Hi Moses, thanks for catching my error. I am talking about two different frames of reference, or starting, or observation points. Time is a repetitive interval of motion (rotation) with a starting point and an observation location. Starting point is spring equinox, observation location is Earth, and time is the repetitive return of the equinox (365.24 rotations). Keeping the same starting point: spring equinox, but changing the observation location: distant star, changes the repetitive interval of motion: time (366.24 rotations). Observing a horse race from the center of an oval track, the horse has zero rotations per orbit; from the bleachers, one rotation per orbit. Time depends on your observation frame of reference.moses wrote:"Earth rotates 364.24 days from spring equinox to spring equinox."
Obviously not, did you mean rotates 364.24 times per year? If so then you'd be wrong. Each day the Earth rotates once plus a little bit lasting about 4 minutes. So in one year Earth rotates 365.24 times plus 365.24 x 4minutes = one day, near enough. So the Earth rotates 366.24 times per year, near enough.
Kepler was wrong
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Re: Kepler was wrong
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Re: Kepler was wrong
Jtb,
You keep introducing observations from a distant star.
That is where the confusion comes in. IMO
A different "frame of reference" does not mean a different place of viewing in this case.
It means a different way to mark the end of a rotation.
Noon to noon uses the sun to measure a rotation.(24 hours)
Using the same star at night to start and end a rotation gives a different answer.(24 hours plus four minutes)
The place of viewing is the same,(Your spot on the earth). The determination of what is a single rotation(The sun or the stars directly overhead) is the different frame of reference.
Jack
You keep introducing observations from a distant star.
That is where the confusion comes in. IMO
A different "frame of reference" does not mean a different place of viewing in this case.
It means a different way to mark the end of a rotation.
Noon to noon uses the sun to measure a rotation.(24 hours)
Using the same star at night to start and end a rotation gives a different answer.(24 hours plus four minutes)
The place of viewing is the same,(Your spot on the earth). The determination of what is a single rotation(The sun or the stars directly overhead) is the different frame of reference.
Jack
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Re: Kepler was wrong
Thanks for correcting me, Jack. My grandkids gave me a cup for Christmas that says "Papa knows everything, and if he doesn't he makes stuff up real quick".
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