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Space Science

Star Rips Exoplanet To Shreds With X-Rays 62

Posted by samzenpus
from the you-always-hurt-the-ones-you-love dept.
astroengine writes "Some relationships are doomed from the beginning, and the same can be said of some planetary systems. In the case of the star CoRoT-2a, some 880 light-years from Earth, it is quite literally ripping its orbiting exoplanet to shreds. Five million tons of material per second is being stripped from the closely orbiting world CoRoT-2b by powerful stellar X-rays. But it's OK, the destructive nature of this planetary system is mutual; CoRoT-2b's orbit is likely maintaining the high spin rate of the star, boosting magnetic activity, thus boosting the X-ray output."
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Star Rips Exoplanet To Shreds With X-Rays

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  • I heard (Score:5, Funny)

    by Dunbal (464142) * on Wednesday September 14, 2011 @04:33PM (#37403774)
    There's a rumor going around that the Department of Homeland Security has ordered 10 of these, for the 10 busiest airports.
  • But it's OK, the destructive nature of this planetary system is mutual; CoRoT-2b's orbit is likely maintaining the high spin rate of the star, boosting magnetic activity, thus boosting the X-ray output.

    That's not mutual destruction. Mutual destruction would be if the planet were destroying the star at the same time.

    • by cforciea (1926392)
      I think the idea is that forcing the star to emit a larger number of highly energetic x-rays is likely costing the star energy, which will lead to it dying somewhat earlier. By some metrics, that would count as damage.
      • TFA more accurately uses "negative reinforcement" rather than mutually destructive.

        • by ceoyoyo (59147)

          Negative reinforcement is even less accurate. Negative reinforcement is a training strategy that involves withholding a reward or removing something pleasurable.

    • by walkerp1 (523460)
      It's the destructive nature that's mutual. In CoRoT-2b's planet, the nature just happens to be self-destructive.
  • by X0563511 (793323)

    Literally tearing it apart with x-rays! That's a mind-boggling amount of energy.

    • ...of what could have been had Mercury been ten million miles or so closer to the Sun: considering how much energy the average Main Sequence yellow dwarf star is emitting (4E+26W), converting nearly 5 million tonnes of matter to energy every second, and that's before you start to consider mutual tidal forces exerted on the Sun by every other body in the Universe (obviously more pronounced for closer bodies such as solar system planets) which not only impart wobbles and bulges but also cause the sun to spin

      • by Anonymous Coward

        ...of what could have been had Mercury been ten million miles or so closer to the Sun: considering how much energy the average Main Sequence yellow dwarf star is emitting (4E+26W), converting nearly 5 million tonnes of matter to energy every second,

        Yes, but the vast majority of that misses a planet mercury's size even if it were plowing through the corona, and our Sun is not a very strong X-ray source. From TFS, it's my understanding that the sheer radiation pressure is causing bulk evaporation of the planet. From the inverse-square law, we could estimate that if Mercury lay 10 million miles closer than its 36 million mile (semi-major axis) orbit, it would receive about (36/26)^2 = 2 times as much solar radiation, or about 12x the Earth's.

        and that's before you start to consider mutual tidal forces exerted on the Sun by every other body in the Universe (obviously more pronounced for closer bodies such as solar system planets) which not only impart wobbles and bulges but also cause the sun to spin at differential and changing rates,

        And is irre

    • by Is0m0rph (819726)
      1.21 gigawatts to be exact
    • by bar-agent (698856)

      So, what would that look like in person? Assuming one could somehow survive on the surface to see.

      Like dust blowing away in the wind? Embers in a fire? Smoke? Like those animations where the light glows through a body as it is ripped to shreds?

  • Old news (Score:5, Funny)

    by Anonymous Coward on Wednesday September 14, 2011 @04:55PM (#37404042)

    Old news. This happened 880 years ago.

    • by subanark (937286)

      I wonder how long it would take to strip the planet away, or at least to the point where it isn't affecting the star enough to produce the energy to do this? Maybe it still is around and it is still happening.

      In any case time is relative.

    • by Nyder (754090)

      Old news. This happened 880 years ago.

      This is slashdot, of course it's old news.

  • Great, so self-destructive codependent behavior is a hard-coded facet of our physical universe. Now I can tell my therapist to fuck off, content in the knowledge that This Is How It's Supposed To Be. /joke

  • In the "Honor Harrington" series, David Weber uses X-Ray lasers, powered by fusion bombs, as missile warheads. As he describes it, at those energies, the laser does mechanical damage due to the momentum transfer (atoms literally pushed aside by the sheer force of the photon avalanche), not just ionization damage or forced fission events.

    Sort of "Real Genius" on hyper-steroids.

    • by idontgno (624372)

      Yeah, fission- or fusion-pumped X-ray lasers are a staple of military hard SF. Footfall [wikipedia.org] was full of them, right at the end, where somehow the US constructed a secret Project Orion [wikipedia.org] battleship with X-ray laser launchers and parasite fighters (Space Shuttles fitted with missile racks in the cargo bays). I call this hard SF, but the technologist inside me was screaming "FANTASY!" the whole time.

