Laser beams being aimed at airliners?

"Larry Dighera" wrote in message
...
On Wed, 5 Jan 2005 12:05:22 -0600, "Gig Giacona"
wrote in
::


So the request is still out there. Do you have any cite for your theory
that
there are microphones scattered over metro areas to triangulate
gunshots?


http://student-voices.org/news/index.php3?NewsID=10195
April 7, 2004
Police cams to add gunshot detectors

by Fran Spielman, City Hall Reporter
Chicago Sun-Times

Chicago - Big Brother isn't just watching the bad guys in Chicago. By
late summer, he'll be listening as well -- for the sound of gunshots.

Gunshot detection technology -- capable of "triangulating within 20
feet" the location of a shooting -- is being added to 30 surveillance
cameras already in place on high-crime corners and to 50 new cameras
expected to be installed by late summer at undisclosed locations.

WOW!!! 30 camera in the city of Chicago is "microphones scattered over metro
areas".

Larry is a salesman's delight!!
--
Matt
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO

There may not be that many photons involved, but they are all coming from
the same direction, and that does count for something.

I assume you mean directed at the same point. In this case, light is acting
like a bunch of particles. It would be the same from a flashlight though.

Yes, I meant directed at the same point. With a flashlight the
photons are sprayed all over the place.

Jose
--
Money: What you need when you run out of brains.
for Email, make the obvious change in the address.

On Wed, 5 Jan 2005 16:19:06 -0600, "Gig Giacona"
wrote in
::

And these are your cites for to back up the statement that there are systems
in place in all metro areas to triangulate gunshots?

Here's what I said:

"These days, in the metropolitan areas there are microphones on
every traffic-controlled intersection that can be used to
triangulate the report of the weapon to determine its location."

I didn't say "all metro areas." You inferred that.

My use of the absolute 'every' should have given you a clue, that
there was some hyperbole here.

In English the modifying adjective precedes the noun it modifies
(unlike some other languages). I made no reference to 'all' nor
'every' metro area. The absolute (every) that I used referred to
'intersections'.

But it's obvious you're not concerned that these systems are now in
place around the nation. Your's just looking to make me wrong, or
else you would have addressed the issue of "Big Brother" eavesdropping
on the urban proletariat instead of pressing your point.

THey are, on the other
hand, pretty damn good cites to prove you were wrong since they all are
talking about a pilot program taking place in a few high crime locations in
a couple of cities.

A 'couple' is usually two. I count more than a couple: Chicago, Los
Angeles, Dallas, San Diego, Redwood City ...

If you had bothered to look here
http://www.shotspotter.com/customers.shtml , you'd have known that one
ShotSpotter has systems currently operating in:

Redwood City, CA
Willowbrook, CA
City of Industry, CA
Glendale, AZ
Charleston, NC

There's more information he
http://www.safetydynamics.net/recent_press.htm
http://www.informationweek.com/showA...icleID=6500206

Although this technology may aid law enforcement, I find it a bit too
Orwellian for my taste.

Welcome to the 21st century. :-(

On Wed, 5 Jan 2005 23:30:57 -0500, "Happy Dog"
wrote in : :

"Larry Dighera" wrote in message
.. .
On Thu, 06 Jan 2005 03:52:02 GMT, Jose
wrote in ::

There may not be that many photons involved, but
they are all coming from the same direction, and that does count for
something.

If I'm not mistaken, coherent laser light is all in phase. Doesn't
that cause it to have more energy?

No. The energy is measured in watts like any other kind of power source.

I was referring to the phenomenon of light coherence. There's an
explanation of it he
http://whatis.techtarget.com/definit...4527%2C00.html

And my point was that because the light of a laser is coherent (in
phase), it will provide more energy than an equally bright light
source whose radiation is out of phase. At least this is what I was
told by an EE.

In article , Jose wrote:

I don't know whether it counts for the alleged problems, but there is
a nontrivial difference betweem laser light and the diode in your
headband.

