Mountains on the moon during solar eclipse? I ask myself the reason of why the sun in not uniform on the edge of the moon at this moment of the eclipse (cf. picture) is not unifom is because of the mountains of the moon ? Or can it due to erruptions of sun ? If not is there another reason to explain that ?
The beads of bright light can be seen thanks to the Moons rugged topography. They're called Baily's beads in honor of an English astronomer who explained the phenomenon, Francis Baily.

In the photograph you posted, you can also see Solar prominences. It's plasma ejected into the corona. Its temperature is lower than that of the coronal plasma and it emits more visible light.