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.

On rare occasions, two rainbows form at the same time. The first and brighter rainbow is called the primary rainbow. The second less vivid one is called the secondary rainbow.

The rainbow is curved because the set of all the raindrops that have the right angle between the observer, the drop, and the Sun, lie on a cone pointing at the sun with the observer at the tip.

If we draw rays of sunlight that reflect at 42 degrees into your eyes then those rays start to look like they form a circular arc in the sky. So the reflection gives you the shape of the rainbow, while the refraction gives you the colours of the rainbow. From the air you can see circular rainbows.

Flat rainbows are more commonly known as ‘fire rainbows’. They get the name because of their incredible bright colours and flame-like outline. They are most commonly formed when cirrus clouds are far enough up in the air to form plate-shaped ice crystals.

Iridescent clouds, known as “fire rainbows” or “rainbow clouds,” occur when sunlight diffracts off water droplets in the atmosphere. And sometimes moisture in that air suddenly condenses into tiny droplets to form a cap cloud.” This “cap”—which scientists call a “pileus”—is the source of the brilliant spectacle.

While fire rainbows are relatively common throughout the United States, they are rare in northern Europe for several reasons. Not only do the ice crystal-containing clouds need to be in the right position in the sky, the halo requires the light source must be at an elevation of 58 degrees or higher.

circumhorizontal arc

Janet Pierucci noticed this gorgeous site, a vertical rainbow, also called a Sun Dog or a Parhelion. A Sun Dog is a rainbow in the sky but there are no rain clouds. The ice crystals in the clouds act as prisms and, if conditions are right, you get this rare phenomenon.

Did you notice a rainbow ring around the sun today? It is called a halo and these are very common when we have high cirrus clouds in the atmosphere. The light is bent as it moves through the ice creating the atmospheric optical display known as halos!

The optical phenomenon only happens when the sun is higher than 58° above the horizon and its light passes through high-up cirrus clouds made up of plate-shaped ice crystals, according to the University of California geography department. Despite its common name “fire rainbow,” the phenomenon is not a rainbow nor fire.

it’s possible that it was actually raining without reaching the ground. All we need for a rainbow is sun going through some form of water, even if that doesn’t always reach the ground… All we need for a rainbow is sun going through some form of water, even if that doesn’t always reach the ground.

Bottom line: You might on occasion see a rainbow-like cloud. They’re fairly rare, but people do spot them, and we sometimes receive photos of them. They’re caused by the presence of very tiny ice crystals or water droplets in the air, which cause light to be diffracted (spread out). The 2019 lunar calendars are here!

What is at the end of the rainbow? At the end of the rainbow is a pot of gold.

You’ll never swim out to the horizon , and you’ll never reach a rainbow’s end. The visibility of both requires distance between object and observer. Rainbows consist of water droplets being struck by sunlight in a certain way.

I have set my rainbow in the clouds, and it will be the sign of the covenant between me and the earth. I will remember my covenant between me and you and all living creatures of every kind. Never again will the waters become a flood to destroy all life.

six hours

honeymoon phase

A halo seen around the moon. The halos you see are caused by refraction, or splitting of light. Moon halos occur when there are high, thin clouds across the sky. The clouds are filled with countless ice crystals, each of which is shaped like a tiny hexagon.

When visible around the Moon, it is called a moon ring or winter halo. It forms as direct sunlight or moonlight is refracted in millions of hexagonal ice crystals suspended in the atmosphere. The halo appears large; its radius is roughly the length of an outstretched hand at arm’s length.

The phenomenon is quite rare, as the ice crystals have to positioned exactly right in relation to where you are looking up in order for the halo to appear. It’s not that rare – people are just rarely looking up at the sky when it appears.

When thin clouds scud across a bright moon it is often surrounded by a bright disk and faint coloured rings, a lunar corona. Sometimes as clouds pass over the moon the corona shrinks and swells as different sized droplets mould it. Small droplets make the largest coronae with aureoles a few moon diameters across.