's the mystifying part. You'd think there's just as much room for corruption in the aerospace contracting field as the banking field, but apparently fraud is easier in the banking industry. Since they (as in the big bankers) are not going to let us fix the banking system, the solution would seem to be, make the aerospace industry as corrupt, or more corrupt, than the banking industry.

        I'm sure we could set up so

      • We as a country have given up on science, unless it makes immediate profits for megacorporations or helps the military kill people more efficiently in foreign lands.

        What's more disappointing is that the other industrialized countries haven't taken this torch and run with it. Europe has at least 50% more population than the USA, and a larger economy (and it appears, stronger, despite the problems in Greece). While obviously no one country there can match the US in size and economic power, combined they eas

        • by rgviza ( 1303161 )
          The USA economy is the largest of any single country in the world. The entire EU beat us very narrowly with 1.5x the number of people.

          Remember this when people start talking about "lazy Americans". We're producing nearly as much as 1.5x the number of Europeans are.

          US citizens are quick to claim that the US isn't this, or the US isn't that. Fact of the matter is we are still the shit.

          We have the highest GDP of any country, we have the highest standard of living, and have the highest rate of scientific advanc
          • we have the highest standard of living,

            Wrong. Sweden, Norway, and Switzerland consistently lead the standard-of-living rankings worldwide. USA is way down on the list. Having the "highest standard of living" doesn't mean your richest people live the most opulent lifestyles, it means your average people live the safest, most comfortable, and most healthy lifestyles. If you want to compare the rich peoples' lifestyles, then places like Mexico would rank high on the list, since the world's richest man, Carl

          • Those "jobs a trained monkey can do" will always orders of magnitude more plentiful than the jobs that require a college education. This means that the pay rates going to those workers will do far more to the economy than the budgets of a few engineers and scientists. This attitude that pay rate should be mostly determined by level of education will eventually destroy any economy that buys into it. I don't care how much a country develops, no population can be sustained on primarily higher education jobs.
      • "Gyros and batteries wear out"

        That certainly explains the discomfort I felt last night after eating a week-old Greek pita sandwich and a couple of AAs I found in my desk drawer.

  • it's just an icy something.
  • by Anonymous Coward on Wednesday July 20, 2011 @11:41AM (#36825088)

    Four moons means it gets to be called a planet.

    • by alta ( 1263 )

      not sure who modded you down, but I was thinking the same thing.

      I spent my entire childhood thinking pluto was a planet. To me it will always be a planet. Even my 9yo was originally taught it was a planet. Where's the love? Seriously, after 76 years, NOW you're going to choose to call it a 'dwarf planet'? I think not.

      If you have enough gravity to have something orbiting you, then you get to be a planet.

      There's got to be an 'in soviet russia' joke here, I'm just not sure what it is yet.

      • by sconeu ( 64226 )

        NOW you're going to choose to call it a 'dwarf planet'?

        Please. Pluto prefers the term "Gravitationally Challenged Planet"

        • Please. Pluto prefers the term "Gravitationally Challenged Planet"

          If Pluto wants to make something of it, it knows where to find us. I dare it to come complain about what we call it...

          So, if Pluto isn't a planet, then what orbits it can't be moons, right? Moonoids? Moonsters? Moonites? Moonies? Moonenites?

      • by rgviza ( 1303161 )
        What about Venus, which has no moons, but is similar in mass, bulk composition and size to the earth?

        Satellites (or lack thereof) don't make or break "planet" status.
        • by alta ( 1263 )

          See my rule # 4, it was specifically designed for Mercury and Venus, who are both Larger than pluto, yet have no natural orbiting rock.

      • by ari_j ( 90255 )
        While the official definition that made Pluto no longer a planet does not include this, I know I have seen various discussions justifying Pluto's dwarf planet status by pointing out that the center of mass for Pluto and its natural satellites is outside the solid part of Pluto itself. So what I have wondered today with this article is this: Does the new moon change that fact and move the center of mass back to Pluto proper?
    • There's tons of tiny asteroids with their own, even smaller, moons. Are we going to call those planets too? Do we need to have schoolchildren remember the names of hundreds of moon-bearing asteroids, I mean planets?

      • by vlm ( 69642 )

        Do we need to have schoolchildren remember the names of hundreds of moon-bearing asteroids, I mean planets?

        We're already at 53 planets. Whats one more?

        http://en.wikipedia.org/wiki/List_of_extrasolar_planets [wikipedia.org]

        The good news is the names are pretty easy. Whats the planet orbiting between Kepler-11 B and Kepler-11 D? Oh let me guess it's Kepler-11 C.

