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Thread: Meteors

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    kencrowder's Avatar
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    Default Meteors



    Since there was a lot of interest in how gravity works and we only mentioned terminal velocity, I thought it might be interesting to look at drag which causes terminal velocity. The best example I could think of was meteors. We all enjoy seeing them.

    The drag on a ball is roughly equal to the presented area (cross section) and the velocity squared. So, if I double the radius of a ball it has 4 times the area. But it has 8 times the volume. Thus it has 8 times the mass if both balls have the same density.

    The drag is also dependant on the density of the air. Surface air is much more dense than say the troposhere.

    The drag on a meteor is converted to heat. When that is sufficient, it glows, melts and then disintegrates.

    The earth is traveling at about 100,000 ft/sec around the sun if I did the math right. So most meteor velocities will be around that value.

    So consider two meteors. One is twice as large as the other but then has 8 times the mass. But it only has 4 times the drag. The heat is being generated 4 times as fast, but it needs 8 times as much heat to disappear.

    If it only skims the stratosphere it will see less drag than if it hits below the stratosphere. How bright it is depends on distance and size.

    The next time you see one, consider what is really going on. We miss a lot if we simply make a wish.

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    Default

    Lol...I like the insight. Makes us think. I have seen more "shooting stars". In the past few months then I did my entire life. I just got into observation...likely reason why😁

    However, when my wife and I were younger we were chasing UFOs for miles...then we realized it was a meteor shower! Good times!
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