This is an exceptional picture of the moon. Because it is made with a solar telescope!
The difficulty lies in the fact that in a solar telescope something like 99,97% of the light of the object you are studying is blocked. Otherwise the camera can burn. This blocking of the light is not a problem when you look at the sun which is a very bright object. The moon is different as it doesn't produce any light. The moon just reflects sunlight.
So, Emil Kraaikamp - the person who made this picture and works at the STCE - used an exposure time of 5 seconds for each picture in a series of 50 contrary to the exposure time in the order of milliseconds for solar pictures. He also had to increase the gain (=brightness magnification) of the camera, resulting in noisy images. In those 5 seconds, things are changing. The moon moves a little bit in the firmament and the telescope is not able to perfectly follow the moon. This makes a big difference and results in a blurry picture.
By stacking 50 of these pictures with the 50 moons on top of each other, Emil was able to avoid most of this blurring and at the same time get rid of the noise.
Enjoy this amazing picture!
