Again : 25. the declination of the Sun 26. the beginning of the sidereal day (for amateur astronomers ) 27. the sidereal time 28. after how long a constellation will pass above us 29. the instant when the Sun is exactly South and therefore the direction of the South 30. the direction of cardinal points 31. the direction of particular cities - Mecca, Jerusalem. The direction of the city where a friend, an affection, a love live 32. how many hours are missing at sunset 33. how many hours of light remain (until the Civil Twilight) (usable in places of outdoor recreation) 34. how many hours before the sky will be completely dark (Astronomical twilight) (for amateurs) 35. how many hours have passed since dawn (Babylonian hours) 36. the Temporary hours that ancients used and that we find in the Gospels 37. the length of the day (period of light) 38. The days of the year in which the day has a fixed duration 39. the zodiac sign of the day (for astrology enthusiasts) 40. the day of the year - the beginning of the months 41. a particular date - anniversary, holiday, patron saint, Christmas, Advent 42. periods of the year - beginning and end of the school, tourist seasons, opening of a hotel 43. when noon will be in distant cities. Geographical or universal sundials 44. special hours. Hours of Islamic prayers, opening hours of a shop, school hours, etc.
Best Gianni Ferrari <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> Mail priva di virus. www.avast.com <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> 2018-01-15 16:13 GMT+01:00 Jos Kint <[email protected]>: > > With a sun dial you can measure at least 24 astronomic, religious and > other parameters: 1. The time of the day; 2. The day of the year; 3 and 4: > The geographic coordinates longitude and latitude of the sundial; 5. The > time equation; 6. The moment of the vernal equinox; 7. The moment of the > autumn equinox; 8. The moment of the summer solstitium; 9. the moment of > the winter solstitium; 10. the moment of the perihelion; 11. the moment of > the aphelion; 12. The excentricity of the earth orbital around the sun; 13. > The length of the tropical year; 14. The latitude of the tropics; 15. The > altitude of the sun at each moment; 16. The azimuth of the sun at each > moment; 17.The moment of sun set; 18. the moment of the sun rise; 19. the > length of the spring, the summer, the autumn and the winter; 20. the > babylonic time; 21. the Italian time; 22. The canonic moments (the vespers, > the matins,) 23. The moment of the islamic prayers; 24. The analemma of 12 > hours. > > The precision of these paramerters depend on the size and the structure of > the sundial and the number of observations, eg. the excentricity of the > earth orbital around the sun ( at this moment e = 0.0167) can be measured > with a simple sundial with an error of less than 1%. You just need much > patience... Sometimes it takes several hunderd measurements ( = some years > of daily observations). > > > Jos Kint > De Pinte, Belgium > > > *From:* Thibaud Taudin Chabot > *Sent:* Monday, January 15, 2018 12:19 PM > *To:* Sundial sundiallist > *Subject:* Re: The utility of sundials today. > > A sundial is a timing device entirely driven by solar power and has an > automatic and precise reset after powerfailure....... ;-) > > At 20:26 14-1-2018, Willy Leenders wrote: > > When I talk about sundials, I get the question: "What utility can sundials > have today?" > In order to be able to give an answer as diverse as possible, I would like > to receive your answer to this question > > > Willy Leenders > Hasselt in Flanders (Belgium) > > Visit my website about the sundials in the province of Limburg (Flanders) > with a section 'worth knowing about sundials' (mostly in Dutch): > http://www.wijzerweb.be > > > > > > > > --------------------------------------------------- > https://lists.uni-koeln.de/mailman/listinfo/sundial > > ------------------------------ > Th. Taudin Chabot, . [email protected] > > > > ------------------------------ > --------------------------------------------------- > https://lists.uni-koeln.de/mailman/listinfo/sundial > > > --------------------------------------------------- > https://lists.uni-koeln.de/mailman/listinfo/sundial > > >
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