(Intro music playing)
Lots of things get mistaken for UFOs
Sometimes, it's a frisbee
Sometimes it's the planet Venus
Sometimes it's a military missile and sometimes what looks like a UFO might even be the effects of the Sun.
Sunlight can make all sorts of optical illusions: from big pillars that look like abduction beams, to huge halos in the sky.
And most of these optical illusions happen for similar reasons.
Because of the way sunlight interacts with small ice crystals in the atmosphere
And if it's really cold, there can even be a whole cloud of ice crystals
which is kind of an optical illusion all by itself.
It's sometimes called Diamond Dust because it looks like a sparkling cloud.
The sparkling comes from the ice crystals reflecting and refracting the light that hits them.
Light that bounces off the crystals is reflected
and light that goes through the crystals and gets bent along the way is refracted.
This reflection and refraction can also lead to other optical illusions
depending on the size, orientation, and location of the ice crystals.
The most common illusion is the Sun Halo
or more specifically : The 22 degrees Sun Halo.
Which gets its name because the halo is almost always seen 22 degrees offset from the Sun.
That's a little less than the distance from the tip of your thumb to your pinky
if you stretch your hand out at arm's length with your fingers spread out.
Twenty-two degrees might seem like kind of a random number, but it has to do with the property of ice called its refractive index.
That refractive index means the light bends at a certain angle when it enters the ice
And then it bends again when it leaves the ice.
The total effect is about a 22 degree bend
Though the angle changes slightly depending on the color of the light
and how the light hits the surface of the crystal.
If you have red light, for example, which has a longer wavelength
Then it won't bend quite as much as violet light, which has a shorter wavelength.
Sometimes these different angles make the halo look kind of like a rainbow around the sun.
The angle also depends on how the light hits the crystals' surface.
The crystals are arranged pretty randomly.
So some will refract light a little less than 22 degrees
And some will refract light a little more than 22 degrees
Which makes the halo look kind of thick and blurry
Sometimes though, the crystals do line up with one another.
And that's when you'll start to see an illusion known as Sun Dogs.
Which show up much lower in the sky.
Sun Dogs are a lot like Sun Halos, just much more intense.
Since most of the crystals are lined up in the same direction
You can see much brighter spots because they're all bending the light in the same way.
If the crystals are especially big they tend to be disturbed by the atmosphere a little bit more.
So they tilt and wobble.
This means that the crystals are at slightly different angles so there are more possibilities of how the light will hit the surface of the crystal.
They are still aligned enough to concentrate the light
but the Dogs will be bigger and blurrier.
Another optical illusion you might see is, A Sun PIllar
This one relies on reflection instead of refraction
and you normally see it around sunset.
Like with Sun Dogs, the ice crystals are arranged roughly horizontally in the sky
But this time they actually act like a giant mirror
that reflects the light from the sunset back down toward Earth
The crystals can be very large
Especially as it gets colder in the evening
And again like with the the Sun Dogs
These large crystals can become tilted at different angles
So they reflect light at different angles
You end up with a long column of reflected light.
A Sun Pillar
Sun Pillars might look kind of like sunbeams but,
So if you see rays of sunlight that seem to be shining from weird places
It's probably just the ice in the air.
One thing it's definitely not, is an alien abduction beam
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You know those pictures that your parents and your friends and your parents friends are always posting all over social media, the ones that have some sort of inspirational quote plus a picture where the sun seems like its using beams. *Fades out*