Friday, April 7, 2017
Plane contrail and sun halo - NATURAL PHENOMENA
What happened to the sky? Several common features of the daytime sky are interacting in a uncommon ways. First, well behind the silhouetted hills, is the typically bright sun. In front of the sun are thin clouds, possibly the home to a layer of hexagonal ice crystals that together are creating the 22 degree halo of light surrounding the sun.
The unusual bent line that crosses the image is a contrail - a type of cloud created by passing airplane. Much of the contrail must actually be further away than the thin cloud because it casts a shadow onto the cloud, giving an unusual three-dimensional quality to the featured image. The featured image was taken in late January in the city of Patras in West Greece.
Image and info via APODhttps://apod.nasa.gov/apod/astropix.html
Image credit & copyright: Alexandros Maragos