whosebob
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The first thing to be noticed about the electromagnetic spectrum is how broad it is: the longest wavelength is 1025 times the size of the shortest one.
Written out in full, 1025 zero's looks like this:
10,000,000,000,000,000,000,000,000
A number that big is pretty meaningless by itself. Let's make a few comparisons. For example, in 4 billion years (the estimated age of the Earth) there are about 1017 seconds. If you wanted to count from 1 to 1025 and did so at the rate of one number a second nonstop, day and night, it would take you 100 million times longer than the age of the earth! If we were to build a pile of 1025 playing cards, we would end up with a stack stretching halfway across the observable universe.
This is the vast spectrum over which the different wavelengths of the universe's electromagnetic energy extend. Now the curious thing about this is that the electromagnetic energy radiated by our Sun is restricted to a very, very narrow section of this spectrum. 70% of the Sun's radiation has wavelengths between 0.3 and 1.50 microns and within that narrow band there are three types of light: visible light, near-infrared light, and ultraviolet light.
Three kinds of light might seem quite enough but all three combined make up an almost insignificant section of the total spectrum. Remember our 1025 playing cards extending halfway across the universe? Compared with the total, the width of the band of light radiated by the Sun corresponds to just one of those cards!
Written out in full, 1025 zero's looks like this:
10,000,000,000,000,000,000,000,000
A number that big is pretty meaningless by itself. Let's make a few comparisons. For example, in 4 billion years (the estimated age of the Earth) there are about 1017 seconds. If you wanted to count from 1 to 1025 and did so at the rate of one number a second nonstop, day and night, it would take you 100 million times longer than the age of the earth! If we were to build a pile of 1025 playing cards, we would end up with a stack stretching halfway across the observable universe.
This is the vast spectrum over which the different wavelengths of the universe's electromagnetic energy extend. Now the curious thing about this is that the electromagnetic energy radiated by our Sun is restricted to a very, very narrow section of this spectrum. 70% of the Sun's radiation has wavelengths between 0.3 and 1.50 microns and within that narrow band there are three types of light: visible light, near-infrared light, and ultraviolet light.
Three kinds of light might seem quite enough but all three combined make up an almost insignificant section of the total spectrum. Remember our 1025 playing cards extending halfway across the universe? Compared with the total, the width of the band of light radiated by the Sun corresponds to just one of those cards!
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