The Nocturnal Celestial Stardial! This long-forgotten instrument aided a few lucky navigators and charmed romantics of the Renaissance. Earliest references include Cosmographicus Liber in 1530, Arte de Navegar, in 1551, and Horologiographia, The Art Of Dialling in 1626. 'Twas rare then as now. The Nocturnal Celestial Stardial is also called a stardial, a nocturnal, a "horologium nocturnum" (time instrument for night), or nocturlabe.
Time-Journey Tool 1 of 6, it needn't even be configured to longitude and latitude like a sundial.
ï· an Eyelet or Rivet (Eyelet kits may be purchased in craft or fabric stores, even Sears. Paper fasteners will not work because a hole is needed at the center of the instrument for sighting the North Star.
ï· Printer with Paper or Cardstock
ï· Scissors or X-Acto knife
ï· Hammer and eyelet kit or dowel rod
Step 1: Choose Color Scheme
The outer disc is marked with the months as well as an indicator for each of the 365 days of the year. The inner disc is marked with hours and 5-minute increments. The pointer rotates on the same center axis as the discs. The center axis has a sight hole through which the North Star Polaris can be aligned.
In the northern hemisphere, all stars will appear to rotate about the North Star, aka Polaris. The North Star is very close to the north celestial pole, but about 434 light years away.
The time can be read on my Nocturnal Stardial from any of three reference constellations: Big Dipper (Ursa Major), the Little Dipper (Ursa Minor), or Cassiopeia.
- paper stardial kit gray.pdf
- paper stardial kit green.pdf
- paper stardial kit blue.pdf
- paper stardial kit purple.pdf
Step 2: Chop Chop!
Grab some scissors or an X-Acto knife and cut out the three shapes in the PDF document printed in the previous step. Cut around the perimeter of each of the 3 pieces. Also cut the 3 center holes.
Hint: if you have access to a method of paper lamination, consider it, particularly if you intend to take to sea.
Step 3: Stack 'em!
Step 4: Insert Eyelet
Incidentally, eyelets, rivets, and grommets are all pretty much the same thing. Crafts stores like Michaels, AC Moore or Overstock.com are good places to get an eyelet kit for $5-20 dollars. If you're handy you could probably buy 100 or more eyelets for $3. bucks and use a hammer and a piece of wood or metal rod.
Step 5: Smack It
Tap down the edges of the fastener with the hammer so that they become flattened to the cardstock.
Step 6: How to Use the Nocturnal Celestial Stardial
1.) Find one of the 3 reference constellations, the larger reference star of it in particular.
2.) Align the appropriate constellation dial (Dial B) to the day's date.
3.) Hold instrument in a vertical position whilst facing north.
4.) Sight Polaris, the North Star, through the hole in the center of the instrument.
5.) Rotate the long arm (Dial A) to point to the reference constellation.
6.) The time units on Dial B are in 5-minute increments. The flat edge of Dial B will show the time increment to the nearest 5 minutes.
Note: for greater accuracy one could point directly to specific stars within the chosen constellation:
ï· Schedar within Cassiopeia
ï· Kochab within Ursa Minor (the Little Dipper)
ï· The Pointers within Ursa Major (the Big Dipper)
Step 7: Make More!
A kid with some scissors can make a workable model. This makes a great family or class project.
note: these illustrations show meticulous cutting around the outer perimeter. But the fact is if you pretty much cut a circle, it'll work fine.