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Out of this Solar System

Discussion in 'Environmental Discussion' started by RCO, Oct 28, 2017.

  1. RCO

    RCO Senior Member

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  2. fuzzy1

    fuzzy1 Senior Member

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    From another source, I believe the orbital parameter 'e' was being curve fit to about 1.19. I.e. hyperbolic orbit, on an escape path, so it is not bound to the sun.

    For those unfamiliar, objects in bound orbits have e < 1. Circles have e = 0, ellipses (ovals) have numbers between 0 and 1. (Earth at 0.017, all other major planets except Mercury less than 0.1) E = 1 is a parabolic path, those with e > 1 are hyperbolic paths.

    Some comets have been thought to be hyperbolic, but they were likely being ejected by a gravitational dance with other bound objects, and e would have only barely been above unity. (Some may be been reclassified to sub-unity, barely bound to the sun, based on later observations.) But this one appears to be moving much too fast for that. Thus it must be a 'visitor'.

    =============
    PS. Some discussion:
    Pseudo-MPEC for A/2017 U1

    PS2. Here is what should be the best list of known objects with e > 1, i.e. on escape paths from the sun. #2 on the list, with e = 1.0577, is mentioned in the above link as having been ejected from the Solar System by a close encounter with Jupiter. Prior to that encounter, it had e < 1, just barely. Other bodies either should be in similar situations, or had significant observational uncertainties.
    JPL Small-Body Database Search Engine
     
    #2 fuzzy1, Oct 28, 2017
    Last edited: Oct 28, 2017
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  3. fuzzy1

    fuzzy1 Senior Member

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  4. bwilson4web

    bwilson4web BMW i3 and Model 3

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  5. RCO

    RCO Senior Member

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    You guys should read "Slabworld" and all would become clear....
    .. or not!
     
  6. bisco

    bisco cookie crumbler

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    it's probably mork from ork.
     
  7. Fester

    Fester Active Member

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    In the Doomsday department, we don't need any help...
     
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