Do rainbows touch the ground? Truly, rainbows are fascinating and magical, but they can also be a confusing phenomenon.
When you look at a rainbow, you only see the classic semi-circular rainbow.
And it often makes people wonder and ask, “do rainbows actually touch the ground?”
Apparently, it seems that if you move along, you might be able to see where it touches the ground. But is it really possible?
Unfortunately, rainbows do not touch the ground and you cannot get to the end of a rainbow, as it is more of an optical illusion and moves as you move.
Fact: Several antique artworks depict the Greek goddess Iris as a rainbow.
More about Rainbows
A rainbow is an arc of colors produced by light passing through water droplets suspended in the air.
The colors always form the rainbow in the order of their wavelengths.
For instance:
- Red has the longest wavelength
- Violet has the shortest wavelength
- Green, yellow, orange, and blue come in between red and violet
Less than an hour is the typical lifespan of a rainbow.
On the other hand, in 2017, a rainbow was visible from the highlands above Taipei, Taiwan, for as long as nine hours.
Sheffield, England in 1994 saw the longest-lasting rainbow before this one.
According to the Guinness Book of World Records, the duration of that rainbow was somewhere around six hours.
Do Rainbows Touch The Ground?
Rainbows are an optical illusion.
It means they don’t exist at any one particular spot and each observer will see the rainbow differently depending on where they are in relation to the horizon.
The midpoint of a rainbow, called the antisolar point, is always exactly opposite the sun which needs to be behind the observer for the rainbow to be seen.
From a distance, the ends look as if they will be touching the ground however they do not.
More about the Shape of the Rainbow
The real shape of a rainbow is a circle, but to the ground-level observer only the arc above their horizon can be seen.
The rest is hidden from view by the horizon.
Another observer watching from a different position will see a different-looking rainbow along with what appears as a different location for its ends.
If either observer moves, the ends will too, so they will never reach the end of the rainbow or find the mythical pot of gold buried there.
Both observers need the light to enter their eyes at just the right angle to see any rainbow at all.
Since each person’s horizon is slightly different no one ever sees the full circle of a rainbow from the ground.
Fact: The gas storms on Jupiter are persistent, and there may be frozen water on Mars, but only Earth in our solar system can produce rainbows.
Visual Perception of Rainbows
Does a rainbow touch the ground? Not really! We see rainbows because of the geometry of raindrops.
When the sun shines into the rain from behind an observer, light enters each drop and is refracted inwards.
It is then reflected from the back surface, and refracted again as it exits to return to our eyes.
The light enters hitting specialized photoreceptors in the retina.
The receptors turn light into electrical pulses that are passed to the brain by the optic nerve.
In the brain, perception takes over as the brain transforms the signals into images based on information from the other senses and memory.
The Magic of Rainbows
Rainbows form as a result of an interaction between light, water and air.
They are visual illusions, a literal trick of the light, with the interplay between light, water and air happening high in the atmosphere.
By seeing it we have processed the light correctly but it is a stimulus without substance.
We can see it but can never find the end of it and touch it.
Fact: In the case of a double rainbow, the light gets reflected twice in the raindrop, creating two separate reflections that appear to be originating from different directions.
Different Rainbows for Everyone
The light illusion the interaction between water, air and light produces doesn’t even produce a bow, but a halo high up in the atmosphere.
The rainbow we see isn’t where it looks to be, and it never touches the ground.
Even if you thought you knew for sure where a rainbow’s end touched the earth, to someone already there the rainbow you saw would never have happened.
The Illusion is Real
Rainbows are an optical illusion we perceive as always just ahead of us.
A rainbow will remain visible as long as there are water droplets and the sun is shining through them from behind you.
If the sunlight is lost or the rain stops, the rainbow disappears.
And from where you are, you can no longer see it although someone standing somewhere else perhaps can.
In other words, the illusion disappears from your perspective as you shift position making the way you saw that rainbow unique to you.
The Effect of Refraction and Angle of Observation on Rainbows
In the right conditions such as after rainfall, many droplets of water remain suspended in the air, but this on its own does not guarantee a rainbow.
It takes a beam of sunlight hitting the individual droplets from one direction.
This allows for a process called refraction to take place.
Understanding More about Refraction
Refraction is the redirecting of a wave as it passes through a denser medium, in this case, sunlight through a drop of water.
The end result is the light exiting the drop as separate colors of the spectrum.
Sunlight is white light that is made up of many different wavelengths, including colors.
The longer wavelengths are the reds, meaning their way from the sun to the earth. The shorter wavelengths, blue and violet travel faster.
Effects of Refraction
The refraction process creates a halo of color.
A phenomenon that can only be seen in its entirety if you are observing from above.
They can happen wherever droplets form, near waterfalls or on foggy days; all they need is a light source to catch them.
So there are other kinds of rainbows besides those that refract light into color wavelengths.
We see the color spectrum when light passes through the droplets at different angles, about two degrees each wavelength going from red to violet.
Some of the light is scattered and the edges of the bands blur. This angle of scatter is a variable dependent on the position of the observer.
Understanding More about Angle of Observation
Suspended raindrops are only approximately spherical.
It means when light meets a drop, the angle the color wavelengths are refracted and forced out can be more chaotic than that of a prism.
However, this angle of observation is still constant.
The wavelengths for a true rainbow always exit at a droplet angle of 42 degrees .
Therefore, an observer can only see the colors of the returning light when their eyes are positioned at 42 degrees.
Effects of Changing Angles
From certain other angles, rainbows seem to form and give the illusion they are touching the ground.
But, these reflections are also tricks of light, the effect created when light enters the droplets from differing angles.
The light is scattered but when a strong ray of sunlight manages to enter a droplet dead center it is inverted and reflected back on itself.
It bounces out on the same pathway it came in but with the wavelengths opposite and appear as a mirror image of the rainbow, a double rainbow.
Other rainbows with multiple images appear across the sky like the archways of a bridge.
Fact: Since snow inhibits light from dispersing and refracting into different hues, rainbows are rare in the winter.
Takeaway
Do rainbows touch the ground? Light creates rainbows when it passes through water droplets in the air and is refracted, reflected, and scattered.
You can see them as a ring of color in the sky, with red on the outside and violet on the inside.
Despite their seeming end at the earth, rainbows do not touch the ground.
And in reality, the location of the observer determines the apparent base of the rainbow.
From a very high vantage point, like an airplane or a mountaintop, it is possible to see the entire circle of rainbow colors.
But, even then, the rainbow does not reach the ground in any of these cases.
