We Must First Understand…
[The other half of] Why sky is blue.
When Sun is high in the sky, it emits wavelengths at the shortest angle
What colour does the shortest angle allow for…?
Blue Sky (Part 2)
Blue light is the shortest distance in atmosphere
Atmospheric gases absorb blue and violet colours and cause them to scatter (more than any other colour)
Human eyes do not register violet well
…and so humans see blue!
Atmosphere – Video
[0:56 – 1:34 min]
Blue never goes away… we just cannot see it sometimes!
Sunrise and Sunset
When Sun reaches Earth, there is a longer angle
What colours does the longest angle allow for…?
As Sun gets higher in sky, these colours fade and blue light becomes more scattered
Blue sky returns
Reverse sunrise… but a bolder display
Dust/debris is being kicked around during the day
This filters light
Polluted cities have the most beautiful sunsets
How are the Details Determined?
Water vapour or humidity causes the sky to appear gray because it deflects light
Adams, Julia. "What Makes the Sky Change Colours?" Colours. N.p., n.d. Web. 8 Dec. 2013.
"Color." The Physics Hypertextbook. N.p., n.d. Web. 9 Dec. 2013. <http://physics.info/color/>.
Corfidi, Stephen F "The Colors of Sunset and Twilight." THE COLORS OF TWILIGHT AND SUNSET. N.p., n.d. Web. 18 Dec.