Sun dog

Nebensonnen or Parhelia (singular Parhelion, from Greek παρά pará - "next " and ήλιος hélios - "sun" ) are among the halos. You are at a distance of about 22 ° left or right, sometimes on both sides to see besides the sun. The observer here has the impression that it is located next to the sun, a second, weaker. In English they are called sun dogs ( sun dogs). This reflects the fact that Nebensonnen always be on the side of the sun and at the same level with her. A similar light phenomenon can also be observed at the moon. In addition to the moon can be seen, however, due to the lower light intensity rarely, usually only during a full moon.

Be Caused Nebensonnen like all halos by refraction and reflection of light by hexagonal ice crystals. For Nebensonnen this thin sheets of ice are responsible that align horizontally in still air. You ask for the sunlight a prism Represents the white sunlight enters this ice prisms one on one side and on the page after next again. The inlet and outlet, the light is refracted at an angle that depends on the wavelength. This gives the Sundog reminiscent of a rainbow gradient.

Much less common occur Nebensonnen located at a lateral distance of 120 ° from the sun on the horizontal circle. These appear to the observer as whitish spots. The she -causing beam path of the light through the ice crystals is different from the 22 ° Parhelia.

Artistic symbol

• The image of the sun dog was readily used in the literature of Goethe's time as an artistic symbol; particularly aware of the by Franz Schubert as the penultimate song of the cycle Winterreise, Op 89, set to music poems by Wilhelm Müller was the Parhelia ( " three suns in the sky I saw steh'n ...").
• Sundog Painting