If you are living in some remote village, then you must have experienced this something that I call fake sunrise or fake sunset.

While the sun has completely set in the west, look at the far east at horizon. You’ll see light and sun rays progressing vertically upwards in the far east. This is called fake sunset.

Similarly, while the sun is about to rise in the early morning in the east, look at the far west at horizon. At far east you’ll see light and sun rays in the sky. It apparently seems as if the sun is about to rise from the west. This is called fake sunrise.

Fake Sunset due to Anticrepuscular Rays at Florida Gulf Coast USA

Fake Sunset due to Anticrepuscular Rays at Florida Gulf Coast USA

The above picture is taken at very early morning before sunrise. This photograph is taken by camera pointing at west and not at east, as you will usually assume. Are you surprise, how come so?

Here, I will explain the physics behind fake sunrise and fake sunset. Look at the self explaining picture below that I have made. Sorry, for the so childlike drawing. 🙂

Physics of Fake Sunset or Fake Sunrise

Physics of Fake Sunset or Fake Sunrise

There are two types of visible sun rays. They are crepuscular rays and anticrepuscular rays. Both are seen passing through the clouds due to dust and water vapors present in the air.

Crepuscular Rays

Crepuscular Rays

Crepuscular Rays

Crepuscular rays are seen in the same direction as location of the sun. They can be spotted frequently on a cloudy sky during anytime of the day. Crepuscular Rays


Anticrepuscular Rays

Anticrepuscular Rays

Anticrepuscular Rays


Anticrepuscular rays are seen less frequently and only during early morning or late evening. They can be spotted in the opposite direction of the location of the sun.

Fake sunrise and fake sunset are the result of anticrepuscular rays. They look amazing.