      Anyway, speaking of fantasy masquerading as hard technology, SDI [wikipedia.org] was also supposed to build orbital nuke-pumped X-ray

      • by ceoyoyo (59147)

        IIRC correctly, those were gamma lasers. I don't know what your "technologist's" problem was. Footfall didn't have any particularly unbelievable physics. Not even faster than light travel.

        • by idontgno (624372)

          Yeah, all credit to Pournelle and Niven; the technology was feasible. Not the actual creation of an orbital space battleship in months, but the rest of it, sure. Even the alien tech was reasonable for the time (Bussard ramjets, various flavors of laser high-energy laser, hovercraft combat vehicles, centrifugal pseudo-gravity, self-contained biosphere including gardens and biomass recycling, even laser ablation launch).

          The physics were impeccable. It's just the project management and logistics of building Mi

          • by ceoyoyo (59147)

            It's amazing what you can do when you're faced with extinction. Also when you toss the safety regulations.

            All in all a pretty small creative license and certainly nothing to take it out of the hard sci fi category and put it in fantasy.

    • by jgtg32a (1173373)
      Also check out
      http://en.wikipedia.org/wiki/Project_Excalibur [wikipedia.org]
  • ...it could well buy time for itself considering that our own sun, a main sequence star of very average proportions, is converting not quite 5 million tonnes of matter to energy a second...

  • by tuck182 (43130)

    Are you really saying the planet was asking for it?

    • yeah, the bitch had them hotpants ridin' up her crack 'n' all dat... sheeit.

      Commence to modding down.

  • [quote]CoRoT-2b's orbit is likely maintaining the high spin rate of the star, boosting magnetic activity, thus boosting the X-ray output.[/quote] So, we've found the first suicidal planet?
  • by Anonymous Coward

    Assuming the same weight as the earth, that's how long it would take to strip this.

    The earth weights 5.9722 * 10^24 kg. That's 5,972,200,000,000,000,000,000,000 kg. Or 5,972,200,000,000,000,000,000 ton. At five million tons per second, that'll take 1,194,440,000,000,000 seconds to strip. That's 13,824,537,037 days, or 37,850,296 years.

    Eivind.

    • by PPH (736903)
      But after even a few minutes, who will be left to worry about it?
    • Re:37 millon years (Score:5, Informative)

      by Ruke (857276) on Wednesday September 14, 2011 @05:57PM (#37404614)
      COROT-2b is much, much larger than earth. It has a mass of approximately 3.31 times that of Jupiter, which itself is 317.83 times that of earth. (COROT-2b [wikipedia.org]) Your estimate is off by about three orders of magnitude, assuming a constant rate of decay.
      • I started with a different weight for the earth, which I got from here: http://coolcosmos.ipac.caltech.edu/cosmic_kids/AskKids/earthweight.shtml [caltech.edu]

        Otherwise, I'm in the same ballpark that the AC got:

        13,170,000,000,000,000,000,000,000 Earth, in pounds
        6.585E+21 Earth, in tons ( / 2000)

        5000000 Rate of decay per second, in tons
        1.317E+15 Seconds to eradicate Earth ("in tons" / "rate of decay per second")
        2.195E+13 Minutes ( / 60)
        3.65833E+11 Hours ( / 24 )
        15243055556 Days ( / 365)
        41761796.0

        • by Anonymous Coward

          You're off in both making the complete bullshit asspull assumption that a hot jupiter weighs the same as the earth. It weighs 3 orders of magnitude more, so it'll take 3 orders of magnitude longer.

          And don't even try "but he said, 'Assuming the same weight as the earth', so it's OK" -- you can't just make one asspull for one part of a problem and assume it remains the same problem. Once you reduce the mass by 1000, you reduce tidal forces similarly, and the planet is likely no longer capable of driving the s

    • by Tim C (15259)
      Mass, not weight. If you're going to produce an estimate like this at least get the terminology right.
  • Some math (Score:5, Informative)

    by Anonymous Coward on Wednesday September 14, 2011 @06:03PM (#37404652)

    At 3.3 times the mass of jupiter, it's mass is about 6.2 * 10^27kg.

    5 million tons = 5*10^9kg.

    (6.2 * (10^27)) / (5 * (10^9)) = 1.24*10^18. It'll take that many seconds for the start to completely evaporate, assuming mass loss continues to be linear.

    That's about 39 billion years, 2.8 times greater than the age of the universe.

    The star (together with the planet) will die of something else long before the planet dies of this "ripping to shreds".

    • As it goes on there's less mass for the X-Rays to interact with and blow off, so there rate should decrease.

    • by torgis (840592)

      "Evaporation" of the planet might depend on surface area as well. The surface area of a sphere can be represented by A = 4*pi*r^2, so as r->0, A->0 as well. The smaller the planet gets, the smaller the surface area, obviously.

      A second consideration would be the amount of matter ejected per second in relation to total mass of the planet, and whether this stays constant. TFA does not list the diameter of the planet in question.

      Something along the lines of m = (matter ejected per second), A = 4*pi*r^2

  • I hear that astronomers are planning to name the planet "Federline".

  • by suss (158993)

    I saw this in an episode of Sliders, only with Earth.

  • Exoplanet is just exo- sorry, techno-babble. Are we still so tentative about the concept of planets around other stars that the word needs to be qualified? I'm fairly sure that Flash Gordon and Lensmen just visited regular old fantastical planets, not "exo" planets.

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