When is the moment the sun sets? WRONG!

mikea

mikea

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Scott Dennstat must sit this one out.

At what moment does the sun drop below the horizon?

http://blogs.discovermagazine.com/badastronomy/2011/11/20/sunsets-are-quite-interesting/

What I want to know is when they do that trick where you can judge how far east or west of another plane you are by timing the sunset. I guess if you both time the same spot it doesn't matter if it's the real sunset.

Does this mean that the official sunset time is earlier than what we see? That could explain the delay I've seen.
 
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mikea said:
Does this mean that the official sunset time is earlier than what we see? That could explain the delay I've seen.
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I believe the official sunset times take the effects of refraction into account. In other words, the almanac gives the time the sun will be seen to set, not the time it actually does set.

I'm basing that on the fact that the length of "daylight" (i.e. sunrise to sunset) as given by sunrise/sunset times is still a few minutes over 12 hours for 2-3 days after the autumnal equinox (and 2-3 days before the vernal equinox).
 
Jedi Mind Trick: This is not the sunset you are looking for.
 
mikea said:
Scott Dennstat must sit this one out.

At what moment does the sun drop below the horizon?
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Actually, 8 minutes before we see it drop below the horizon. It takes light 8 minutes to travel from the sun to Earth.
 
Woah woah in what context? Are we talking about logging night time or logging night landings for currency..? Something about 1 hour after and 1 hour before.. Define civil twilight..

<---<^>--->
 
p1l0t said:
Woah woah in what context? Are we talking about logging night time or logging night landings for currency..? Something about 1 hour after and 1 hour before.. Define civil twilight..

<---<^>--->
Click to expand...

No

geneseib said:
Actually, 8 minutes before we see it drop below the horizon. It takes light 8 minutes to travel from the sun to Earth.
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The time it takes for the photons of light to travel 93million miles to your eye on the surface of the Earth is not relevant. The Sun does not move relative to the Earth, but the observer moves relative to the Sun.

Otherwise, if the Sun were a giant lightbulb in the sky with a Wiz flipping off the switch then it would be relevant.
 
With the Rockies to the West, the sun goes behind them prior to the official sunset time here every day, since it's based on the globe without factoring in big granite lumps. ;)
 
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