* Sonic booms. These are caused by hydrodynamic shocks induced by traveling faster than the air's speed of sound; an abundance of theory, computation, and observations point to their always happening. I myself had once worked on hydrodynamic computations for material falling onto a moving massive object, and when that object moved supersonically, a sonic boom would always form.

So why don't supersonic UFO's produce sonic booms?

* Mechanical reliability. Why don't they ever crash? Or break down? This is an especially serious problem if they are as abundant as some UFOlogists seem to think that they are.

* "Flying Saucer" shape. This is an atypical shape for flying vehicles; the large majority of airplanes have a missilelike fuselage, because that helps reduce air-friction drag.

* Why traveling with lights on? An important purpose of night lights on vehicles is to advertise their presence; so why would some extraterrestrials on a surveillance mission let their spaceships' presence get advertised if they could possibly avoid doing so?

* The advanced-technology problem. One counterargument is that the UFOnauts have such advanced technology that their spaceships can avoid making sonic booms, that they can easily overcome air drag, and that are either super-reliable or able to avoid leaving pieces of themselves behind. However, this sort of hypothesis can explain anything, and therefore really nothing; as Karl Popper would say, it is difficult to imagine what would falsify it.

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Maybe those lights are actually engines and the saucer shape is what allows it to break the sound barrier without a boom.

Or maybe they just don't exist.

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Maybe those lights are actually engines and the saucer shape is what allows it to break the sound barrier without a boom.

Or maybe they just don't exist.

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I've always wondered why the U.S. Air Force (or ANY air force) didn't adapt the saucer shape if it was so good aero-dynamically speaking. Or, maybe it really IS a piece of junk, that no self-respecting alien pilot would be caught dead flying.

(:raig

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"Flying Saucer" shape. This is an atypical shape for flying vehicles; the large majority of airplanes have a missilelike fuselage, because that helps reduce air-friction drag.

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And yes, in the 1890's, there was a rash of "mysterious airship" sightings.

Edited by - lpetrich on 08/11/2001 08:46:41

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It would be interesting to go back through 19th century literature to see what people called UFOs then. I choose the 19th century as it is well into the "age of enlightenment", but before the advent of those infernal flying machines. Maybe 19th century folk thought UFOs were those Frenchy hot air balloons?

(:raig

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~Sonic booms~ Similar to 600mph torpedoes that ‘blow' a bubble of air in front of them, to achieve such incredible underwater speeds. They, if they exist, may also ‘blow' a vacuum in the direction they wish to travel.

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Very interesting line of discussion!

My two cents would be that UFOs were invented by bored children (or bored child-like adults) with frisbees and cameras and wild imaginations. Later on, UFOs were just the result of wild imaginations about celestial objects which were, indeed, *unidentified*. With the amount of light pollution, identification of anything would be difficult, and misconceptions, combined with mental aberrations, could result from pre-senile minds.

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