A fraction of a halo arc can be noticed in the Cirrus clouds at Ingelheim in the late afternoon, whereas a whole circumsolar arc is pictured in the two images taken in Brazil. In the third image of Lagua do Banana a Cumulus pannus cloud has moved in between of the halo and the observer and largely covered it. In Halo7.jpg the halo was likely formed at Cirrus clouds which derived from aged contrails of an aircraft.

Halo1.jpg: J. Engel, S. Borrmann, Ingelheim, Germany, 14 July 2002, 7:50 p.m. local time

Halo2.jpg, Halo4.jpg and Halo6.jpg: S. Borrmann, Lagua do Banana near Fortaleza, Ceara, Brazil, 29 February 2004, 10:23 a.m. to 10:26 a.m.

Halo7.jpg: L. Göring, Mainz-Kostheim, Germany, 24 April 2004, 8:30 a.m.

Camera Parameters

Olympus E-1 SLR with 14-54 mm objective. Exposure and Selectivity choice (100 ASA) was performed by camera automation. The images were taken in the sRGB colour range with a resolution of 2560 x 1920 Pixel x 24 colours.