Product: Portable ring sundial with display of solar time (WOZ). Solar compass and navigator. For all latitudes, including the southern hemisphere.
Display: True local time (solar time) Material: Meridian ring and date ring are made of stainless steel, all scales and the time ring are made of aluminium with scratch-resistant sub-anodised printing. The shiny parts are palladium-plated.
Dimensions: D= 96 mm x H= 138 mm x D= 5 mm (folded) Weight: 110g
The CIELO is supplied in a jewellery box with a detailed manual.
Animation Cielo sundial (pocket sundial)
CIELO ring sundial
The versatile sundial. Can be used as a solar compass - solar chronometer - navigator
The period from the 16th to the 18th century was the heyday of sundials. Mechanical clocks were still too inaccurate and too expensive for the majority of people. The official time of civic life was local time as measured by sundials. The queen of all sundials at that time was the ring sundial. The standard design has hardly changed since the middle of the 17th century: A pinhole aperture is set according to the date and the point of light, projected by the sunlight, is then used to orientate the clock in a north-south direction and display the time.
Learn about the connection between the sun's migration and the measurement of time
This portable sundial finds the north direction without a compass and can be used for all latitudes in the world. In every country on earth, and only by sunlight, it can be orientated to north and thus becomes a fully-fledged compass. It is a model of the celestial sphere and allows us to understand the origin of time measurement from a cosmic perspective. In addition, it makes us aware of the connection between the movement of the sun and the measurement of time.
Once orientated to the north, the north pointer of the CIELO points to Polaris. If you mentally project the equatorial ring onto the sky, you will find the celestial equator there. The sun, moon, planets and stars appear to move along this imaginary circle in the sky. The movement of the sun, as a measure of our time measurement, is visible through the shadow on the equatorial ring.
The time of day can be read directly from the time scale. This time is the true local time for your own location. The zone time valid in the country (CET in Central Europe) is a time devised by man for measurement on mechanical clocks, which does not correspond to the true local time, but can be calculated.
The reverse of the date scale shows the current value of the equation of time: a value that is needed to calculate the zone time from the true local time
The CIELO, Italian for sky, is the optima forma of ring sundials. More accurate than its historical model and easier to operate.
The most important innovations are:
- The north-south alignment of the historical ring sundial is difficult, as the point of light required for adjustment is not visible at first. Only by trying and readjusting the pinhole aperture several times is it possible to make the point of light inside the equatorial ring visible. The CIELO has a shadow caster with a sun sphere, which casts a shadow that is always visible regardless of direction, making north-south alignment much easier. This is achieved when the shadow of the sphere is in the centre of the inside of the equatorial ring
- The conventional light dot does not fall directly on the time scale. On the CIELO, the time can be read directly from the shadow line.
- The densely packed, linear date setting of the historic ring sundial has been replaced by a circular date scale spread over 360°, which allows the solar sphere to be set sensitively and precisely even at the solstices.
- The latitude scale extends from the horizon to the zenith so that it corresponds to the elevation angle of the celestial pole (pole height). This angle is also measured in seafaring with the sextant and corresponds exactly to the observation at the location.
|Ø 96 mm, H= 138 mm, D= 5 mm (folded)
|True local time (solar time)
|Made in Germany