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Space Science

North Star May Be Wasting Away 129

sciencehabit writes "The North Star, a celestial beacon to navigators for centuries, may be slowly shrinking, according to a new analysis of more than 160 years of observations. The data suggest that the familiar fixture in the northern sky is shedding an Earth's mass worth of gas each year."
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North Star May Be Wasting Away

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  • Oh my god! (Score:4, Funny)

    by Anonymous Coward on Friday January 27, 2012 @05:40PM (#38845937)

    Polaris must be losing nearly the equivalent of Earth's mass—or a little under a millionth of its own mass—each year,

    In a little over a million years, we won't be able to use that particular star to navigate any more. IT'LL BE CHAOS!

    • Re: (Score:3, Informative)

      by GodInHell ( 258915 )
      Not to take you too seriously -- but it would probably shrink to the point where it became impossible to see the north star long before that.

      We do however have wonderful things called "Com-pass-es" that work similarly (even inside and in daytime).

      -GiH
      • by SpryGuy ( 206254 ) on Friday January 27, 2012 @05:56PM (#38846113)

        Well, except that over that same time period, we'll be experiencing a reversal of the poles, and the accompaning period of magnetic flux that would make magnetic compasses rather useless.

      • Relativity Speaking (Score:5, Informative)

        by Niscenus ( 267969 ) <.moc.ten-ze. .ta. .nezcire.> on Friday January 27, 2012 @09:54PM (#38847639) Homepage Journal

        A solar mass is over 300,000 Earths, and Polaris is atleast 7 solar masses, adjusting for the most conservative of all estimates. It's apparent magnitude is about 1.9, while the magnitude of drop off (nolonger visible to the human eye) is defined at 7 (with 6 being relatively hard except under good conditions).

        Setting aside the nuclear chemistry that will occur in the meantime (which tends to increase brightness), that Polaris is, in fact, multiple stars and the overall reduction of radiative and mass pressure that will be reducing the production/consumption rate*, I would posit even losing half of its mass, it would likely still be visible in 2000 years, which means the Northern Star will have since switched to Gamma Cephei.

        So, no big loss here. Personally, I, for one, welcome our new Alrainian OverStar.

        ****
        *You know what, I'm actually going to do these in the coming weeks. This is sound like a fun problem, even though I do a lot more in theoretical particle physics than cosmology.

    • Re:Oh my god! (Score:5, Informative)

      by Hatta ( 162192 ) on Friday January 27, 2012 @05:43PM (#38845963) Journal

      The Earth precesses once ever 26000 years. In 13000 years north will be pointed towards Vega.

      • by Anonymous Coward on Friday January 27, 2012 @05:44PM (#38845987)
        Vega is a fucking space ghetto. I don't want to point to that part of the celestial neighborhood.
        • by sconeu ( 64226 )

          I thought that was where the Mother Thing [wikipedia.org] was from? Doesn't sound like a ghetto... Wormface and company were from the ghetto.

          • by jamstar7 ( 694492 ) on Friday January 27, 2012 @06:46PM (#38846577)

            Vega is a fucking space ghetto. I don't want to point to that part of the celestial neighborhood.

            I thought that was where the Mother Thing was from? Doesn't sound like a ghetto... Wormface and company were from the ghetto.

            Problem is, what comes from Vega are Vegans. If they invade, no more leather, no more steaks. We'll be reduced to eating vegetables and tofu forever and ever and ever, amen

            Course, the upside is, we'll produce plenty of methane, so it might help with the energy crunch, though I kinda doubt it'll be comfortable walking around with a gas pipe up my ass. Maybe that's why the aliens are so into anal probing...

          • Wow, I only recently started delving into Sci-Fi stories. Never heard of this one but it sounds cool. Thanks for the post! (The most recent one I read is " Machines That Think: The Best Science Fiction Stories About Robots and Computers" A pretty good collection.)
            • Wow, I only recently started delving into Sci-Fi stories. Never heard of this one but it sounds cool. Thanks for the post! (The most recent one I read is "
              Machines That Think: The Best Science Fiction Stories About Robots and Computers" A pretty good collection.)

              Have Space Suit—Will Travel is OK, but a bit strange, like many of Heinlein's novels. If you haven't read anything else by him I would rather recommend Starship Troopers or The Moon is a Harsh Mistress for starters.

              I haven't read the collection you mention, but I have read about half of the stories therein, most are good ones. While I'm here I can give you some completely unsolicited pointers: Stephen Baxter (Evolution, and Manifold books, which explore fundamental concepts of physics and cosmology),

              • by unitron ( 5733 )

                Clarke's short stories should not be overlooked.

                I particularly recommend "I Remember Babylon".

