#stellar navigation

The previous parts have covered the front limb and latitude plate. Unlike the latitude plate, the main body of the astrolabe (the mater) is the same across all astrolabe

The various rings on the back of the plate determine the altitude and calendars (civil and zodiac)

This is a step-by-step guide to the complete construction of an astrolabe that I think might exist. At least, in any accessible form

As always, my goal is for this to be as accessible as possible for any kind of reader, so if there are any questions, please feel free to reach out

Plate to represent the Unequal Hours Arcs

The plate currently shows the various arcs for almucantar and azimuth (see part four). The new section will cover the fun (but sometimes confusing) construction for the unequal hours! They form 12 segments from 11 lines radiating from the below previous sections.

This is a step-by-step guide to the complete construction of an astrolabe that I think might exist. At least, in any accessible form

As always, my goal is for this to be as accessible as possible for any kind of reader, so if there are any questions, please feel free to reach out

The outer limb of the main body measures altitude and time

The previous parts have covered how to build the latitude plate that lies in the heart of the astrolabe. The plates vary based on latitude, however the main body of the astrolabe (known as the mater) is a constant among all astrolabes

Along the outer rim of the mater, the front limb contains a series of rings. Each ring contains information that can be used to measure the height of stars, and in turn, time

This is a step-by-step guide to the complete construction of an astrolabe that I think might exist. At least, in any accessible form

As always, my goal is for this to be as accessible as possible for any kind of reader, so if there are any questions, please feel free to reach out

Plate to represent the Horizon, Almucantar, and Twilight Arcs

The plate currently shows three concentric circles for the Tropic of Cancer, Tropic of Capricorn, and the equator. This next part builds off the base plate and adds more arcs and circles

The middle plate--known as the Tympan--is perhaps the most complex piece of the entire astrolabe, so this is part three of constructing the plate and only part two of specifically constructing the tympan plate

The circles on the face of the plate represent “almucantar” and twilight arcs.

This is a step-by-step guide to the complete construction of an astrolabe that I think might exist. At least, in any accessible form.

My goal is for this to be as accessible as possible for any kind of reader, so if there are any question, free free to reach out

Plate to represent the Tropics and the Equator

The construction continues into part two!

The middle plate--known as the Tympan--is perhaps the most complex piece of the entire astrolabe, so I am going to be breaking it into a few parts to make it more readable

The first part starts with just three concentric circles for the Tropic of Cancer, Tropic of Capricorn, and the Equator.

No math needed!

This is a step-by-step guide to the complete construction of an astrolabe that I think might exist. At least, in any accessible form.

My goal is for this to be as accessible as possible for any kind of reader, so if there are any question, free free to reach out

Plate to represent the Azimuth Arcs

The plate currently shows the concentric circles for the Tropics and equator as well as the arcs for the almucanter circles (see part three). This new section will cover azimuth arcs! They are the spider web looking lines in the center of the plate.

The middle plate--known as the Tympan--is perhaps the most complex piece of the entire astrolabe, so this is part four of constructing the plate and only part three of specifically constructing the tympan plate

This part is perhaps the most difficult of all the steps since uses a new kind of projection method, but it ends up being quite beautiful when the pieces are done

This is a step-by-step guide to the complete construction of an astrolabe that I think might exist. At least, in any accessible form

As always, my goal is for this to be as accessible as possible for any kind of reader, so if there are any questions, please feel free to reach out

Sometimes also called a Pillar Dial or a Shepard Dial

This strange looking device is actually a portal sundial! The metal arm is the “gnomon” (the part of the sundial that casts a shadow) and the body is carved with different curved horizontal lines for times and vertical columns for months

This sundial is set for the 37th parallel north (37.3 degrees North latitude) which includes places like the island of Sicily, Greece, as well as places in Syria, Iran, China, and through the center of the United States. This kind of information can make it possible to determine where this device was originally made or at least where it was intended to be used 🔎

Helpfully, it also just so happens it is “inscribed on the dial corresponds with that of Catania in Sicily” so this device was likely made to operate in Sicily

(A very simple) Mystery solved!