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Mariner's Astrolabe Geocoin JohnnyM.'s Astrolabe Geocoin

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JohnnyM. Send Message to Owner Message this owner
Monday, 02 February 2009
Recently Spotted:
In the hands of the owner.

This is collectible.

Use TB2V1D6 to reference this item.

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Current GOAL

To be in small collection of my owner.
I want to travel from event to event with my owner.
You can see me in the hands of JohnnyM. mostly stays in Prague (Czech Republic).

About This Item


How to use me:

Taking a latitude reading from the North Star, Polaris:
  1. Grasping the ring, hold the astrolabe up in the air towards the North Star.

  2. Line up the holes in the spinning alidade so that you can see Polaris through them.

  3. Take the reading from the degree scale and you now have your latitude.

Measuring the declination of the sun:
  1. Grasping the top ring, hold the astrolabe to about chest high.

  2. Looking down on the alidade, let the sun shine directly though the upper alidade hole.

  3. Adjust the alidade so that the beam of sunlight shinning through the upper hole passes through the lower hole. The picture below shows how the light and shadow from the upper alidade look when slightly misaligned with the lower alidade hole.

  4. Now you can take a reading from the degree scale and see the declination of the sun. In this example, the degree scale shows the sun is at 11 degrees. These example photographs show the angle of the sun during the evening to give better contrast of the sunlight passing though the hole. When using the Mariner's Astrolabe Geocoin™ for navigation, you will want to take a reading at high noon.

Gallery Images related to JohnnyM.'s Astrolabe Geocoin

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Tracking History (474.7mi) View Map

Discovered It 10/03/2019 Haedel 80 discovered it   Visit Log

Danke fürs zeigen

Discovered It 09/01/2019 mediasphere discovered it   Visit Log

Widziane na keszerskim szlaku Spotkaniach Eventach :( Niestety dopiero teraz nadrabiam zaległości Które się namnożyły

Discovered It 08/31/2019 ivans discovered it   Visit Log

Seen during mega-event in Prague, thanks.

Discovered It 07/22/2019 PetjeOp discovered it   Visit Log

Discovered in a yt video 😊 Thanx so much for sharing!

Discovered It 07/13/2019 gégé57 discovered it   Visit Log

Vu dans la video GPS Maze

Discovered It 07/08/2019 jackyannetrott discovered it   Visit Log

Vu dans la vidéo GPS maze de geonord .

Discovered It 07/01/2019 Belugue discovered it   Visit Log

Seen in the video "GPS Maze Europe 2015"on the GeoNord Mega Event site. Thanks for sharing

Discovered It 06/01/2019 DVERK discovered it   Visit Log

Saw this TB during the last time by visiting a mega, giga, event, normaly cache or something else. Thanks for sharing.

Discovered It 04/28/2019 Mazurteam discovered it   Visit Log


Discovered It 04/28/2019 Waczurki discovered it   Visit Log


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