              • by matfud ( 464184 )

                Try Ken Macleod or Alister Renolds. Both are excelant authours. I like Ian M banks too. Asimov is cool too. Try Edgar Rice Buroughs if you want a taste of the past. John Carter of mars.

                • by matfud ( 464184 )

                  The Stars My Destination (Alfred Bester) although I think it was renamed Tiger Tiger. There are lots to read. Some are shit. Many are good.

              • by dwye ( 1127395 )

                It's a daunting amount of SF out there, and a lot of it is crap,

                Would you say, perhaps, 90%? (aka, Sturgeon's Law, after famed SF writer Theodore Sturgeon who declared, on a talk show, that 90% of EVERYTHING is crap, after the other guest, an English professor, claimed that 90% of [then-]current [ie, late 50's] SciFi was crap)

                Seriously, a lot of the crap can be good, too, if approached in the right mood. E. E. "Doc" Smith produced some utterly laughable crap that is fun to read, just as Plan 9 From Outer Space (generally acclaimed as the Worst Movie Ever) is fun to wat

        • What happens at Vega stays at Vega.

      • Re:Oh my god! (Score:5, Informative)

        by Anonymous Coward on Friday January 27, 2012 @06:43PM (#38846555)

        You're right

        Karma whoring:
        "...Gamma Cephei (also known as Alrai, situated 45 light-years away) will become closer to the northern celestial pole than Polaris around AD 3000. Iota Cephei will become the pole star some time around AD 5200.

        First-magnitude Deneb will be within 5 of the North Pole in AD 10000.

        The brilliant Vega in the constellation Lyra is often touted as the best North Star (it fulfilled that role around 12000 BC and will do so again around the year AD 14000). However, it never comes closer than 5 to the pole.

        When Polaris becomes the North Star again around 27800 AD, due to its proper motion it then will be farther away from the pole than it is now, while in 23600 BC it came closer to the pole.

        In 3000 BC the faint star Thuban in the constellation Draco was the North Star. At magnitude 3.67 (fourth magnitude) it is only one-fifth as bright as Polaris, and today it is invisible in light-polluted urban skies..."

        -Wikipedia

        • slashdot ate your degree signs (some geek site huh?)

          also of interest is that Deneb is presently the North Pole star of Mars.
      • The Earth precesses once ever 26000 years. In 13000 years north will be pointed towards Vega.

        For fun I cranked up Stellarium to check the relative positions of Polaris and Vega. Does anyone know a way to make Stellarium draw a trail for stars like it does with planets? I turned up the time rate to whiz through thousands of years per second and can sort of make out the the path of Polaris with respect to the North pole due to precession, but it would be nice to have it trace out the path.

        BTW, Stellarium stops at the year 99999. That seems like an odd limit.

      • But Polaris is the BEST pole star! Of all the stars close to the polar precession circle, Polaris is the brightest star that is very close to the actual polar axis at the point of closest approach. There are only 4 or 5 naked eye stars that are closer to the precession circle, but they are a good bit dimmer than Polaris. The only one brighter is Vega, but it is never closer than about 5 degrees.

        Polaris is currently getting closer and closer to the pole. It will reach its closest apparent declination on 24 M

    • Re:Oh my god! (Score:5, Insightful)

      by ackthpt ( 218170 ) on Friday January 27, 2012 @05:44PM (#38845995) Homepage Journal

      Polaris must be losing nearly the equivalent of Earth's mass—or a little under a millionth of its own mass—each year,

      In a little over a million years, we won't be able to use that particular star to navigate any more. IT'LL BE CHAOS!

      It's more likely to collapse and blow off gas in a nebula before then, but agree, it's very hard to use nebulas as navigational aids during the daylight hours and tricky enough at night.

      • But I use nebulas to navigate in Freelancer all the time. They're so bright and colorful you can't miss them...Oh wait.
    • I call dibs on the world wide contract to fix the P1M bug. Don't wait till the last second, pay me now.

    • by ceoyoyo ( 59147 )

      Don't worry, in a couple thousand years we'll have a new north star.

  • by ackthpt ( 218170 )

    That's not exactly a lot. I'm sure our own dear Sun is losing that much mass every year and you still see 5 Billion on its birthday card.

    Slow astrophysical news day, I guess.

    • by icebike ( 68054 ) * on Friday January 27, 2012 @05:57PM (#38846131)

      Mass of the sun is 330,000 times the mass of earth.

      So if it were losing an Earth-Mass yearly it would have had to be 7 times as massive as today at the beginning of the Pleistocene, and would only have a life expectancy of about 330,001 years left.

      The Sun appears to have been active for 4.6 billion years and has enough fuel to go on for another Five billion years or so. [solarviews.com].

      So I think you may have lost a few digits (in the exponents) when making your calculations.

