Low Power Satellite Based Laser / Imaging System Could Easily Track Activity Disturbing Cheap Reflecting Fibers

Shine a 4 milliwatt 645 nm wavelength dollar store pet laser onto a red reflector lens at night and it explodes into color.
Slender reflective fibers would easily reflect a relatively low power satellite based laser a couple hundred miles back to the satellite and show up on satellite imaging. A very weak magnet on each fiber could orient the fibers in specified directions with respect to the earth's magnitic field it the time it would take to fall hundreds or thousands of feet from a plane.
It would be very difficult to tramp over the fibers without disturbing the orientation.
When Al Quada tries a night time ambush, everyone on the planet knows about it.

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Wind and aerodynamics are much stronger forces than the Earth's magnetic field.
--
Jim Pennino

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And?
Bret Cahill
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And in the real world a "very weak magnet" wouldn't do crap, much less "orient the fibers in specified directions", which, if it would work, would be one direction.
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Have you even calculated the Reynolds number of such a fiber at terminal velocity?
You now look like a complete idiot to anyone who has ever taken continuum mechanics.

Do you think the magnetic element must always be aligned in the same direction as the reflective part of the fiber?
Are you really this dumb or are you just pulling our legs?
Bret Cahill
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Irrelvant to the question at hand.
I know you hate dealing with the real world and don't understand it, but get a kid's cheap compass, remove the cover and blow on it gently.
Watch the needle spin around.
Take the needle and drop it.
Notice that when it lands the orientation is random.

Now you are falling back on insults because your proposition has no defensible foundation.

I never said anything about any particular direction, just that IF your scheme could work, the alignment would be in ONE direction, not "directionS".

Have you nothing to say but insults?
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Reynolds Number is irrelevant to aerodynamics?
Bret Cahill
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No, Reynolds number is a determing factor in how FAST your magic fibers will fall but has nothing to do with the ORIENTATION of their fall.
Since the discussion is about ORIENTATION of your magic fibers and not the falling SPEED, Reynolds Number is irrelevant to the discussion.
If you had the slightest clue what Reynolds number actually is you would know that.
Of course, throwing out a fancy, but irrelevant to the issue, term is a nice red herring when you've backed yourself into a corner.
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Then why did you mention aerodynamics and then say Reynolds number was irrelevant?

Velocity doesn't matter in calculating the Reynolds Number?

Then why did you mention aerodynamics above?

Terminal velocity isn't about speed?

Then why did you mention aerodynamics?
Bret Cahill
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Aerodynamics has more factors than just Reynolds number.

Velocity and Reynolds number are related, but neither has anything to do with orientation.

Because aerodynamics has more factors than just Reynolds number.

Of course terminal velocity is about speed, but has nothing to do with orientation.

Because aerodynamics has more factors than just Reynolds number.

The "discussion" was about the landing orientation of your magic fibers with respect to the Earth's magnetic field, not how fast they would fall.
Do you even know the meaning of the word "orientation"?
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Jim Pennino

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Could you identify these "factors" and how they are relevant to fibers falling at terminal velocity?

How are they "related?"

Then why did you mention aerodynamics?

Can you list these "factors" and explain why you think they are relevant?

Then why did you mention aerodynamics above?

You keep repeating that.
That's typical of someone digging himself into a hole.

You don't think speed would have any impact on the flow regime?
Or you don't think the flow regime has any impact on orientation?

When you are digging yourself into a hole, the smart thing to do is to stop digging.
You are too dumb to stop digging.
Bret Cahill
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Why?
The terminal velocity has nothing to do with the orientation.
Stay on subject if you can.

Well, since Reynolds number gives a measure of the ratio of inertial forces to viscous forces, it is related to drag, which in turn is related to velocity.

Because there is more to aerodynamics than just Reynolds number.

Start with shape and center of gravity which will determine whether a falling object will tumble randomly, be stable along some axis, spin, etc.

Because there is more to aerodynamics than just Reynolds number.

And yet you still don't understand it.

I'd say you are the one in the hole.
There is more to aerodynamics than just Reynolds number.

The "flow regime" is what Reynolds number is about, but since it is a dimensionless number, it has nothing to do with orientation.

There is nothing in "flow regime" that favors any particular orientation with respect to the Earth as in North/South/East/West.

