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"David Weinshenker" <daze39@xxxxxxxxxxxxx> wrote in message
news:480CE8CC.47595263@xxxxxxxxxxxxxxxx
| Chris L Peterson wrote:
| >
| > On Mon, 21 Apr 2008 10:48:09 -0700, David Weinshenker
| > <daze39@xxxxxxxxxxxxx> wrote:
| >
| > >How would you measure the rotation: suppose you landed on this planet
| > >from outer space, with your own time-measuring devices (that were
marked
| > >in some totally alien units, independent of Earthlings' "hours"), and
| > >were wondering what the rotation period of the planet was. By what
| > >observation would you take that measurement? (Observing the apparent
| > >position of distant stars? Observing the position of sun? Using a
| > >Foucault pendulum at the pole?)
| >
| > Which is very much the situation with us as the "aliens" when we measure
| > the rotation period of every other body in the Solar System. We specify
| > the period with respect to the stars (which is exactly what you would
| > get with an inertial measurement, of course). In some cases, we
| > _measure_ with respect to something else, such as an orbiting
| > spacecraft. But then we convert to the inertial (sidereal) value.
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| Yeah, it seems that such distinctions are lost on "oriel36", who
| seems to believe that there is something inherent or absolute about
| the "24 hours = 360 degrees of rotation" relationship (independent
| of how that rotation is measured), appears to be unaware that the
| observation of stellar transits -is- a way of "isolating axial
| rotation as an independent motion to be checked". and appears
| not to have spent enough time observing the night sky to note
| that particular stars do in fact rise "earlier" (relative to
| the solar day of terrestrial timekeeping) each night.
|
| -dave w
Several years ago I suggested to Kellerher that he aligned
two poles in his backyard with a star he'd recognise again,
note the time of alignment with his wristwatch and then check
again on the next few nights. Needless to say his bigotry
precluded him from carrying out such a simple test.
Such people are simply not worth bothering with, he'd rather
rant that Flamsteed and Newton were the originators of a malicious
conspiracy to which those that own clock-driven equatorial mounts
even to this day are party to.
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