Apian Nocturnal (ca. 1520 AD)


Brass, lenght 135 mm, weight c. 90 grams
CHF 380.00, EUR 330.00

Apian Nocturnal (ca. 1520 AD)

The nocturnal enables time-finding by night with the stars Polaris (alpha UMi) and Kochab (beta UMi) of the little dipper. Some instruments are constructed for alpha and beta UMa (big dipper), two stars pointing to the northern celestial pole. The back shows an illustration (following Peter Apian, 1524), how to use the nocturnal. Adjust the pointer of the dented disc to the date. Hold the nocturnal with vertical handle to the northern sky and find the pole-star through the central hole. Turn the long pointer to the star Kochab (beta UMi) and read the (local) time on the dented disc. The dents serve to read time in darkness with the finger-tips. The reconstruction shows Julian date (0° Aries = 12th March), and today you have to correct the date by 9 day.
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