rainbow

rainbow, arc showing the colors of the spectrum, violet inside and red outside, which appears when the sun shines through water droplets. It often appears while the sun is shining after a brief thundershower in the late afternoon or on fog layers. The sun, the observer's eye, and the center of the arc must be aligned—the rainbow appears in the part of the sky opposite the sun. The rainbow is an arc of 180° if the sun is at the horizon, and it cannot appear if the sun is high in the sky. It is caused by the refraction and reflection of rays from the sun on a "sheet" of water droplets. The light is refracted as it enters the sphere of the individual water drop, then is reflected from the drop's opposite side, and is again refracted as it leaves the drop and passes to the observer's eye. When conditions are suitable, a double rainbow may be seen; a larger, paler, secondary rainbow with colors reversed (red inside) outside the primary arc is caused by two refractions and two reflections of the ray while it is inside a drop. The "rainbows" of mist, lawn spray, and spray from a waterfall are similarly caused. The lunary rainbow, seen much less often, is usually observable soon after dark following a brief summer storm or shower when the moon is nearly full. Aristotle was first to devote serious attention to the rainbow, but his mistaken explanation of it misled thinkers for centuries. Descartes in the 17th cent. also attempted to account for the phenomenon but the correct explanation of it could not be furnished until the physics of light and its reflection and refraction were understood and the spectrum explained. In religion and art the rainbow symbolizes God's promise of mercy to mankind after the Deluge (Gen. 9.13). The Greeks and Romans called the rainbow the sign of Iris, messenger of the gods. The Inca and other Native Americans regarded the rainbow as a gift from the sun-god. There are fairy tales of searches for the pot of gold at the foot of the rainbow.

Species (Oncorhynchus mykiss) of fish in the salmon family (Salmonidae) noted for spectacular leaps and hard fighting when hooked. It has been introduced from western North America to many other countries. A brightly coloured fish of lakes and swift streams, it is covered with small black spots and has a reddish band along either side. The steelhead, a large, bluish, oceangoing form, is also a prized game fish. Rainbow trout may weigh 6 lb (2.8 kg); steelheads (and rainbows in large lakes) may weigh 10–20 lb (4.5–9 kg) or more. Another form of rainbow, the Kamloops, or Kootenay, trout of Idaho, may exceed 30 lb (14 kg).

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Series of concentric, coloured arcs that may be seen when light from a distant source—usually the Sun—falls on a collection of water drops such as in rain, spray, or fog. The coloured rays of the rainbow are caused by the refraction and internal reflection of light rays that enter the drop, each colour being bent through a slightly different angle. Hence, the combined colours are separated upon emerging from the drop. The most brilliant and most common rainbow is the so-called primary bow, which results from light that emerges from the drop after one internal reflection. The colours of the arc (from outside to inside) are red, orange, yellow, green, blue, indigo, and violet. Occasionally a less-intense secondary bow may be observed; it has its colour sequence reversed.

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Natural area, southern Utah, U.S. Located on the Navajo Indian Reservation near the Utah-Arizona border, the monument was established in 1910 and occupies 160 acres (65 hectares). It centres on a rainbow-shaped bridge of pink sandstone 290 ft (88 m) above a creek that winds toward the Colorado River. The bridge is 275 ft (84 m) long and is one of the world's largest natural bridges. Embedded among canyons, the area is accessible only on foot, by horseback, or by boat on Lake Powell.

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Rainbow is a census-designated place (CDP) in San Diego County, California, United States. The population was 2,026 at the 2000 census.

Geography

Rainbow is located at (33.411213, -117.149209).

According to the United States Census Bureau, the CDP has a total area of 41.6 km² (16.1 mi²), all land.

Demographics

As of the census of 2000, there were 2,026 people, 739 households, and 523 families residing in the CDP. The population density was 48.7/km² (126.0/mi²). There were 780 housing units at an average density of 18.7/km² (48.5/mi²). The racial makeup of the CDP was 81.44% White, 0.15% African American, 0.79% Native American, 2.42% Asian, 0.79% Pacific Islander, 11.45% from other races, and 2.96% from two or more races. Hispanic or Latino of any race were 21.82% of the population.

There were 739 households out of which 26.9% had children under the age of 18 living with them, 62.2% were married couples living together, 5.3% had a female householder with no husband present, and 29.2% were non-families. 21.7% of all households were made up of individuals and 10.3% had someone living alone who was 65 years of age or older. The average household size was 2.73 and the average family size was 3.15.

In the CDP the population was spread out with 23.7% under the age of 18, 6.0% from 18 to 24, 25.8% from 25 to 44, 26.8% from 45 to 64, and 17.8% who were 65 years of age or older. The median age was 42 years. For every 100 females there were 109.1 males. For every 100 females age 18 and over, there were 110.9 males.

The median income for a household in the CDP was $40,938, and the median income for a family was $44,833. Males had a median income of $38,661 versus $32,917 for females. The per capita income for the CDP was $19,890. About 15.8% of families and 23.2% of the population were below the poverty line, including 33.4% of those under age 18 and 5.5% of those age 65 or over.

History

The area, previously known as "Vallecitos", (little valley), was renamed "Rainbow Valley" in the late 1880s, after Mr. J.P.M. Rainbow, who bought a homestead there.

In October 2007, The Santa Ana Winds fueled a major wildfire in the area.

Politics

In the state legislature Rainbow is located in the 36th Senate District, represented by Republican Dennis Hollingsworth, and in the 66th Assembly District, represented by Republican Kevin Jeffries. Federally, Rainbow is located in California's 49th congressional district, which has a Cook PVI of R +10 and is represented by Republican Darrell Issa.

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