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NASA Preps Closest-Ever Sun Mission

Posted by timothy on from the ask-your-actuary-if-you'll-be-around dept.

coondoggie writes "NASA today said it had picked five experiments that will ride aboard one of its most ambitious space missions to explore the Sun. The Solar Probe, a car-sized spacecraft, is scheduled to launch no later than 2018 and will fly closer to the Sun's surface than any other probe, NASA stated. Ultimately the spacecraft's goals are to help scientists understand why the sun's outer atmosphere so much hotter than the sun's visible surface and what propels the solar wind that affects Earth and our solar system, NASA said."

12 of 111 comments (clear)

  1. Pfst... by bigredradio · · Score: 4, Funny

    I don't see all the fuss. Why not just go at night?

    --
    Flexible bare-metal recovery for Linux/UNIX
    1. Re:Pfst... by Anonymous Coward · · Score: 5, Funny

      I don't see all the fuss. Why not just go at night?

      You mean, when the sun is beneath the earth? You can't launch a rocket into the ground, dumbass! The Soviets have tried, repeatedly. ...besides, it'll be hard to find in the dark..

    2. Re:Pfst... by JustOK · · Score: 4, Funny

      a cloudy day during an eclipse on the winter solstice.

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      rewriting history since 2109
    3. Re:Pfst... by h4rm0ny · · Score: 3, Funny

      I don't see all the fuss. Why not just go at night?

      If you bothered to read a bit more about the probe (yeah, it's Slashdot, who bothers to read?), you'd learn that the probe is going as close as 3 Solar Radii to the surface. The Sun's radius (it is correct to assume equatorial radius rather than mean radius for this purpose), is 6.955×10^5 km, meaning the probe will get as close as 2.087 x 10^6km at which point it states the solar radiation will have been sufficient to heat the probe to 2,550 degrees Fahrenheit.

      Now, that radiation will not suddenly appear at a distance of 3 solar radii. The temperature is an accumulation of the radiation on the journey to that point as well as (and this is perhaps where you went wrong), that accumulated on the return journey up until the point that rate of heat absorption is exceeded by the rate of heat dissipation. What that means, is that although you propose "going at night" as a solution, the probe would in fact have to make it not only too a distance of 3 Solar Radii from the Sun during the hours of night, but also make the journey back again to a safe distance before morning. Even if they timed the mission during Winter (and this is irrelevant as the team are going for a May launch), you'd still face a limited window of around twelve hours. The rate of heat absorption from the Sun's energies will follow an inverse square law and I think it reasonable to consider significant heat build up therefore to kick in around 5 solar radii distance. Remember that heat dissipation in a vacuum is no trivial matter! So basically, in those twelve hours, you'd not only have to traverse a distance of 1.4*10^6km, but completely reverse your momentum to turn around and go back again. This is obviously unfeasible. Even if a spacecraft could be built that could take this sort of stress (strictly in the realms of sci-fi for now), you'd never carry sufficient fuel to generate this amount of energy. True, you could launch your probe from the extreme North or South, where night lasts much longer, but polar launches are extremely extravagant users of fuel - it is pretty much a requirement to launch from the Equatorial band.

      So in short, your idea is a nice fantasy, but impractical if you actually understand the Physics involved.

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      Aide-toi, le Ciel t'aidera - Jeanne D'Arc.
  2. When it comes to naming the mission... by jenningsthecat · · Score: 5, Funny

    ...I hope they don't decide to call it Icarus

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    'The Economy' is a giant Ponzi scheme whose most pitiable suckers are the youngest among us and the yet-unborn.
    1. Re:When it comes to naming the mission... by SIGBUS · · Score: 3, Insightful

      I was thinking that they stole Hotblack Desiato's stuntship.

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      Oh, no! You have walked into the slavering fangs of a lurking grue!
  3. I thought they already knew why corona is hotter.. by Ungrounded+Lightning · · Score: 5, Informative

    Ultimately the spacecraft's goals are to help scientists understand why the sun's outer atmosphere so much hotter than the sun's visible surface and what propels the solar wind ...

    I thought they'd figured that out (recently): Vibrations of the solar magnetic field line loops pump energy into the plasma fraction of the gas above the visible "surface", heating it. Reconnection of the lines cause the new loops to expand like released springs, catapulting the entrapped plasma outward.

    Didn't that work out once they finished the math on the details?

    --
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  4. We're going to need a REALLY black ship. by Shag · · Score: 3, Funny

    And a depressed robot to open it.

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    Village idiot in some extremely smart villages.
    1. Re:We're going to need a REALLY black ship. by MichaelSmith · · Score: 4, Funny

      Be sure to equip it with a working teleport, even though it does have a perfectly serviceable door.

      --
      http://michaelsmith.id.au
  5. Re:Dipshits by Man+On+Pink+Corner · · Score: 4, Funny

    Can't you dipshits go back to Digg?

    I liked the annual September flamefest better when it was Usenet vs AOL.

  6. Re:Actively radiating heat to get even closer? by bertok · · Score: 4, Informative

    The Russians were faced with the same dilemma.

    They used a mirror.

    You joke, but that's precisely what everyone does already. That gold foil that you see covering spacecraft is used because gold is an excellent reflector of infrared light.

  7. Re:I thought they already knew why corona is hotte by f3r · · Score: 3, Informative

    from what I know, all that is based on heavy numerical simulations (prone to errors in the assumptions, lack of more thorough numerics, etc). The simulations are based on parameters determined from measurements made from distances longer than those that will be reached with this new probe, and on assumptions also extrapolated from everything observed "from here". Summed up, that explanation could be right or completely wrong. We have to measure more and from smaller distances.