Yes, the nontrivial differences are that my headband is around a thousand
times closer and puts out a hundred times as much energy.
We're not talking about a precision instrument here. How big a circle would
be illuminated at 5000 feet? If it spreads even 0.01 degree it's over a foot
in diameter. 5 mW spread over a couple square feet? I'm extremely
skeptical of this. Extremely.

Mike Beede

Yes, the nontrivial differences are that my headband is around a thousand
times closer and puts out a hundred times as much energy.
We're not talking about a precision instrument here. How big a circle would
be illuminated at 5000 feet? If it spreads even 0.01 degree it's over a foot
in diameter. 5 mW spread over a couple square feet?

The energy of your diode in the cabin is spread out quickly. (and I
don't know whether the laser in question is 5 mW)

Take an ordinary pocket laser ("cat toy") and aim it at the ground on
a sunny day and you will =still= see the spot. Place it far enough
away so the spot is faint, and focus it with a magnifying glass and it
will be as bright as ever. To do this, the brighness of the light is
rivaling that of the sun (at that point), and winning.

That's bright. You can't cook with it partly because it's all one
wavelength and partly because it only hits one spot. But without
trying an experiment on my eyeballs, I can see how it could
temporarily blind you and may even cause permanent damage (especially
as your pupils probably won't contract).

Jose
--
Money: What you need when you run out of brains.
for Email, make the obvious change in the address.

On Wed, 05 Jan 2005 20:31:28 GMT, Martin Hotze
wrote:

US District Attorney Christopher J. Christie is quoted as saying:"We
have to send a clear message to the public that there is no harmless
mischief when it comes to airplanes, Mr. Banach's actions as alleged
in the criminal complaint put innocent lives at risk. That is illegal
and unacceptable." I agree with Mr. Christie.

yeah. sending out a message. like the one who was sentences to 55 years in
prison for dealing Marijuhana. yeah. sure.

I disagree with your comparison Martin. It's not the same thing.
While I agree that the sentence of 55 year in prison for dealing
Marijuana is wildly excessive for so relatively harmless a drug, it's
very hard to compare that to this case. The marijuana guy was selling
to people who wanted it. No one got inadvertantly high on it while
landing an airplane.

Sure Banach was a really dumb idiot for doing what he did. Does that
excuse him from punishment?

Corky Scott

Larry Dighera wrote:

If I'm not mistaken, coherent laser light is all in phase. Doesn't
that cause it to have more energy?

No, but it will deliver more energy in the visible spectrum, and it can be tuned
to deliver most of its energy in a very narrow band, which a typical
incandescent light source cannot.

George Patterson
The desire for safety stands against every great and noble enterprise.

On Thu, 06 Jan 2005 12:28:32 -0500, Corky Scott wrote:

I disagree with your comparison Martin. It's not the same thing.
While I agree that the sentence of 55 year in prison for dealing
Marijuana is wildly excessive for so relatively harmless a drug, it's
very hard to compare that to this case. The marijuana guy was selling
to people who wanted it. No one got inadvertantly high on it while
landing an airplane.

Sure Banach was a really dumb idiot for doing what he did. Does that
excuse him from punishment?

it depends. a punishment might be on order. but making a point by making an
example .. this seems that they will use the PATRIOT Act etc ...

#m
--
Oh. God. What have we done.

On Thu, 06 Jan 2005 17:32:43 GMT, "G.R. Patterson III"
wrote in ::

Larry Dighera wrote:

If I'm not mistaken, coherent laser light is all in phase. Doesn't
that cause it to have more energy?

No, but it will deliver more energy in the visible spectrum, and it can be tuned
to deliver most of its energy in a very narrow band, which a typical
incandescent light source cannot.

I'm way out of my depth on this subject, but this is the way I
understand the physics of coherent light verses light that is not
coherent.

Because the photons of coherent light arrive at the target at the same
time, they "pound" harder against the surface upon which they impinge
than they would if they arrived at varying times. I imagine the
physics to be similar to sonic resonance. So perhaps the photons
don't have more energy, but they have a greater effect than light that
is not coherent.



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