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Time Earth reached its Perihelion

  1. Jan 11, 2012 #1
    On 1-4-12 the Earth reached its Perihelion.

    It is the closest Earth's radius to the Sun in its ellipse.

    I have a few sources that have conflicting accounts about the TIME this happened.

    Could someone give me a definitive source to clarify my discrepancies of clock differences.

    One said 1-4-12 @10:59PM EST, other varied from 0:00Mid to 6:00AM that same day.
     
    Last edited: Jan 11, 2012
  2. jcsd
  3. Jan 11, 2012 #2

    D H

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    January 5, 2012 at 00:33 (TT).
     
  4. Jan 11, 2012 #3
    Do you mean January 5, 2012 @00:00:33TT which translate to Ephemeris Time Jan 5, 2012 @00:00:0.816ET?
     
  5. Jan 11, 2012 #4

    D H

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    No, I meant 33 minutes after midnight (TT), just as I typed it. That is the time at which Earth-Sun range rate went from negative to positive per JPL Horizons. I wouldn't put too much stock in timing this down to the second.
     
  6. Jan 11, 2012 #5
    From the Barycenter Earth-Moon model in JPL Horizons with @sun as the center. The smallest Helio range "r" and the Helio rate changing positive has a date of January 4,2012 @3:00(TT). Why is it different to your perihelion of January 5, 2012 at 00:33 (TT)?
     
    Last edited: Jan 11, 2012
  7. Jan 12, 2012 #6

    D H

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    You used the Earth-Moon barycenter. I used the Earth. Earth perihelion passage is the time at which the Earth is closest to the Sun, not the Earth-Moon barycenter.
     
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