Thank you for your questions

Apr 20, 2019,03:37 AM
 

Hi Dirk, The watch is made for my location which is 50 degrees latitude north with the North Pole as projection point. It gives the date, local time, position of the sun on the ecliptic, position of the moon on the ecliptic, position of the ascending and descending nodes of the orbit of the moon (dragon hand), state of the ecliptic compared to the horizon and the sun/moon eclipses. Basically, once the watch is set you don't want it to stop. To set the watch is very complicated, especially when you have to find the correct position of the dragon hand. When it is not running for a short period of time you can set the correct date by finding the next or last full moon (when the moon and sun hand are opposite of each other) and forward day by day from there. When I am not wearing this watch for more than one day I use my CvdK programmed Swiss Kubik winder to keep it perfect on time. To give you an idea of the dynamics: The dragon hand in the zodiac ring currently points to the year 2019 which is between Leo and Cancer. The sun and the earth remain always in the ecliptic plane but the moon moves around the earth in a plane with an inclination of approx. 5 degrees compared to the ecliptic. The orbit of the moon therefore has two points of intersection with the ecliptic plane and are indicated by the dragon hand. The position of the nodes move approx. 19 degrees in opposite direction of the movement of the sun and moon. The solar time is indicated by using 24 hours with the black dots (see left part of the picture). For example: in my picture the my local time is 6.37pm and the solar time is 17.49 (start counting from 12.00 and the first black dot is 13.00 etc.). You can check this by using the website www.pveducation.org which will give you an idea of the calculation. To get an idea of the sunrise and sunset functionality (see right part of the picture) the sun rises at 7.10 and sets on 16.48 local time, indicated by the sun hand. I hope this answered your questions. Br, JW



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Very rare and beautiful CvdK 👌🏻

 
 By: Watchonthewrists : April 19th, 2019-11:33
Thanks for sharing 🤗

Astrolabium

 
 By: jwk : April 19th, 2019-12:02
Thank you! Astrolabs are extremely fascinating and it is by far my favourite daily beater.

Not bad at all for a daily beater!

 
 By: mrds : April 19th, 2019-14:18
The astronomic display will help to keep our lifes inperspective. So many of our so important issues will evaporate without a trace when looking at them from the moon. Thank you for sharing this unusual piece. Best, Daniel

Wow!

 
 By: LS : April 19th, 2019-11:57
An astrolabe for the wrist!

Thank you [nt]

 
 By: jwk : April 19th, 2019-13:15

Now that is something you don’t see very often.

 
 By: NoH : April 19th, 2019-13:08
If at all..! Wear it in good health! All the best, Niall

Thank you!

 
 By: jwk : April 19th, 2019-13:16
Good to wear, understated and very precise <1 sec per day deviation

Astronomical wristwatches are an extremely rare breed ...

 
 By: Marcus Hanke : April 19th, 2019-13:45
... and I absolutely adore them. Besides Ludwig Oechslin/Ulysse Nardin, Mr. van der Klaauw was always a personality I admired. I love all his watches, but of course his astronomical timepieces are my favourites! Marcus

thanks for the post ! Simply LOVE and admire your watch even though I have...

 
 By: GLau : April 19th, 2019-15:41
NO idea how to read it and cannot understand the functions ! LOL !!

Thanks for your comment

 
 By: jwk : April 20th, 2019-03:41
It takes a while to get used to the watch and understand everything what is displayed.

Fascinating watch

 
 By: dedestexhes : April 19th, 2019-21:22
so I understand you can see the sunrise and sunset? Is it made for your location? Is it dynamic, is the horizon changing? Sorry for all these questions but I LOVE your watch! Br, Dirk

Thank you for your questions

 
 By: jwk : April 20th, 2019-03:37
Hi Dirk, The watch is made for my location which is 50 degrees latitude north with the North Pole as projection point. It gives the date, local time, position of the sun on the ecliptic, position of the moon on the ecliptic, position of the ascending and ...  

Fantastic piece from VdK! [nt]

 
 By: Tim Jackson : April 20th, 2019-14:51

Thank you Tim [nt]

 
 By: jwk : April 21st, 2019-01:14

For those who are interested in the backside of the watch.

 
 By: jwk : April 22nd, 2019-12:14
Hand engraving by Jochen Benzinger. ...  

Wow, that’s awesome

 
 By: donizetti : April 26th, 2019-02:23
Thanks for sharing! Which was first, this or the Oechslin/Ulysse Nardin piece? Superb dial. Best Andreas

Thank you for your question

 
 By: jwk : April 26th, 2019-03:25
Hi Andreas, The Ulysse Nardin Astrolabium Galileo Galilei was introduced in 1985. This series of Christiaan van der Klaauw Astrolabium was available from 2005.

Thanks again

 
 By: donizetti : April 30th, 2019-10:57
glad that the art of astronomical complications is kept alive! Best Andreas