Independents

Marcus Hanke
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I think there might be a small mistake in the press text, regarding the solar time ...

If the sun hand is set to the solar time, the difference between the regular time display and the sun hand is by no means the equation of time. The regular hour and minute hands indicate the so-called civil time, as legally introduced in a specific country, roughly following the longitude-dependent 24 time zones. Then, there are two different solar times: The true solar time is indicated by a sundial on the exact spot one is residing. This depends on the longitudinal position; the farer westward one is located, the later is noon there.

However, the Earth's orbit around the sun is not a circle, but elliptic, additionally, the Earth is not upright, but its rotational axis is slanted. Therefore, the periods from one noon to another in the same place normally does not last exactly 24 hours (only twice a year). The deviation of the "true solar time" from the "average solar time", that is always escatly 24 hours long, is calculated by the equation of time.

From Alex' text I conclude that the Vianney's solar hand is already corrected for the equation of time, which of course would make an annual calendar mechanism necessary for setting the watch. Otherwise, the equation of time would not be correct. So the watch does not display the "equation of time", but the true solar time, corrected according the equation of time. The difference between the standard minute hand and the sun hand therefore only indicates the difference between the time when your stomach feels hugnry for lunch (solar time), and the time you are allowed to leave your workdesk for lunch break (civil time).

Regards,
Marcus

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