What is Sunlight?
[[File:The Sun.jpg|thumb|An image of the [[Sun]] and of its [[radiation]].]] '''Sunlight''' is the [[light]] and [[energy]] that comes from the [[Sun]]. When this energy reaches the [[earth]]'s [[surface]], it is called [[insolation]]. What we experience as sunlight is really '''solar radiation'''. It is the [[radiation]] and [[heat]] from the Sun in the form of [[electromagnetic wave]]s. The [[atmosphere]] affects the amount of solar radiation received. When solar radiation travels through the atmosphere, some of it is absorbed by the atmosphere (16%). Some of it is scattered to [[Outer space|space]] (6%). Some of it is reflected by [[cloud]]s (28%). About 47% of it reaches the Earth's surface. Without sunlight, there could not be life on the [[Earth]]. [[Plant]]s need sunlight for the process of [[photosynthesis]]. During photosynthesis the plants use the [[energy]] of the sunlight, water, and [[carbon dioxide]], to create [[glucose]] (sugar). The glucose can later be used by the plant for energy or [[animal]]s eat the plant and the glucose in it. Plants need sunlight to grow green. Without enough sunlight but with enough water, the plant grows very tall very quickly, but looks yellow and dehydrated, although when touched, the leaves are very moist. Solar radiation can be both good and bad for a person's [[health]]. When in the light, the [[human body]] uses the [[ultraviolet]] part of sunlight to make its own [[Vitamin D]]. Without [[sunscreen]] too much ultraviolet light can cause [[sunburn]] and [[skin cancer]]. [[Sun angle]] makes difference in [[season]]s on Earth as well as in the length of [[day]] and [[night]].<ref>[http://www.die.net/earth World Sunlight Map from die.net]</ref> A high angle makes the [[tropics]] hot, and a low angle makes the [[arctic]] cold. ==Intensity of sunlight on planets of Solar System== [[File:Antelope canyon jh1.jpg|thumb|220px|Sunlight in the Antelope Canyon, [[Arizona]].]]Different bodies of the [[Solar System]] receive sunlight of different intensities. The table comp