Circumzenithal arc

The skunk will have to wait.

Last evening I managed to take the first good picture of a foraging skunk in a long time. I was about to post it, when a circumzenithal arc appeared in the sky. Nature’s palette is rich; the skunk got skunked.

The circumzenithal arc has been featured on these pages a few times before:  Feb. 27, 2011 and Dec. 25, 2012. I am a sucker for its beauty, which can outdo a rainbow. The arc appears high in the sky (circumzenithal: it circles the zenith) when the Sun is low. It has a brother: the circumhorizontal arc (it circles the horizon) appears low in the sky when the Sun is high. The occasions when one can see the circumhorizontal arc were discussed recently as blue cirrus. I will continue to watch for the circumhorizontal around midday all this month.

A fisheye picture shows the circumzenithal arc as a coloured line high in the sky. The Sun is behind the trees, but has an elevation of about 18°. The curvature of the horizon is a consequence of the fisheye lens.

As patches of cirrus drifted through the requisit position, the arc would appear and disappear. By the time this more detailed shot was taken of the arc itself, the Sun had climbed to 20°. It shows a superb spectral range.