Facts about Rainbow
Secondary rainbows are caused by a double reflection of sunlight inside the raindrops, and appear at an angle of 50°–53°.
The most spectacular rainbow displays happen when half of the sky is still dark with draining clouds and the observer is at a spot with clear sky in the direction of the Sun.
Supernumerary rainbows are clearest when raindrops are small and of similar size.
The closely spaced outer bow has been observed to form dynamically at the same time that the outermost (tertiary) rainbow disappears.
Young's work was refined in the 1820s by George Biddell Airy, who explained the dependence of the strength of the colors of the rainbow on the size of the water droplets.
The radius of a Titan rainbow would be about 49° instead of 42°, because the fluid in that cold environment is methane instead of water.
The circumhorizontal arc is sometimes referred to by the misnomer 'fire rainbow'.
Higher-order rainbows were described by Felix Billet (1808-1882) who depicted angular positions up to the 19th-order rainbow.
Rainbows can be caused by forms of water other than rain, including mist, spray, and dew.
The very existence of supernumerary rainbows was historically a first indication of the wave nature of light, and the first explanation was provided by Thomas Young in 1804.
A supernumerary rainbow is an infrequent phenomenon, consisting of several faint rainbows on the inner side of the primary rainbow, and very rarely also outside the secondary rainbow.
A reflected rainbow will appear as a mirror image below the horizon (see photo above).
Knowing that the size of raindrops did not appear to affect the observed rainbow, he experimented with passing rays of light through a large glass sphere filled with water.
The rainbow has a place in legend owing to its beauty and the historical difficulty in explaining the phenomenon.
One type of tertiary rainbow carries with it the appearance of a secondary rainbow immediately outside the primary bow.
The reflected rainbow is frequently visible, at least partially, even in small puddles.
In Chinese mythology, the rainbow was a slit in the sky sealed by Goddess Nьwa using stones of five different colors.
The position of a rainbow in the sky is always in the opposite direction of the Sun with respect to the observer, and the interior is always slightly brighter than the exterior.
The Persian astronomer, Qutb al-Din al-Shirazi (1236–1311), gave a fairly accurate explanation for the rainbow phenomenon.
Rarely, a moonbow, lunar rainbow or night-time rainbow, can be seen on strongly moonlit nights.
The Iraqi physicist and polymath, Ibn al-Haytham (Alhazen; 965-1039), attempted to provide a scientific explanation for the rainbow phenomenon.
A sixth-order rainbow was first observed by K. Sassan in 1979 using a HeNe laser beam and a pendant water drop.
Occasionally, a secondary rainbow is seen, which appears as a fainter arc outside the primary arc, with colors in the opposite order, that is, with violet on the outside and red on the inside.
Paul Dong writes that Shen's explanation of the rainbow as a phenomenon of atmospheric refraction "is basically in accord with modern scientific principles.
Rainbows can be observed whenever there are water drops in the air and sunlight shining from behind a person at a low altitude angle (on the ground).
Historically, a rainbow flag was used in the German Peasants' War in the sixteenth century as a sign of a new era, of hope and of social change.
The result is a luminous rainbow that contrasts with the darkened background.
Occasionally, a second, dimmer, and thicker secondary rainbow is seen outside the primary bow.
A rainbow does not actually exist at a particular location in the sky.
Special rainbows may appear when a rainbow is seen above a body of water, if the water surface is quiet.
Modern physical descriptions of the rainbow are based on Mie scattering, work published by Gustav Mie in 1908.
Seawater has a higher refractive index than rain water, so the radius of a 'rainbow' in sea spray is smaller than a true rainbow.
Given the different angles of refraction for rays of different colors, the patterns of interference are slightly different for rays of different colors, so each bright band is differentiated in color, creating a miniature rainbow.
Theodoric of Freiberg is known to have given an accurate theoretical explanation of both the primary and secondary rainbows in 1307.
During this change, the two remaining rainbows have been observed to merge into a band of white light with a blue inner and red outer band.
The rainbow effect is also commonly seen near waterfalls or fountains.
Advances in computational methods and optical theory continue to lead to a fuller understanding of rainbows.
The alternating faint rainbows are caused by interference between rays of light following slightly different paths with slightly varying lengths within the raindrops.
A third, or tertiary, rainbow can be seen on rare occasions, and a few observers have reported seeing quadruple rainbows in which a dim outermost arc had a rippling and pulsating appearance.
A visitor might need infrared goggles to see the rainbow, as Titan's atmosphere is more transparent for those wavelengths.
The rainbow appears on the Gay pride flag, designed by Gilbert Baker for the 1978 San Francisco's Gay Freedom Celebration and today it is often used to represent LGBT-friendly businesses or districts.
Walking towards the end of a rainbow will cause it to move further away.
A rainbow is an optical and meteorological phenomenon that causes a spectrum of light to appear in the sky when the Sun shines onto droplets of moisture in the Earth's atmosphere.
From an aeroplane, one has the opportunity to see the whole circle of the rainbow, with the plane's shadow in the centre.
Knowing that the size of raindrops did not appear to affect the observed rainbow, he experimented with passing rays of light through a large glass sphere filled with water.
Supernumerary rainbows are slightly detached and have pastel color bands that do not fit the usual pattern.
When sunlight and raindrops combine to make a rainbow, they can make a whole circle of light in the sky. But it's a very rare sight. Sky conditions have to be just right for this, and even if they are, the bottom part of a full-circle rainbow is usually blocked by your horizon.Jun 23, 2017
Rainbows happen when sunlight and rain combine in a very specific way. The beams of sunlight separate into the colors we see in the rainbow as they enter a raindrop. Sunlight is actually made up of different colors that we don't usually see. When a beam of sunlight comes down to Earth, the light is white.
A rainbow table is a precomputed table for reversing cryptographic hash functions, usually for cracking password hashes. Tables are usually used in recovering a plaintext password (or credit card numbers, etc.) up to a certain length consisting of a limited set of characters.
-We see rainbows when the sun is behind us and falling rain is in front of us. -When sunlight strikes a falling drop of water it is refracted, changed in direction, by the surface of the water. The light continues into the drop and is reflected from the back of the drop to the front.