RE: Re: Double analemma dials

C Sent from XFINITY Connect Mobile App -Original Message- From: jlcarmich...@comcast.net To: sundial@uni-koeln.de Cc: Sent: 2016-08-17 3:45:40 PM Subject: RE: Re: gn to use- especially children. I've seen that even dialists get confused too. So when I was asked to redesign and insta

Sombrero as a sundial

This sombrero is a reminder that we should all wear sundial hats to our next meetings. 20 points for the heaviest version. 50 for wearing it on the plane. I am sure that someone has perfected the idea into time readable fashion. A modified version with a "wakeup hole" to let the sunlight through t

RE: Re: Double analemma dials

Whenever I include analemmas on sundials, no matter how well I try to explain their function, people always get confused and find them difficult to use- especially children. I've seen that even dialists get confused too. So when I was asked to redesign and install a replacement dial for the flawe

Re: Double analemma dials

To all sundialists, I cannot refrain from inverting Willy's statement. I would say 'Tell the people that sundialsgain or lose compared to the time which governs the universal laws of physics'. /Solar/ time (indicated by whatever type of sundial) maps time differently and unevenly depending onth

Re: Sunsweep sculpture

Thanks to Dave and Roger for replies to my inquiry about the Sunsweep sculpture. I understand that equinocial sunrise and sunset occur due East and West and I can live with Dave's suggestion of inferring North by imagining a perpendicular to the plane of the sculpture. That still leaves me

Re: Re: Double analemma dials

In message "fabio.savian" wrote: > > I know an analemmatic sundial may have sophisticated versions to show > mean time, Fred your article is exhaustive, but I think it isn't the > better kind of sundial to give this info and to get a precison time > (position on the heels or on the mi

Re: R: Re: Double analemma dials

To all sundialists, All that stuff is the result of the irresistible urge to let indicate the time of a watch by a sundial. A sundial is intended to indicate the solar time. It is the only simple instrument that can do it. In order to indicate the artificial time, which we have created to practi

R: Re: Double analemma dials

thank you Willy and Fred for your notes, I know an analemmatic sundial may have sophisticated versions to show mean time, Fred your article is exhaustive, but I think it isn't the better kind of sundial to give this info and to get a precison time (position on the heels or on the middle of the

Re: A Strange Rainbow

Dear Jackie, Rather more common are mock suns, or sun-dogs, which are either side of the sun. Some dramatic examples are in: https://en.wikipedia.org/wiki/Sun_dogs They are at 22º either side of the sun, and if you know when and where to look, and in t

Re: A Strange Rainbow

Would this be the same as a 'Sun Dog'? On 2016-08-17 10:36, Dave Bell wrote: Typically, this would indicate ice crystals in the upper atmosphere. A normal rainbow is formed by water droplets with two internal reflections, so the rainbow's light is projected back towards the sun. In this case,

Double analemma dials

Hi Folk I thank Fred Sawyer for his note on the direct reading mean time double analemma dials and will be pleased to provide a note on their construction to anyone interested. Their average error is about 30 seconds; maximum error about 3 minutes. These dials are quite different from the in

Re: A Strange Rainbow

Hi Jackie, I think that what you have there is a circumzenithal arc (CZA), possibly with a matching circumhorizontal arc (CHA). They are caused by the sun's rays refracting through ice platelets high in the atmosphere. You need the sun low in the sky for them to be seen. There are other ice halo

Re: A Strange Rainbow

It’s called a circumzenithal arc. Unlike a normal rainbow, which is caused by total internal refraction within a (or, rather, millions of) water droplets, circumzenithal arcs are caused by light scattering in ice crystals in the upper atmosphere. They are generally only visible on very clear da

Re: A Strange Rainbow

Typically, this would indicate ice crystals in the upper atmosphere. A normal rainbow is formed by water droplets with two internal reflections, so the rainbow's light is projected back towards the sun. In this case, the light is passed forward through the crystals, at an angle determined by the