Here's a quick one for all you lovers of the colour magenta (including pinks and purples). In reality it, the colour does not exist. Unlike all other colours of the visible light spectrum, or electromagnetic radiation there is no wavelength of light that corresponds with magenta - hence the reason it's not in a rainbow. It appears that this colour is made up in the software that runs the organ we call our brain. The reason it does this is because magenta falls between red light and blue light and is really the absence of green - our brain does this to cope.
Look at this minute physics lecture on youtube it explains it really well
While on this sort of subject I have really been getting into the minute physics lectures along with many from the Royal Institution and listening to the infinite monkey cage hosted by the it's amazing Brian Cox.
Finally here's a thought about the Voyager space probes that have now left our solar system and the suns influence. As they travel on their interstellar journey think about the gold plaques on their side - these are there as an introduction to mankind, but maybe more importantly to give hope to humanity. The whole venture was the work of Carl Sagan. If you think how insignificant these space craft are, that they are unlikely to ever be found by any species - since they are so tiny in the Universe - and yet they will outlast humanity and will one day be the only evidence we ever existed.
