Sun tanning However, it operates not by inducing direct DNA damage, but by producing reactive oxygen species which damage DNA indirectly. UVA (see above) induces a cosmetic tan but little extra melanin protection against sun damage, sun burn, or cancer. Ultraviolet B (UVB) radiation is in the wavelength range 280 to 320 nm. Much of this band is blocked by the Earth's ozone layer, but some penetrates. UVB: A person's natural skin color affects their reaction to exposure to the sun. An individual's natural skin color can vary from a dark brown to a nearly colorless pigmentation, which may appear white .
The empire on which the sun never sets the sun encircles.” Mesopotamian texts contemporary to Sargon of Akkad (c. 2334 – 2279 BC) proclaim that this king ruled “all the lands from sunrise to sunset.” In the early 16th century, the phrase, ""el imperio en el que nunca se pone el sol"" ("the empire on which the sun never sets") originated with a remark made by Fray Francisco de Ugalde to Charles I, who as king of Spain and as Holy Roman Emperor by the name of Charles V, had an empire, which included many territories in Europe, islands in the Mediterranean and Atlantic, cities in North Africa