So why don't you educate us all and show us how a dimensionless number influences orientation with respect to the Earth's North pole?
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Jim Pennino

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Because you will get a Nobel Laureate in continuum mechanics if you revealed these mysterious "other factors."
Don't keep the Norwegians settin' on the edges of their chairs . . .

Then why did you bring up aerodynamics?
You think "dynamics" is about zero velocity?

_You_ are the one who claimed aerodynamics was a factor and that Reynolds Number was irrelevant to aerodynamics.

What is related to what kind of drag?
Anyway you dodged the question:
How are velocity and Reynolds Number related?

So velocity _is_ relevant to aerodynamics?

Like what?
We're talking a million Euros . . .

Shape has nothing to do with Reynolds Number?

The designer has no control over center of gravity?


Anything relevant to this discussion?

Certainly not if you cannot post some of these "other factors."

You need to say more about these mysterious "other factors" to have some credibility.

We've been settin' on the edges of our chairs waiting for you to post these "other factors" that make the Reynolds Number "irrelevant."
But you keep dodging and dodging this issue.

Does this mean you don't think speed impacts the Reynolds Number?
Or does this mean you don't think Reynolds Number is relevant to the flow regime?

Then why did you bring up aerodynamics?

Then why wouldn't magnetized fibers orient to some angle with the earth's magnetic field?

=
Anytime you want to sue the folks that ripped you off for your "education" in small claims court just print out this thread and file it with the clerk.
It's 100% guaranteed you'll win.
Bret Cahill
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<snip gibberish and repeated lies>
There are more things that determine the aerodynamic performance of a falling body than Reynolds number.
There are, for example, shape, center of gravity, center of pressure, lift, density, etc.
There are no aerodynamic factors that will lead to any particular orientation of a falling body with respect to terresterial coordinates, i.e. North.
There are several aerodynamic factors which will guarantee a random and unpredictable orientation of a falling body with respect to terresterial coordinates if the result is the falling body is unstable and tumbles.
In summary:
You keep blathering on about Reynolds number as if there is some Reynolds number that will result in a particular orientation.
I have told you over and over again that Reynolds number has absolutely nothing to do with orientation.
Your response is to keep blathering the lie that I said "Reynolds number is irrelevant to aerodynamics".
It has become clear the only thing you know about aerodynamics is there is a thing called Reynolds number and you have no clue what it is or what it means to a falling body.
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Jim Pennino

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if you enlighten the planet about all these other "factors."
Don't keep the poor folk at _Nature_ settin' on the edges of their chairs.
Post these "other factors."
. . .

And how do these "things" preclude fibers from orientating magnetically?

Above you said there were aerodynamic factors that would _prevent_ the fibers from aligning with the earth's magnetic field.
Are you trying to wiggle out of that position?

Can you post anything about these aerodynamic factors?
You will get a Nobel Laureate in continuum mechanics if you enlighten the planet about all these other "factors."

A summary of these "factors?"

Where?
The OP clearly stated that the orientation comes from the earth's magnet field.
You have been claiming that some mysterious aerodynamic "factors" would prevent the fibers from orientating magnetically.
Are you now running from your original position?

Then why did you mention aerodynamics?

You said:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

~~~~~~~~~~~~~~~~~~~~~~~~~~
If you want to run from your original position, by all means, run. The first thing you need to do when you are digging yourself into a hole is to stop digging.
But if you do run, acknowledge that you have abandoned your original position that aerodynamic factors would prevent the fibers from aligning magnetically.
If you don't everyone will know you are disreputable.
Bret Cahill
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I did several times but you keep ignoring them.
You said: "Slender reflective fibers..."
First, the phrase is redundant as the definition of "fiber" is "A slender, elongated, threadlike object or structure."
Ignoring that little problem, unless a falling object is designed such that has a perfectly symetrical, "neutral", and non-turbulent aerodynamic profile, it will either spin, tumble, or have it's orientation changed by random wind gusts.
A elongated, threadlike object or structure is obviously not symetrical off it's long axis, not aerodynamically neutral and subject to having it's orientation changed by any random wind gust off it's long axis.
Of course one could design such a neutral structure, and with precision machining fabricate it, but it wouldn't be a "fiber".
And once again, the Reynolds number of the structure has nothing to do with the falling orientation of the structure.
<snip childish babble>
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Jim Pennino

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