The sun is the source of life on this world, yet at the same time it can be very dangerous for us and other lifeforms on earth. The life giving energy that is emitted from the sun to earth's surface needs to be made use of through processes like photosynthesis, but it also needs to be "disarmed" or filtered. This episode is the first part of a two-part series that looks how we protect ourselves from the sun. We start of with oftentimes mentioned ozone layer, the first line of defense.