While enjoying a spectacular sunset over Moscow many residents noticed something unusual going on on Ascension Day.
Light beams scattered by clouds in front of the setting Sun appeared to re-converge behind the horizon.
The striking photos of the unusual astronomical phenomena were spotted in the sky above Moscow on Ascension Day 2017.
After investigating, meteorological experts think the bizarre pathway was created by a combination of sunbeams ‘cast from over the horizon,’ clouds high in the sky and shadows.
Meteorologists have a technical term for this beautiful but rarely seen phenomenon: crepuscular rays.
The sun is dim but still shining on parts of the cloud high up, but the dark blue section is due to shadows being cast.
The shadows are most likely caused by clouds which can’t be seen from the observer’s point of view due to the curvature of the earth.
Although the Sun’s rays strike the Earth almost parallel to one another, we see them appear to come from a point because at a distance, parallel lines seem to converge, like railway lines disappearing over the horizon.
So-called crepuscular rays are the rays that appear when parallel solar beams are redirected through clouds and appear to diverge.
In this case, they were almost covering the entire sky.
Anticrepuscular beams appear at the other end of the sky from crepuscular beams. They converge on the horizon at exactly 180 degrees from the place where the beams appear to come from.
According to the pictures above, it is difficult to say if we are witnessing crepuscular or anti-crepusculars rays. Anti-crepuscular rays are not common, especially rare and dramatic examples like these.