The Power of the Sun

Thoughts about the physical source of natural light, which we take for granted every day, fill us with awe. Born in the core of the sun, under 200 billion bar pressure, the ray of photons fights its way through the fusion reactor of our central star. Although the photon moves at the speed of light, it takes an incredibly long time to reach us. Again and again it is reflected and scattered by the densely packed particles of the solar plasma. Once the light has reached the surface of the sun, it moves out into space almost unchecked. For the almost 700,000 km distance from the sun, the light takes several ten thousand years and loses enormous amounts of energy. This energy loss causes the shift of the wave spectrum to a range observable for us. The last 150 million kilometres to Earth are then covered by light in 8.3 minutes.

The light that reaches us at this very moment was born at a time when mankind was just beginning to tame fire. It is all the more impressive how, in this context, a wafer-thin and almost void cloud in the sky can influence our emotional state so strongly. This illustrates all the more how our eyes are perfectly tuned to the light available to us. The spectrum visible to all of us from ultraviolet to infrared light results from a thousands of years of evolutionary adaptation to our needs that also allows us to distinguish even the smallest changes in wavelengths.