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I'm not sure but I think, not necessarily. They add dimples to golf balls to increase their flight distance and straighten their flight trajectories specifically to disrupt laminar flow, because over a sphere, turbulent flow actually can work better, if the dimples are just the right size and have just the right irregularity. I don't know for sure if it can be applied to aircraft though; maybe it only works on golf balls. Reference here.

http://www.kisa.ca/asl.html

http://www.masterstech-home.com/ASLDict.html

http://commtechlab.msu.edu/sites/aslweb/browser.ht m

http://wings.avkids.com/Book/Signing/

Other estoteric ASL signs are:
http://deafmissions.com/dic/ADRSindex.html (religious)

Lets make some assumptions about your answer.

Based on the size of the abberation, the bug would have to be fairly small. We'll say no bigger than a housefly.
Houseflys move at about 4.4mph.
If it was moving at top speed, that's 10 cm (3.9 inches) that it flew in 1/20 sec.
My question is, using trig and the size of lightposts in Australia, how far away from the camera is your bug and does the size of the flash jive with the size of the bug at that distance?

Also, why is the white pattern around the lightpost symmetrical about the axis of the dark streak? Wouldn't a bug flying sideways in the picture be asymmetrical in relation to its flight path?

I think it's something to do with the reflection of the sun off of an off-frame airborne object.

For ideas, check out the second chapter of Drexler's Nanosystems, google for Reynolds Number, and look around...

--MarkusQ

Hmm, you've got me thinking now. I think I tried it many years ago, and that it gave the expected result. There are a couple of sites that detail this: here and here (with QT movie). But your point about the oxygen not just magically disappearing is a good one. Other sites claim that the experiment is actually a hoax, and that the rise in water level is not due to the oxygen being used up, but because the air inside the jar is heated by the candle, and then contracts when the candle goes out, drawing the water in. So I guess my example was a poor one - the candle *is* effectively filling the jar with phlogiston (or CO2) as you and the gp suggested. This site has a discussion of the experiment, and shows an experiment with steel wool that does a better job of showing the proportion of oxygen in air.

Why does a golf ball have dimples?

Part of the problem is the definition of "hotter" and "cooler". Temperature is a measure of the average kenetic energy of molecules. At the surface of the earth, where all things have roughly equal densities, we learn to expect certain things about heat transference. In a near vacumn, the molecules can be very "hot", but the heat doesn't transfer to denser objects. Thus, the following facts:

• Temperature in the troposphere decreases with height to -76 degrees Fahrenheit.
• In the lower levels of the stratosphere the temperature remains the same, but in the upper levels the temperature actually increases to roughly the same as that at sea level.
• In the mesosphere, which extends to about 50 miles, temperature drops again to as low as -173 degrees F.
• The thermosphere extends to 400 miles and is characterized by large fluctuations of temperature (thermo means "heat"). At these heights there are relatively few molecules and heat retention should be low. However, within the thermosphere solar energy is absorbed and reradiates heat. At its upper limits the temperature reaches 441 degrees F.

It's interesting to note that drag racing is intentionally "old-school". They have made it so that the competitors are racing virtually identical equipment, so it's all down to the pit crew (heck, the driver just presses a button and steers, the car does the shifting). The run the engines so hot, that the pit crew has to rebuild the enginge after every race, sometimes within only a few hours.

Most of my info came from some show, and this is all I could find about these restrictions on the web.

And NO these planes does not plummet to earth vaporised by their own instability if the on board computers fails, which seems to be the common belief. The normal solution as seen in the Swedish JAS or the Eurofighter is to have forward stabilisers that if in "serious shit" can be set to flow freely automatically or by the pilot. This gives the plane enough stable aircraft behaviour so that a good pilot can fly it without computer assistance. But you need of course to have some juice in the fly-by-wire system otherwise you have to steer by thrust (which is perfectly doable if you have two engines but difficult).

Do some homework dude. And who the ... are modding these days!? ;-)

Cheers Patrix