
	Where results make sense

Topic: Antisolar point

Related Topics

boiling point

neutral point of view

West Point

floating point

point of view

Lagrangian point

fixed point

West Point, New York

Point to Point Protocol

critical point

fixed point mathematics

In the News (Sun 27 Dec 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	Antisolar Region Arcs
		The antisolar point, the point diametrically opposite the sun, is at the bright diamond with the aircraft’s shadow in its centre.
		The diagonal cross is a combination of diffuse arcs from horizontal column crystals and an antisolar arc from Parry oriented columns.
		The Parry antisolar arc extends upwards from the antisolar point to form the two outermost parts of the diagonal cross.
	www.sundog.clara.co.uk /halo/antisol.htm (205 words)

	Arago point. Who is Arago point? What is Arago point? Where is Arago point? Definition of Arago point. Meaning of Arago ...
		The Babinet point is one of the three commonly detectable points of zero polarization of diffuse sky radiation, neutral points, lying along the vertical circle through the sun; the other two are the Arago point and the Brewster point.
		The Arago point, so named for its discoverer, is customarily located at about 20° above the antisolar point; but it lies at higher altitudes in turbid air.
		The Brewster point, discovered by Brewster in 1840, is located about 15° to 20° directly below the sun; hence it is difficult to observe because of the glare of the sun.
	knowledgerush.com /kr/encyclopedia/Arago_point (398 words)

	Antisolar rays
		Antisolar rays are sometimes seen in the direction opposite the sun, converging to the antisolar point (towards the shadow of your head).
		However, perspective causes the rays seemingly to diverge from the sun's position, or, in the case of antisolar rays, converge to the point opposite the sun (antisolar point).
		Antisolar rays are harder to see than the common solar rays, as most of the scattered light causing these rays is scattered in a forward direction, rather than backwards.
	www.weather-photography.com /Photos/gallery.php?cat=optics&subcat=antisolar_rays (346 words)

	Dictionary of Technical Terms for Aerospace Use - A (Site not responding. Last check: 2007-10-19)
		Arc discharge is to be distinguished from corona discharge, point discharge, and spark discharge.
		That point at which a planet, planetoid, or comet crosses to the north side of the ecliptic; that point at which a satellite crosses to the north side of the equatorial plane of its primary.
		Coordinates defining a point on the surface of the earth, or of the geoid, in which the local direction of gravity is used as a reference.
	sulu.lerc.nasa.gov /dictionary/a.html (13387 words)

	handprint : shadows, reflections & atmosphere
		The light vanishing point (lvp, yellow circle for solar point, violet circle for antisolar point) is either chosen arbitrarily for the best visual effect, determined approximately by visual observation in the field, or determined from an ephemeris listing the solar altitude at different times of the day for the location being represented.
		That is, identical points in the object and its reflection lie on a single line perpendicular to the mirror surface, and the reflected object appears at the same distance behind the mirror as the actual object is in front of the mirror.
		However, at the point where the reflections join, the angle of view into the wave front is close to perpendicular to the water surface, so the reflection is weakened and the line of sight may actually penetrate the water (points a and b), darkening the reflection and shifting its color towards blue green.
	www.handprint.com /HP/WCL/perspect6.html (13514 words)

	Diffuse sky radiation (Site not responding. Last check: 2007-10-19)
		The Babinet point is one of the three commonly detectable points of zero polarization of diffuse sky radiation, neutral points, lying along the vertical circle through the sun ; the other two are theArago point and the Brewster point.
		The Arago point, so named for its discoverer, is customarily located at about 20° above the antisolar point; but it lies athigher altitudes in turbid air.
		The Brewster point, discovered by Brewster in 1840, is located about 15° to 20° directly below the sun; hence it is difficultto observe because of the glare of the sun.
	www.therfcc.org /diffuse-sky-radiation-32539.html (407 words)

	Scientific American: Why are rainbows curved? Is it because of refraction in the drops of water? (Site not responding. Last check: 2007-10-19)
		If you are standing outside during the daytime, the antisolar point is marked by the shadow of your head.
		Of course, the region of the sky 42 degrees away from that point is not just one direction but a whole collection of directions, one that forms a circle around the antisolar point.
		These rays produce a secondary rainbow, also centered on the antisolar point, having an angular radius of 51 degrees; the secondary rainbow therefore appears outside of the primary bow.
	www.sciam.com /print_version.cfm?articleID=0009DC14-96A0-1CE2-93F6809EC5880000 (575 words)

	Antisolar iridescence
		Antisolar iridescence can be explained in the same way as that iridescence is explained, reminiscent of large rings of the corona, which are distorted.
		However, for antisolar iridesence it is the glory's rings, which is centered on the antisolar point.
		Antisolar iridescence can sometimes be seen in lenticular clouds opposite the sun, when the sun is low over the horizon.
	www.weather-photography.com /Photos/gallery.php?cat=optics&subcat=antisolar_iridescence (214 words)

