Peter explains where the sand on our beaches comes from, why it is sometimes fine and sometimes coarse and why the colors of the sand can vary on beaches around the world.
Videoclip: Planetopia – Woher kommt der Sand am Meer?
Videoclip: Planetopia – Woher kommt der Sand am Meer?
Videoclip: Planetopia – Warum sehen wir unter Wasser unscharf?