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Vallvidrera - el Tibidabo i les Planes, Barcelona, Spain

Latitude: 41° 25' 6'' N

Longitude: 2° 7' 27'' E

25 October 2015 0820 (Local Time)
Camera direction: towards E

Image P/S code: P.13.1.4

Image I.D.: 5442

22° halo and upper tangent arc
“Tangent arc” is the generic term for several types of luminous arcs that form tangentially to other halos. In this picture, a tangent arc touches a 22° halo at its highest point, and therefore is an upper tangent arc.

Tangent arcs have a form that varies with the angular elevation of the light source (the Sun or Moon). When the light source is just above the horizon, the upper tangent arc takes the form of a narrow V-shape. As the Sun or Moon rises in the sky, the V-shape of the upper tangent arc opens to a shape resembling the outstretched wings of a large bird.
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© Alfons Puertas
Vallvidrera - el Tibidabo i les Planes, Barcelona, Spain
Latitude: 41° 25' 6'' N
Longitude: 2° 7' 27'' E
25 October 2015 0820 (Local Time)

Camera direction: towards E
Image P/S code: P.13.1.4
Image I.D.: 5442
Halo display
This extreme wide-angle photograph from Antarctica shows a 22° halo with two parhelia, or sun dogs, at 2 and 3 on either side. Circling the horizon and lying horizontally through the parhelia and the Sun is the parhelic circle at 4 and 5. At the top and bottom of the 22° halo are an upper tangent arc and a lower tangent arc, which extend around the 22° halo as a faint luminous curve to meet each other and form a circumscribed halo.
Links in the image description will highlight features on the image. Mouse over the features for more detail.
© Tatsuru Fujita
1-1 Ichibachō, Chūō-ku, Chiba-shi, Chiba-ken 260-0855, Japan
Latitude: 77° 19' 12'' S
Longitude: 39° 42' 0'' E
24 December 2004 1328 (Local Time)

Camera direction: towards NE
Image P/S code: S.13.1.1 6
Image I.D.: 4796

22° halo and upper tangent arc

Halo display