Light on earth

[Farabi]

Is light which is penetrate the earth barrier contain Ultra and infra light which is able to throught our body? I mean, something like X-ray which is able to penetrate our skin and give us a little detail under the skin?

[Rockphorr]

No, it is absorbed like warm and tan.

[FORTRANS]

Hi,

   Ultraviolet, no.  Just gives you a suntan/burn.  Infrared,
maybe.  It takes a lot of equipment and the right frequency
of infrared to lower the signal to noise ratio.  Go into a dark
room and shine a flashlight through your hand.  In the thinner
parts you can see veins (if your skin is light toned and some
veins are in the right place).

   People have used short infrared pulses and time and intensity
sensitive detectors to see a bit further into flesh.  They look for
echos of the pulses.  Ultrasound and X-rays are cheaper.

Cheers,

Steve

[dedndave]

of course there is a small amount of ultraviolet and infrared in sunlight
fortunately, most of it is "filtered out" by the protective layers of the atmosphere   :U

when you are talking about particles that penetrate the skin, you are talking about x-ray and beyond
commonly refered to simply as "radiation"
again, most of it is filtered out by the atmosphere (and the Van Halen belt -  lol)
generally speaking, the higher the frequency, the lower the level that reaches us   :P

a few neutrinos make it all the way to earth and penetrate our bodies, but don't seem to be very harmful

[FORTRANS]

a few neutrinos make it all the way to earth and penetrate our bodies, but don't seem to be very harmful

Hi Dave,

   Actually, a truly massive number of neutrinos make it to Earth
and penetrate our bodies.  (But have almost no effect.)

Cheers,

Steve N.

[MichaelW]

Maybe the neutrinos are why we don't have a much longer life span.

[dedndave]

next time Z catches me looking at a pretty girl...
..."the neutrinos made me do it, hun"   :P

[FORTRANS]

Maybe the neutrinos are why we don't have a much longer life span.

Hi,

   Only if worrying about them has an effect.  Neutrinos really do not
have much of an effect on anything.  See the following for a good
description of the first successful attempt to detect solar neutrinos.

http://www.sns.ias.edu/~jnb/Papers/Popular/Scientificamerican69/scientificamerican69.html

next time Z catches me looking at a pretty girl...
..."the neutrinos made me do it, hun"

   Try it, and let us know how well it works.

Cheers,

Steve N.

Edit:

P.S.

It is convenient to introduce a special unit to express the neutrino-capture rate in solar-neutrino experiments. The unit is the ``solar-neutrino unit,'' or SNU (which we pronounce ``snew''). One SNU equals 10^-36 capture per second per target atom. This implies that an atom of ³⁷Cl would have to wait 10³⁶ seconds, or roughly 10 billion billion times the age of the observable universe, before capturing a neutrino. Of course, in the 100,000-gallon tank, which contains about 2 x 10³⁰ atoms of ³⁷Cl, the average waiting time for a single capture when the rate of capture equals 1 SNU is only 5 x 10⁵ seconds, or about six days per capture.

SRN

[carlos]

next time Z catches me looking at a pretty girl...
..."the neutrinos made me do it, hun"   :P

how about this, " I know I was speeding, officer,  but the superluminic neutrinos were pushing my car"

:U  :U  :U

Carlos

[Farabi]

Thanks.  :U

[Rockphorr]

google(penetrating radiation)

[MichaelW]

High-energy neutrons are very penetrating. The high-energy neutrons from "neutron bombs" can reach and kill the crews of heavily armored tanks and submerged submarines. And neutron radiation tends to induce radioactivity in the materials it encounters, creating a secondary hazard.

[sinsi]

Don't forget cosmic rays, I just spent a fascinating 30 minutes on wikipedia.
One part got me

...the Intel Corporation has proposed a cosmic ray detector that could be integrated into future high-density microprocessors, allowing the processor to repeat the last command following a cosmic-ray event.

http://news.bbc.co.uk/2/hi/technology/7335322.stm


edit: This is my new excuse
customer: so why did windows blue-screen?
me: must have been a cosmic ray event.

Come to think about it, this could explain a lot...

[hutch--]

 :bg

> ..."the neutrinos made me do it, hun"

This is a formula to end up sleeping with PHIDO (the dog).  :P

[dedndave]

oh - i see you know her well   :lol