Sunshine autograph
Sunshine autograph , also called heliograph , is a simple measuring device for determining the duration of sunshine in a day.
functionality
It consists of a large glass ball that acts as a magnifying glass . A plastic or paper strip with time markings is attached to the spherical focal surface behind the sphere, in which the rays of light are maximally bundled . When the sun is shining, the sun burns point-like in the plastic or paper strips, resulting in focal lines over the course of the sun. The time stamp can then be used to determine exactly when and how long the sun was shining. To determine the duration of the day's sunshine, the lengths of the burned out lines are added.
The heliograph should not be confused with the pyrheliometer developed by the French physicist Claude Servais Mathias Pouillet , formerly also called pyroheliometer , literally: solar fire meter .
Footnotes
- ↑ Johannes Wilsing , Julius Scheiner : Determination of the temperature of 109 brighter stars from spectrophotometric observations . In: Astronomische Nachrichten, Vol. 183 (1909), Issue 7, Article No. 4375, pp. 97-108.
- ↑ Adolf Wolpert: Principles of ventilation and air heating. In addition to instructions for preventing smoking in the room stoves and cookers . CA Schwetschke and Son, Braunschweig 1860, p. 51.
Web links
- Museum of the Kremsmünster Observatory : Heliograph, sun recorder (with a detailed description of how it works), accessed on March 25, 2014.