Today's interesting fact has to do with the Northern Lights.

The Northern lights or Aurora Borealis is a natural light display that often appears in the Artic and Antarctic

The lights are caused when high speed particles, usually from the sun, hit the magnetic field of the earth.

I mention it today, as there has been a coronal mass ejection (CME) that has hit the Earth, and the effects will be noticed for the next couple days.

This also means that the Northern Lights are likely to be seen as far south as was seen in 2005, the last CME that was similar in size to this present one.

Then, the Aurora Borealis was seen as far south as the Caribbean.

Today’s interesting fact has to do with light from the sun and why certain disaster movies make no sense.

We live on the earth courtesy of the light and heat we receive from the sun.

There have been several disaster movies about the sun shutting down, and that life giving light stopping.

The light that comes from the sun is generated by several means.

One source is the ionised atoms in the outer shell of the Sun.

Interactions between these ions generate photons, which escape the sun providing light.

Another source is the atomic furnace deep within the sun. Hydrogen atoms fuse and the result generates heat and light.

The heat creates the gigantic convection currents that roll through the sun, spreading the heat and creating the ionised atoms that generates some of our light.

The photons generated from fusion travels in a random direction. We are told that in general it will travel at the speed of light on average about 2 cm before it gets absorbed by another atom.

The atom that absorbs the photon will then release a photon, in a random direction only to be absorbed by another atom.

It is estimated that it will take about a million years before the average photon created by fusion leaves the surface of the sun.

In the disaster movies, fusion stops, the sun stops shining, and intrepid astronauts go to the sun, and using our nuclear weapons, restart the sun.

But if the sun stopped fusion, it would take a million years before it started to dim so I doubt we would notice the process had stopped.

And if we restarted the sun's fusion, it could take a million years before it started to shine at the same levels as it does now.

So those movies are not based on facts, and we can stop worrying about the sun going out.

Today’s interesting fact has to do with lenses.

The purpose of a lens is to focus light.

Children often learn about this is science classes, but before that many children learn to burn holes in cardboard, leaves and wood.

The average lens children play with to burn things focus light up to 1000 times.

The lens of your eye is better at focusing light, and is 2.5 times more effective.

Because the lens of the eye focuses mainly on the fovea, this is why they tell you to not look at the sun.