Sunlight and Moonlight Reflection

This is a simple optics question, but I can't figure it out.I work on Lake Ossipee in NH and watch the sunset almost everyday. I'm curious as to why the sun(and moon) reflect a line of light off the water extending right to the observer.That is, you don't see the sun reflected in the water like you would see the mountains reflected. You see a line of light starting at the opposite end of the lake and extending to the nearer part of the lake.The problem is this: the sun is so far away that the incident light rays can be thought of as being parallel to each other. ( Didn't Eratosthenes use this assumption when estimating the circumferance of the earth?) This being the case, why don't we just see the circular reflection of the sun in the water? Why is it distorted into a line? The same problem can be said for the moon.I think it might be because the atmosphere distorts and scatters the sunlight, but I'm not entirely sure.Another question. Sometimes during the night the moonlights reflection will start off at the far side of the lake and extend towards the observer, but it will have periodic breaks, i.e., dark spots on the band of light on the water.And last question: why is the band wider the farther way it is?These are pretty elementary questions but I can't find any references online, so I figured I'd ask the semi-geniuses here at EvC.Thanks,
JustinEdited by humoshi, : No reason given.

Thread copied here from the Sunlight and Moonlight Reflection thread in the Proposed New Topics forum.

Pictures would be cool, the periodic breaks seems like interference to me though.

The breaks are, I think, caused by waves. If the surface was smooth they wouldn't be there.The rest is not so obvious to me. I think it is a helluva good question.A guess is that it is just because the rays are parallel. The bottom of the moon ray is reflected off the water a considerable distance away and the top is ray is closer. In my mind I think this explains it but I can't do it without some ray tracing which I am not sure is worth the time when one of the knowledgeable folks will answer it quickly in a day.

The reason that you see the moon or sun stretched out is because the photons hit the water and 'skim' the surface like when you skim pebbles off the water.Some photons can 'bounce' seven or eight time before they are absorbed by your eyes.The reason it seems a wobbly reflection is the zig zag path the photons take after they intercept the water. Water being wobbly imparts it's relative motion to the photons.

Bullshit - they cannot possibly bounce more than five times - unless you have evidence to the contrary???

Poor, sweet Cavediver.Skimming Photons! - a photo on Flickriver

Err, quite clearly photoshop...

I believe the technical term for this phenomenon is 'Glitter Path'.As cavediver suggests Larni's 'skimming' photons are a fanciful, if poetic, explanation. In fact it is the uneven surface of the water, caused by waves, that leads to this effect. What you are seeing is actually lots of smaller reflections where the light source, be it sun moon or whatever, hits the waves and then the viewer's field of vision. On a perfectly flat surface only 1 reflection would be produced, because of the imperfections in the surface you get instead multiple reflections.As to the question of the suns rays being parallel, I don't think they are. Just beacause Eratosthenes could assume they were for the purposes of his calculations doesn't mean that they actually are parallel.I'd suggest that the periodic breaks are probably due to differences in the waves caused by effects of wind or changes in the character of the bottom beneath the waves, i.e. sudden changes in depth.TTFN,WK*ABE* In fact if you look at Larni's linked picture you can see changes in the water where the breaks are, it is slightly darker suggesting a gust of wind in that area, you are only seeing reflections from waves which produce the correct angle of incidence.Edited by Wounded King, : No reason given.

Nothing fanciful at all - it's just that Larni was exaggerating the number of bounces possible...

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I work on Lake Ossipee in NH and watch the sunset almost everyday. I'm curious as to why the sun(and moon) reflect a line of light off the water extending right to the observer.

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That is, you don't see the sun reflected in the water like you would see the mountains reflected. You see a line of light starting at the opposite end of the lake and extending to the nearer part of the lake.

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I think this is simply due to ripples on the surface of the water. The low, glancing angle of incidence makes the reflection (and the apparent light source position) very sensitive to the plane of the water. The vertical position is much more sensitive to angle than the horizontal. So if there are any ripples, the vertical image will get stretched much more than the horizontal, making the line that you see. I believe it is simply a geometric effect.This should also be true of scenery that is very low on the horizon; it should be blurred in the vertical but more distinct in the horizontal. And this should be less pronounced when the waters are more calm. If you can find a day when the lake is frozen with no snow, it would be interesting to compare the appearance with what you noted.

Thanks for the help!