Talk:Sunlight

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Spectrum?[edit]

It would be nice to have picture showing the spectrum as seen thru a prism, accompanied by an intensity graph, for both the actual spectrum of the Sun and the spectrum as seen at sea level on Earth. --TiagoTiago (talk) 07:27, 4 June 2013 (UTC)

Gamma rays[edit]

While the gamma rays created through fusion in the core do not make it out to the photosphere, the Sun does occasionally emit gamma rays during solar flares (as observed by RHESSI and Fermi), and it does emit a small background of gamma rays resulting from cosmic rays impacting the photosphere (as observed by Fermi). Spacehippy (talk) 17:39, 5 December 2013 (UTC)

Atmospheric filter[edit]

I agree with the value of spectranalysis. Is it coincidence that the sky away from the sun looks light blue and the difference between the visible [solar spectrum] above & below the atmosphere is somewhat greater in blue? My intuition (for what it is worth) says that light blue implies broad spectrum (white) with an excess of blue produces a light blue. On a possibly related issue, is some 'average' of the yellow sun and the blue sky (maybe plant green too), a basis for our evolved perception of white?
--Wikidity (talk) 23:36, 23 March 2014 (UTC)

Sunbathing bla bla[edit]

Totally off-topic imho:

"Women often try to shift or remove clothing straps from areas that would be exposed by a different style of clothing. This means the area gets some tan and strap marks are not too obvious. One way this is done is to remove straps while lying face down, so as to avoid being seen topless. Another way is to adjust the straps slightly a few times while tanning."

I would simply delete the section. The text before and after this paragraph isn't much better. — Preceding unsigned comment added by 80.187.108.19 (talk) 15:18, 6 May 2014 (UTC)

Summary[edit]

I don't see why "A photon starting at the centre of the sun and changing direction every time it encounters a charged particle would take between 10 000 and 170 000 years to get to the surface." should be stated so early. That is not actually a significant part of the process by with sunlight is generated.

It's not even a meaningful part. Photons are just packets of electromagnetic energy obeying Bose-Einstein statistics and as such don't have identities. Particles absorb and emit photons but an emitted photon can't be identified with any specific absorbed photon; if it could it would obey Fermi-Dirac statistics. Putting this sentence right after the 8.3 minutes for sunlight to reach Earth implies an impossibly slow flow of energy from the center of the Sun to the surface. Vaughan Pratt (talk) 06:32, 27 July 2014 (UTC)

Luminance and retinal damage[edit]

I suggest that "burning glass" retinal damage be included in Effects on human health. It is largely the result of the high luminance of sunlight. This is easily observed in the increase of vision problems after solar eclipses, but it is much more common than that. Luminance is related to the light intensity at the sun's surface, unlike illuminance which is the intensity at the Earth's surface.

An other health effect may be macular degeneration due to cumulative exposure to blue light, but that may be too subtle to include here, at this time.