06 January 2008

Misconceptions

all of these from Wikipedia:

When a meteor lands on Earth, it is not usually hot. Small meteorites are not hot when they fall to Earth — in fact, many are found with frost on them. A meteorite has been in the near–absolute zero temperature of space, so the interior of it is very cold. A meteor's great speed is enough to melt its outside layer, but any molten material will be quickly blown off (ablated), and the interior of the meteor does not have time to heat up because rocks are poor conductors of heat. Also, atmospheric drag can slow small meteors to terminal velocity by the time they hit the ground, giving them time to cool down.

Lemmings do not engage in suicidal dives off cliffs when migrating. This misconception is due largely to the Disney film White Wilderness, which shot many of the "migration" scenes on a large turntable in a studio. Photographers later pushed the lemmings off a cliff using a broom.

The blue color of lakes and oceans is not only a reflection of the blue sky. Water looks blue because water is blue; the water molecules do absorb some light, and they absorb red frequencies more than blue. The effect is small, so the blue color only becomes obvious when observing layers of water many meters (or more) thick. (This effect is noticeable to a lesser amount in white-painted swimming pools.) In salt water or mineral-laden fresh water, the color of dissolved minerals can also be seen. Sky-reflection does play a role, but only when the water surface is very calm, and only when the water is observed at a glancing angle less than approximately ten degrees.

The word "theory" in "the theory of evolution" does not imply doubt in mainstream science about the validity of this theory; the words "theory" and "hypothesis" are not the same in a scientific context (see Evolution as theory and fact). A scientific theory is a set of principles which, via logical deduction, explain the observations in nature. The same logical deductions can be made to predict observations before they are made. The theory describing how evolution occurs is a "theory" in the same sense as the theory of gravity or the theory of relativity.

The Wright Brothers did not make the first heavier than air flight. New Zealander Richard Pearse takes the prize, nine months before O & W.

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