        • The good news is the names are pretty easy. Whats the planet orbiting between Kepler-11 B and Kepler-11 D? Oh let me guess it's Kepler-11 C.

          What happens when they find a new planet between them? Rename everything farther away, leading to questions like "did you mean the object named Kepler-11 C before [date], or the object named that after [date]?"

          Interstate exit numbers suffered this same issue every time a new exit was built, by the way, which is why they all got renumbered after the corresponding mile ma

          • I thought there were still some stupid states that hadn't done that, or are you saying the last holdouts (I'm thinking PA was one) finally changing their exit numbering?

            • I thought there were still some stupid states that hadn't done that, or are you saying the last holdouts (I'm thinking PA was one) finally changing their exit numbering?

              They haven't changed them here in CT or in nearby NY yet. There are, however gaps in the numbers sometimes...not sure if it's because the exits were removed, planned but never made, or someone didn't know how to count. For example, the first exit on I-95 in CT is exit 2.

      • by arth1 ( 260657 )

        Let's be consistent:
        Only satellites that have been pulled into a spherical shape by their mass and have cleared their orbit around the planet should be called "moons". The rest are obviously "dwarf moons".

        As for what we should call a satellite that orbits a satellite, I vote for "Zappa".

    • In this time of austerity the funding for the agency that supported de-listing Pluto as a planet probably needs a second look.
    • by arth1 ( 260657 )

      Four moons means it gets to be called a planet.

      Surely that depends on the number of wolves.

  • Get over it. We have a better understanding of the Cosmos now without blurry images from a couple pieces of polished glass. Think of it as an advancement in our scientific horizons.

  • All this talk about mooning has me wistful for my wild youth.

  • What I've always found peculiar regarding the definition used to demote Pluto is that by that very definition, Neptune should be a non-planet as well, seeing as it hasn't "cleared" it's orbital path either.
    • If you calculate the ratio of the mass of the object to the mass of all the other objects in the same orbit, there is a vast difference between the planets and the dwarf planets. The eight planets have ratios on the order of 10^4 through 10^6, meaning they are much, much more massive than everything else in their orbit combined. The dwarf planets, including Pluto, all have ratios less than one.

      • But ratios aren't in the definition. From the wikipedia article: "...a planet is a body that orbits the Sun, is massive enough for its own gravity to make it round, and has 'cleared its neighbourhood' of smaller objects around its orbit." These three criteria define a planet and Pluto definitely meets the first two. As for the last, Pluto's perihelion is inside Neptune's orbit, thus (in my humble opinion) still clutters Neptune's orbital neighborhood. I think the definition should have been chosen so a
        • "Cleared the neigbourhood" has a specific meaning. It means that the object has become gravitationally dominant, and there are no other bodies of comparable size other than its own satellites or those otherwise under its gravitational influence. Pluto is in a resonant orbit with Neptune. In other words, Pluto falls into the "those otherwise under its gravitational influence" category. If you want an absolutely clear orbit, the even Jupiter fails. Basically, every planet has co-orbitting asteroids.
      • Thank you! This is the key point that somehow never gets discussed. And of course I never have mod points when I need them.

  • Poor Pluto, it orbits around the Sun and has four Moons of its own, and yet they still insist it's not a planet.
  • Mass relay... (Score:3, Insightful)

    by alendit ( 1454311 ) on Wednesday July 20, 2011 @12:35PM (#36825856)

    I thought there'd be more Mass Effect jokes. Jeeze, people, it's 2011, get over Star Wars!

  • by mdf356 ( 774923 ) <mdf356@gmai[ ]om ['l.c' in gap]> on Wednesday July 20, 2011 @01:23PM (#36826502) Homepage

    Using Pluto's density of 2.03 g/cm^3, I compute (at 21 mile diameter) the moon is 4.2e16 kg.

    With a 4.2e16 kg mass and 1.7e4 m radius, I compute an escape velocity of 18 m/s, or 40 miles per hour.

    So I suspect you could jump really hard and not come back down, assuming I didn't misplace a decimal point.

  • vampire movie where the vampires have feelings and stuff... have they released the sequel?

  • by orn ( 34773 ) on Wednesday July 20, 2011 @02:12PM (#36827004)

    Earth needs more moons!

    We should get some.

  • How many moons does it take before something becomes a planet?

    [Your mom]

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