>I wonder if there is a name for this phenomenon:
> http://members.tripod.com/jdubikins/test/test.html
>It will look a little like the sun at about 10 degrees above the horizon,
>but it is actually a reflection off the clouds that was quite concentrated
>and lasted for nearly 10 minutes after sunset was complete.
I'm not sure what the "official term" for this is, but it is just plain old
refraction. The cause is nearly identical to the "pools of water" in the
road ahead of you. This will happen when there is a layer of air that is
substantially warmer than another layer. Light will reflect off the warmer
layer. This happens quite often in the springtime over large bodies of
water when the air is much warmer than the water. At sunset you will get
the Omega shaped sun and even a complete reflection of the sun up in the
sky after it has set. In fact, all sorts of neat stuff happens, like ships
sailing upsidedown and also you will get to see lights (street lights,
cars, etc) from 100 miles away. I've spent hundreds of hours on Lake
Michigan beaches watching this happen.
BTW, the same thing happens with sound and radio waves. The rule of thumb
is that they both refract towards the cooler. In submarine warfare the
temperature layers are used for hiding/stealth/stalking purposes.
Submarines have towed sensor arrays that are dragged in the layers above
and/or below so they can "hear" what's going on above/below them. "Piping"
also occurs and it is possible in one spot in the North Atlantic to hear
the sound of a bouy chain banging on a rock off of the African coast. The
sound got there by crossing the Atlantic towards the carribean and then
traveling up the gulf stream to this spot near Iceland. The sound
signiture was that of a Russian sub less than 600 meters away. The
American sub played "cat and mouse" for three days with this phantom sub
and it took a couple months before the Navy finally figured out what was
going on.
Ken Norton
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