Effects of Polarization and Scattering of Light
The Earth appears as a pale blue dot because of the effects of polarization and scattering of the light reflected from Earth. The polarization effect of planet Earth depends on various factors such as cloud cover, exposed areas of oceans, forests, deserts and snow fields, etc. The contribution of each surface type is a combination of Rayleigh scattering above the surface and reflection at the surface. The integrated effect causing Earth to appear as a pale blue dot depends on wavelength, scattering angle and cloud cover. The degree of polarization is particularly strong in the blue region of the visible spectrum due to Rayleigh scattering in the atmosphere. The degree of polarization for Earth to appear as a pale blue dot at 443 nanometers and 90° scattering angle, as calculated using polarization observations of Earth made from the POLDER satellite radiometer, is 23% for 55% (average) cloud cover and up to 40% for 10% (minimal) cloud cover.
Read more about this topic: Pale Blue Dot
Famous quotes containing the words effects of, effects, scattering and/or light:
“Each of us, even the lowliest and most insignificant among us, was uprooted from his innermost existence by the almost constant volcanic upheavals visited upon our European soil and, as one of countless human beings, I can’t claim any special place for myself except that, as an Austrian, a Jew, writer, humanist and pacifist, I have always been precisely in those places where the effects of the thrusts were most violent.”
—Stefan Zweig (18811942)
“The hippie is the scion of surplus value. The dropout can only claim sanctity in a society which offers something to be dropped out of—career, ambition, conspicuous consumption. The effects of hippie sanctimony can only be felt in the context of others who plunder his lifestyle for what they find good or profitable, a process known as rip-off by the hippie, who will not see how savagely he has pillaged intricate and demanding civilizations for his own parodic lifestyle.”
—Germaine Greer (b. 1939)
“What was he doing, the great god Pan,
Down in the reeds by the river?
Spreading ruin and scattering ban,
Splashing and paddling with hoofs of a goat,
And breaking the golden lilies afloat
With the dragon-fly on the river.”
—Elizabeth Barrett Browning (1806–1861)
“Lady of light, I would admit a dream
To you, if you would take it in your hand.
Will you not let it in a gentle stream
Of living blood? How else may I remand
Your light if not as pulse upon your ear?”
—Allen Tate (1899–1979)