You see a semicircular rainbow only because the ground is in the way look out of the window next time you re in a plane you might see a full circular one around the shadow of your plane on the clouds

You see a semicircular rainbow only because the ground is in the way. Look out of the window next time you’re in a plane – you might see a full circular one around the shadow of your plane on the clouds.

Rainbows have always fascinated humans with their vibrant colors and mystical appearance. Most of us have seen the typical arch-shaped rainbow after a rain shower, but did you know that there is also a full circular rainbow that can be observed from certain vantage points?

The reason we usually see a semicircular rainbow is due to the interference of the ground. Imagine yourself standing in an open field with scattered raindrops in the air. When sunlight enters these raindrops, it undergoes refraction and separates into its constituent colors. This bending of light causes the formation of a rainbow.

Typically, a person standing on the ground observes a semicircular rainbow because the earth’s surface obstructs the bottom half. As a result, only the top half of the rainbow is visible to the viewer. However, there is a special scenario that allows for the observation of a full circular rainbow.

Next time you find yourself traveling above the clouds in an airplane, take a moment to look out of the window. You might get the opportunity to witness a breathtaking phenomenon – a full circular rainbow surrounding the shadow of your plane on the clouds.

When you are in an aircraft, your viewing angle changes, and you are positioned above the ground. This change in perspective allows you to observe the entire circle of a rainbow. As the airplane casts a shadow on the clouds below, sunlight refracts and reflects within raindrops, resulting in a circular ring of colors around the shadow’s perimeter.

The circular rainbow visible from an airplane offers a unique and mesmerizing experience. It serves as a reminder of the beauty and complexity of nature’s optical phenomena. So, the next time you fly, remember to look out of the window and keep an eye out for this majestic celestial display.

Sources:

• Quora: Can you ever see a complete circle rainbow?