The sun will emit the different colors of the visible spectrum roughly with the same intensity. Without this fact, our world will be rather dull in coloration. Sunlight that was more red would mean most things on earth would be red. Plants are green because they absorb reddish pigments to a greater degree, giving rise to green as the color they give off or scatter themselves. Figure 42A shows the light spectrum. You can expect that the color of an item will be the opposite to the color they absorb, and can determine this color by looking opposite to the color of the item: In actuality, the sun emits every wavelength of electromagnetic radiation waves, except for gamma rays. X-rays, UVA, UVB, radio waves, microwaves, and infrared waves are all waves emitted by the sun. It's the infrared rays that help us get warmth from the sun. There are some peak energy frequencies in the color spectrum from the sun, but these are meaningless and do not show up in what we see or perceive from it. The sun also has to has its rays travel through a greater slice of atmosphere during sunrise and sunset, largely because of the curvature of the earth. This means that blue light essentially gets scattered out of being able to pass much through the atmosphere, leaving behind mostly red light. The sunset on the moon would instead be white as there is no atmosphere to scatter the sun's rays.
MOON PHENOMENA AND THEIR MEANING Most people find the moon to be very interesting and will talk often about what phase the moon is in. For example, a full moon indicates that the moon is on the opposite side of the earth from the sun. You know of course that the moon has none of its own radiation so it does not give off light. It only reflects light from the sun. When we see the entire face of the moon with the earth in the moon and the sun, see this as a full moon. When the moon is between the earth and the sun, there is no possible way you can see any light from the sun reflected off from its surface. This is called the new moon. Figure 43 shows the different moon phases:
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