Sweet Answer from Solar Mango: (updated Jul 2015)
(This answer is courtesy Suncyclopedia)
We all see sunlight, everyday.
Sunlight, is however, far more fascinating than what is apparent to us.
So, what exactly is sunlight?
Sunlight is made of energy carriers called photons.
Sunlight, like all light, is an electromagnetic radiation.
Now, who would have thought that that something as simple as light could actually be something as complex-sounding as “electromagnetic radiation”!
And what indeed is an electromagnetic radiation?
Well, put simplistically, electromagnetic radiation is a form of energy transmitted through space and other media. You could consider it to be a combination of electric and magnetic fields.
Light is a form of electromagnetic radiation, and carries energy in the form of photons.
Though it looks like a simple ray of light, sunlight, like many other forms of light, is in fact a spectrum. It has components with very short wavelengths (the ultraviolet rays) to components with relatively large wavelengths (infrared rays). Between the very small and the large wavelength portions lies the visible spectrum – the light we are able to see.
Wavelength is the length at which a wave’s shape repeats. In a crude way, you could say that different colors of light represents different wavelengths.
Adapted from http://webserver.as.arizona.edu/outreach/faq.html
All components of sunlight carry photons and hence are energy carriers, but all components of sunlight do not reach us. A large portion of the ultraviolet component of the sunlight is blocked by the atmosphere. Just as well, because exposure to UV rays can be quite harmful to us.
Sunlight is not just one type of light but comprises different “types”, each having photons at different energy levels.
Now, try looking at sunlight differently!
For a moment. forget the theoretical explanations given above and try visualizing it: Sun is about 150 million Kms from earth. A bunch of energy carrying photons start from a place so far away, and in just over 8 minutes, yes, just over 8 minutes, reach us humans to provide us with light, energy and life. Gadzillions of such photons leave the sun every second and make their quick journey to earth.
Close your eyes and imagine such a life-giving journey of sunlight for a few moments. Isn’t it a truly awesome feeling!
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