The rainbow is curved as it reflects the round shape of the sun. ... Rainbows are circular because raindrops are spherical. When light from the Sun enters a raindrop it is largely reflected back inside a cone with a half-angle of 42 degrees.

Is a rainbow really a full circle?

Rainbows are actually full circles. The antisolar point is the center of the circle. Viewers in aircraft can sometimes see these circular rainbows. Viewers on the ground can only see the light reflected by raindrops above the horizon.

Why are double rainbows inverted?

When there is a double rainbow, the color order is reversed. ... Double rainbows happen when the light gets reflected twice inside the water droplet. It's a reflection of the reflection. So technically, the first bow shows the color pattern backwards and the second reflection corrects the pattern.