Algodoo

for Mariofan5's MasterColorChef

At the end of the rainbow, there is another half circle of rainbow.
Rainbows are actually prototypes. That is, there is an endless, turned rainbow. However, because it is reflected on the ground, we can only see the half circle in our eyes and do not recognize it as a circle. From an airplane, it looks circular, proving that a rainbow is a circle.