	Arago point
		One of the three commonly detectable points, called neutral points, along the vertical circle through the Sun at which the degree of polarization of diffuse sky radiation goes to zero.
		The Arago point (also known as the Arago spot) typically lies about 20° above the antisolar point (where an imaginary ray connecting the Sun and the observer meets the sky), but is found at higher altitudes in turbid air.
		In optics, a bright spot that appears in the center of the shadow of a circular disk illuminated by a point source, caused by diffraction.
	www.daviddarling.info /encyclopedia/A/Arago_point.html (210 words)

	The Rainbow
		Clearly, the antisolar point for the rainbow produced by the reflected light will be as far above the horizon as the original antisolar point was below, which is the altitude of the sun as an angle.
		R is the normal rainbow around the antisolar point A, R' is the rainbow in reflected sunlight around the reflected antisolar point A', and R" is the reflected rainbow.
		The 42° rainbow leaves the axis at point P beyond the sphere, while the 51° rainbow departs from point P' in front of the sphere.
	www.du.edu /~jcalvert/astro/bow.htm (4816 words)

	ACEPT Glossary
		The point at which parallel light rays, incident on a lens (or mirror), are focused after refracting (or reflecting).
		For concave lenses and mirrors, the focal point is on the same side of the lens (or mirror) as the source.
		For convex lenses and mirrors, the focal point is on the opposite side of the lense (or mirror) as the source.
	www.ee.pucrs.br /~pfranco/%D3ptica/1folder/glossa~1.htm (1625 words)

	rainbow (Site not responding. Last check: 2007-10-19)
		The points of the rainbow are 42 degrees from the anti-solar point.
		Using this method of angular measurement the primary rainbow is 3 15 degree fists from the antisolar point.
		The closest point of the rainbow was 4 fists from the sun along the same line.
	www.aolisi.net /rainbow.htm (435 words)

	Los Angeles Pierce College Weather Station (Site not responding. Last check: 2007-10-19)
		However, perspective causes the rays seemingly to diverge from the sun's position, or, in the case of anticrepuscular rays, converge to the point opposite the sun (antisolar point).
		Antisolar Rays: Antisolar rays, also called anticrepuscular rays, are the common solar rays seen opposite the sun, converging to the antisolar point (where the shadow of one's head is).
		Solar and antisolar rays are caused by water vapor and dust in the atmosphere, scattering sunlight.
	www.piercecollege.com /offices/weather/a.html (2624 words)

	Encyclopedia: Anticrepuscular rays (Site not responding. Last check: 2007-10-19)
		They appear to converge at the antisolar point due to perspective.
		This is because for crepuscular rays, seen on the same side of the sky as the sun, the atmospheric light scattering making them visible is taking place at small angles, see forward scattering.
		Perspective is the choice of a single point of view from which to sense, categorize, measure or codify experience, typically for comparing with another.
	www.nationmaster.com /encyclopedia/Anticrepuscular-rays (289 words)

	The Rainbow Bridge by Raymond Lee and Alistair B. Fraser
		The shadow of your head thus covers the antisolar point, the point directly opposite the sun.
		Many drops acting in concert cause the rainbow, and all of these must be at the same angle from the sun (that is, the same angle from the antisolar point).
		Thus at any instant only those drops before you that are on a 42 degrees circle centered about the antisolar point can send you the concentrated rainbow light.
	www.psupress.org /Justataste/samplechapters/justatasteLee.html (2173 words)

	Antonio de Ulloa - Wikipedia, the free encyclopedia
		His name is also recalled as the meterological term Ulloa's halo (also known as Bouguer's halo) which an observer may see infrequently in fog when sun breaks through (for example, on a mountain) and looks down-sun -- effectively a "fog-bow" (as opposed to a "rain-bow").
		An infrequently observed meteorological phenomenon; a faint white, circular arc or complete ring of light that has a radius of 39 degrees and is centered on the antisolar point.
		When observed, it is usually in the form of a separate outer ring around an anticorona.
	en.wikipedia.org /wiki/Antonio_de_Ulloa (322 words)

	Background: (Site not responding. Last check: 2007-10-19)
		Antisolar point: point on celestial sphere 180º from the sun.
		Secondary bow:a rainbow of 52º radius centered on the antisolar point.
		Rainbow angle: 42º the angle between the Sun and the raindrop as seen by the observer.
	www.cord.edu /faculty/ulnessd/legacy/fall2000/hess/legacy/tsld002.htm (46 words)

	The Hindu : Question Corner
		As the point of contact moves away from the centre it reaches a point where many rays return virtually in the same line, and reinforce each other to make a bright return at 41o from the sunline - the line from the Sun to the raindrop.
		These returns happen at all points around the sun- line, and combine to form a bright cone of angle 41o with its axis on the sun-line (see raindrop B in the diagram).
		The antisolar point is the point where an imaginary ray connecting the Sun and the observer meets the ground, coinciding with the top of the observer's shadow.
	www.hinduonnet.com /2001/04/19/stories/08190005.htm (829 words)

	A brief foray into atmospheric optics - PART I
		This is known as your “antisolar” point and is the domain of all primary bows.
		In this instance, the central point of light is displaced due to the redirection of the solar beam.
		Rays of light carrying the image of the sun are bent at the points of entry to these layers due to changes in composition, pressure and meteorological conditions.
	www.gcrg.org /bqr/6-4/optics.htm (2245 words)

