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Would anything survive our sun's eventual nova?

  1. Jul 17, 2009 #1
    We know our sun will eventually become a read giant, and go nova. Is anything expected to survive?

    The expected size for a red giant encloses our orbit unless I'm mistaken, so that's it for earth. Is there any chance for the massive jupiter or any ort cloud objects?

    I assume any solar-system like objects without their parent suns around would be unobservable whereas they don't give off any EMR at all.

    Here's another thought. Should it be that it all goes to waste and we've done nothing other than the pioneer and voyager plates, are they going fast enough to survive the nova?
     
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  3. Jul 17, 2009 #2

    negitron

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    No, our Sun will not go nova--it's not nearly massive enough. After it bloats up into a red giant (entirely consuming the inner planets up to the orbit of Mars in the process) it will slowly fade away into a white dwarf. The outer planets should remain largely intact in their orbits, although their composition may suffer.
     
  4. Jul 17, 2009 #3

    Vanadium 50

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    I assume you mean "red", but yes.


    ...and no.
     
  5. Jul 17, 2009 #4

    Nabeshin

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    Interesting that you know this, because the sun is not going to go nova. The red giant thing is a concern, though (if you want to call it that). I don't think there's conclusive evidence whether or not the earth will be enveloped, it's really difficult to predict with that measure of accuracy.

    As far as the voyager and pioneer space probes, they're traveling at approximately v=15km/s. Since the sun is expected to stay on the MS for at least the next 4 billion (to be conservative) years, the probes would be an estimated 200,000 ly distant by that time, barring any encounters with other bodies. This distance is roughly twice the galactic diameter. (This assumes the spacecraft is traveling on a straight path, which it undoubtedly is not. But you get the idea. They'll be long gone.)
     
  6. Jul 17, 2009 #5
    Interesting stuff. Thanks.
     
  7. Aug 5, 2009 #6
    Actually they won't escape the Galaxy and if pointed in the right direction, they might eventually re-encounter the Sun. With a relative velocity between them and the Sun of just 15 km/s that means they do a lap around the Galaxy once every ~ 3 billion years before returning to the vicinity of the Sun. In two laps time they'll return as the Sun starts climbing the ascent to Red Giant, which really doesn't take off until c.7.5 billion years from now, but begins about 6 billion years from now.
     
  8. Aug 6, 2009 #7
    This brings up an interesting question: could we design a probe (today) that would eventually return to Earth's orbit after making a "lap" around the galaxy?

    Would make for an interesting time capsule!
     
  9. Aug 6, 2009 #8

    negitron

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    Probably not if for no other reason than nothing we can currently construct could survive the beating of hundreds of millions of years in deep space. It might make it back but it would be a pile of crumpled metal Swiss cheese.
     
  10. Aug 6, 2009 #9

    Nabeshin

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    Can't remember the source off the top of my head but I remember reading somewhere that it would not be outlandish to expect the probes to last for that amount of time in interstellar space. If you run into gas clouds or through solar systems, then it becomes a bit more of a problem.
     
  11. Aug 6, 2009 #10
    I just finished reading "The 5 Ages of the Universe" by Fred Adams and Greg Laughlin, and there was a bit in the beginning describing the vast emptiness of the universe -- that if you were to travel in a straight line in space the odds of you hitting something are 1 in a billion trillion.

    So probably the main issue would be, as the probe orbits around the galaxy, to have enough fuel to adjust it's course to eventually return to Earth.
     
  12. Aug 6, 2009 #11
    I always thought 'empty' space wasn't actually 'empty' at all. I assume the authors meant 'substantial object' which you could actually 'hit' and not have just attempt to shoot through you without you noticing.
     
  13. Aug 7, 2009 #12
    Interstellar dust impacting a probe at 15 km/s would probably abrade it over the aeons, but I don't have any figures for just how much can be expected. But we can get a rough idea. At 15 km/s one travels through a path some 50,000 light years long every billion years. A dust speck ~1012 daltons in mass will probably collide with a square metre of frontal area every 1,000 kilometres, and there's about a million protons per cubic metre. Thus a volume containing ~ 1.58 kg of material is traversed every billion years. That means some small multiple of that will be knocked off the probe's frontal cross-section by abrasion.
     
    Last edited: Aug 7, 2009
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