Scott Kellogg sez:
>However, Traveller TL 13+ lasers are X-rays. I do not know
>exactly how transparent the atmosphere is in that range, but I
>would say that if the human body is transparent to X-rays, the
>atmosphere dang well outta be too. Thus, much less energy will
>be lost to the atmosphere than in IR to UV lasers. Less energy
>loss, the less the atmosphere will heat, therefore less beam
>diffraction.
Nope, bad analogy, bro'. The atmospheric rolloff is on both sides
of the visible range, and is orders of magnitude down from its
maximum by the time you get through the ultraviolet. They call it
the "optical window" for a reason, and they have to launch X-ray
and gamma observatories on orbiting satellites for the same reason.
>Also, when we are dealing with beams of ***250 MEGAwatts*** I
>still think yer gonna give somebody an AWFUL sunburn... Even
>*with* Sunblock 50 million! :-) Heck! Even the beam scattering
>from a 250MW laser on the ground is gonna be lethal. Think about
>it: A 250MW laser would *REALLY* light up a room... You wear
>goggles to protect your eyes from lasers of less than half a
>watt. And a 0.095milliwatt laser can damage your eye if you
>stare at it. You miss by a few meters and nobody will notice.
Nope again. You get a lot of burnoff from laser beams going through
crud like air and so on, and the release of heat on impact is ordinary
incoherent scattered light. You wear goggles to prevent accidental
coherent light impact, not scatter (although laser speckle can do
interesting things to your retinas if you stare at it for a long time).
The inverse-square law for a point source of 250MW of heat energy can
be worked out; you get a surprisingly small danger space in terms of
watts per square meter.
I would say that orbital lasers are most handy when you're dealing with
very thin or trace atmospheres, which are common in the Imperium. Above
"thin," though, you can forget it.
REFERENCE: J.D.Jackson's "Classical Electrodynamics," the book that
turns most young people off of grad school in physics.
In all fairness, when Mark Cook sez:
>consider how much X-ray energy the sun generates. We'd all be toast!),
He is also incorrect. The Sun is not a very efficient X-ray emitter;
its radiation curve peaks in the visible range. You want X-rays, you
need an O or B star, or a large A star. By the time you get down to the
F and G stars, you're peaking in the UV, visible, and IR ranges.
Mark Also sez:
>I am *green* with envy. I'd kill small populations in exchange for a
>chance to chat with Clancy. (Well, OK. Not much of a sacrifice. Some
>folks who know me suggest that I'd kill small populations just to relieve
>boredom. :^) )
I am utterly silent on this matter. Nope. Not a word. Nope.
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mike metlay (phud, no less)
[email removed]