	[No title] (Site not responding. Last check: 2007-10-19)
		Notice that there is an initial refraction at the point of entrance, a subsequent total internal reflection, and a final refraction at the point of exit.
		This is true for all drops located at the edge of a cone whose axis points to the sun, and whose apex is the observer's eyes, i.e.
		The antisolar point is the exact opposite of the solar point (where the sun is located), with respect to the observer's head (or more precisely, his/her eyes).
	astrosun.tn.cornell.edu /~akgun/Write/optique.html (730 words)

	AMS Glossary
		Having a radius of only a few degrees, the glory often surrounds an airplane's shadow cast on a cloud or a mountain climber's shadow cast on fog in a valley.
		Thus corona discharge is an example of glow discharge, but point discharge is not.
		Relatively high electric field strengths are required for glow discharges, for the density of radiatively recombining gas atoms and molecules must be high.
	amsglossary.allenpress.com /glossary/browse?s=g&p=22 (524 words)

	nytemp (Site not responding. Last check: 2007-10-19)
		The largest exit angle, about 42 degrees measured with respect to the axis, is for Ray 7, called the Descartes ray after the scientist who first traced ray paths inside raindrops.
		The antisolar point (the point opposite the sun) is at the shadow of your head.
		Drops inside the primary rainbow (at angular distances less than 42 degrees from the antisolar point) also send light back to the observer, but it is not colored because there is no concentration of refracted light inside the rainbow as there is near the Descartes ray.
	www.weatherwise.org /qr/qry.rainbows.html (504 words)

	Antisolar
		All objects at the antisolar point are in front of their shadows.
		It is the brightest point around, because as you move away from the antisolar point more of the shadows become visible.
		I knew that during an eclipse the moon would be at the antisolar point, and that my shadow, growing longer in the sunset, was aimed exactly in that direction, so I merely pointed past the end of my shadow and tried to appear wiser than I really am.
	www.starspangledbanter.com /AntiSolar.htm (1220 words)

	ch3
		Because of Skylab's orientation, with the solar panels pointing at the Sun 99 percent of the time, the pans facing in the direction of Earth's motion around the Sun collected more particles per unit time than did the covers.
		The photometer was attached to the end of a boom that extended from the airlock in the wall of the orbital workshop.
		The two instruments were positioned at the end of the boom on a two-axis mounting that permitted a fixed-position or a scanning observation of selected areas of.....
	history.nasa.gov /SP-404/ch3.htm (4110 words)

	Rainbow Finder
		Abstract: In this activity, rainbow seekers make an inexpensive device which illustrates that the primary rainbow is seen about 42 degrees up from the antisolar point, or up about four fists stacked above the top of the shadow of the viewer’s head.
		The red color appears in a circle—a portion of which is seen as the rainbow arc—roughly 42 degrees from the antisolar point, as suggested by Rene Descartes in 1637.
		The spot where the shadow of her head is cast is the antisolar point.
	analyzer.depaul.edu /paperplate/Rainbow%20Finder.htm (537 words)

	Primary and Secondary Rainbows
		Rainbows result from refraction of sunlight in falling water droplets plus reflection of the light from the back of the droplet.
		The secondary rainbow is about 10° further out from the antisolar point than the pimary bow, is about twice as wide, and has its colors reversed.
		According to Schaaf, the light of the secondary bow is one-tenth the intensity of that of the primary bow, given the same viewing conditions.
	hyperphysics.phy-astr.gsu.edu /hbase/atmos/rbowpri.html (362 words)

	Glories - discussion
		It is similar to the corona often seen around the moon - a series of concentric coloured rings - but instead of being centred around the moon, the glory appears around the shadow of the aircraft projected on to the layer of cloud below.
		They are centred around a point which lies on an extension of the line joining the sun and the aeroplane.
		The antisolar point is that of the observer so the luminous coloured halos are centred on the position of the observer’s head shadow.
	freespace.virgin.net /ljmayes.mal/var/glorytxt.htm (1476 words)

	Crepuscular Rays: sun rays converging on the horizon
		Crepuscular rays are often red or yellow in appearance because blue light from the sun is selectively scattered out of the beam by air molecules.
		Light rays scattered by dust and haze occasionally appear to converge toward the "antisolar" point, (the location on the horizon opposite the point where the sun is setting).
		These rays, called anti-crepuscular rays, originate at the sun, cross over the sky to the opposite horizon, and appear to converge toward the antisolar point because of perspective.
	ww2010.atmos.uiuc.edu /(Gh)/guides/mtr/opt/air/crp.rxml (229 words)

	Light phenomena
		The enhanced brightness near the the solar point, and covering an area 6° by 10°, is the Gegenschein or counter-glow.
		The result is a spot of increased light intensity and colour separation, red towards the sun, in the 22° halo each side of the sun, where the halo would intersect the parhelic circle, and sometimes with a white tail pointing away from the sun.
		The anthelic point may be the centrepoint for various reflection / refraction phenomena - the anthelic arcs.
	www.auf.asn.au /meteorology/section12.html (4049 words)

Try your search on: Qwika (all wikis)