      • by ackthpt ( 218170 ) on Friday January 27, 2012 @06:04PM (#38846185) Homepage Journal

        Polaris is listed, at least in Wikipedia, at 7.54 solar masses. Also, it is a ternary system: one large star, a smaller star and a white dwarf.

        • by icebike ( 68054 ) *

          How is that germane to the GPs post?

          • Re: (Score:2, Insightful)

            by Anonymous Coward

            It goes to credibility, your honour. FFS, he presents facts and you jump on him whilst idiot anons get +whatever insightful/informative.

            Go suck on a lemon, will ya?

          • Among other things, it shows an explaination for the mass lossage. The mass might be feeding the smaller star or the white dwarf.
            • by maugle ( 1369813 )

              Among other things, it shows an explaination for the mass lossage. The mass might be feeding the smaller star or the white dwarf.

              Ooh, if it's sending matter onto a white dwarf, we can hope to see an awesome Type 1a supernova in that part of the sky sooner or later.

            • by icebike ( 68054 ) *

              While that's true, it has no bearing on THIS particular sub-thread where the claim was made the OUR Sun was losing an Earth's Mass every year, when such could not be the case.

              I don't deny the facts of the post, just the odd placement of the reply. I wonder if the post [slashdot.org] was misplaced?

      • by Quirkz ( 1206400 )
        Thanks for running the numbers. My initial guesses would also have been off by a couple of orders of magnitude. I knew an Earth's mass was pretty insignificant compared to the sun, but 330,000 years go by pretty quickly in galactic standards.
    • The star grows dimmer and brighter over a roughly 4-day cycle, and the team studied variation in the length of that cycle. ...
      Even that 4-day pulsation isn't constant: In 1844, it was about 12 minutes slower than it is now.

  • Pivot point (Score:5, Funny)

    by Lev13than ( 581686 ) on Friday January 27, 2012 @05:43PM (#38845979) Homepage

    It's probably losing all that mass due to heat from friction. It must be under tremendous pressure, seeing as how the entire night sky pivots on that single point. Long-term this will have huge consequences - when the North Star finally wears through completely the entire universe will ricochet off into nothingness like a spinning top.

  • Thank God! (Score:4, Funny)

    by johnvile ( 2560845 ) on Friday January 27, 2012 @05:51PM (#38846069)
    Thank God its not shedding the amount of gas a politician evacuates each year. It would be barley visible.
  • by GauteL ( 29207 ) on Friday January 27, 2012 @06:03PM (#38846177)

    After decades of overselling the North Star, is there any wonder there's so little of it left?

    • by ackthpt ( 218170 )

      After decades of overselling the North Star, is there any wonder there's so little of it left?

      It'll be replaced by Mark Zuckerberg, so not to worry. He's a major star on Wall Street right now.

  • that's going to suck when all our compasses stop working.

  • North Star [wikipedia.org] has been gone for a couple decades now.
  • by Kenja ( 541830 ) on Friday January 27, 2012 @06:15PM (#38846305)
    Does this mean victory for the Southern Cross fighting style? Or am I just too much of a nerd so no one will understand the reference?
    • by vadim_t ( 324782 )

      Nope! I was just wondering if somebody would make a Fist of the North Star joke and what it would be.

      I was trying to come up with something, but wasn't getting any decent ideas.

    • No, my brain went to about the same place as yours. I was a bit surprised that no one joked about it sooner.

  • too much fiber?
  • by Anonymous Coward

    ...make our own star in the sky.

    But really, it could be done.
    There is a semi-stable orbit up there that isn't too large that it couldn't replace it
    All it needs to be is a huge lens and some magical arrangement of mirrors to allow pretty much omni-directional capture of sunlight with no moving parts, but semi-directional output down towards Earth.
    You COULD have moving parts, but it would be more complicated than it need be. All it needs is some fuel and corrective orbit systems so it doesn't break away and

  • The data suggest that the familiar fixture in the northern sky is shedding an Earth's mass worth of gas each year.

    Sounds like my Uncle Fred...

  • just forward all AOL disks and discount mortgage mailers to it.

  • by wbr1 ( 2538558 ) on Friday January 27, 2012 @08:04PM (#38847091)
    For celestial navigation after it has waned away, you can use the new spiffy Dark Matter Detector 5000 (Copyright Garmin). It points whichever way the scientific wind is blowing.
  • ...then this would surely take the prize.

    Stars convert matter to energy in the form of electromagnetic radiation as a result of nuclear fusion reactions in the core. Ergo, they shed mass - our own Sun sheds mass at the rate of some 4.2 million tonnes per second (citation [stanford.edu]). This converts to pure energy, incident at Earths equator at around 1000W/m^-2.

    But don't worry, if the iron cycle weren't endothermic then the Sun would be good for another 600 billion years or so...

  • Full of Gas and spewing on for years . . .

    Explains so much about Star Trek VI

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