Trigger Happy
88
whose early apotheosis was defined by the beautifully
chaotic red and green laser bolt choreography in the
film
Star Wars
(1977)—that’s wrong too. A laser is a
very tightly concentrated ray of photons that have been
lined up so they are all traveling in exactly the same
direction (unlike a normal light source, which scatters
all over the place). Like any sort of light, a laser is only
visible if it reflects off something. At a club, for
instance, the low-powered circling laser beams are
visible because they are reflecting off small particles in
the intermingled clouds of dry ice and cigarette smoke.
However, anyone who tried to smoke a cigarette in the
interstellar void would have his brains sucked out
through his face (in fact, he wouldn’t be able to light
the cigarette in the first place, owing to the lack of
oxygen). There is no dry ice, either—space is, more or
less, a vacuum. Which means there is nothing that light
can reflect off on its way to the target. Hence, lasers are
invisible, unless they are coming straight at you, in
which case you are dead.
One corollary of this, of course, is that if the
cunning enemy aliens were to build their craft with
perfectly mirrored hulls, they would be impervious to
laser attack, because the light would just bounce off
them. You’d have thought they’d have worked that one
