Product Spotlight: Stars on the Quadrant
2024-02-10
We're reaching for the stars here. Quadrants, derived from astrolabes, in fact, folded-up astrolabes, are astronomical instruments that are used for naked-eye observation as well as celestial navigation, using the stars to achieve these objectives.
The rete on an astrolabe[1] is the place where the stars reside, a typically small number of navigational stars that are easy to locate in the sky and visible across larger time frames. This set of stars is dependent on the latitude of the observer and the instrument that is made for that latitude (or set of latitudes).
Some historical Quadrants also show stars, namely the Gunter Quadrant,[2] among others.
One could argue about the usefulness of a small set of stars on such a small device, but there are a number of reasons to include at least one star per season: we can teach the concepts of celestial declination, and longitudinal positions, we can demonstrate the concept of right ascension, and we can use these stars to directly practice calculations and conversions between coordinate systems. We can even use the hour lines to measure and calculate time, just like with the sun. In addition, we now have stars on our Quadrant -- a map of the heavens! Which explorer does not want to reach for the stars?
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