QUESTION:
How do the special optics make your 6 ft. KAO telescope as powerful as a 
normal 50 ft. scope?

ANSWER from Ben Burress on May 11:
This answer is quite involved and may be difficult to follow.  Perhaps 
drawing a picture of this will help.

A simple refracting telescope consists of a large convex
(converging) lens, which focuses light from celestial objects at a 
distance from the lens (the focal length) which depends on how curved 
the lens is.  A simple hand-held magnifying glass will focus
the light of the sun to a point--as you probably know--several
inches from the lens itself.  If you were to make larger and
larger magnifying glasses, you would find that the point of
focus of the light would grow farther and farther from the
lens.  If you have ever seen one of the very large refracting
telescopes at many observatories (maintained today for
mainly historical preservation, and not astronomical research),
you know how long the tube can get:  that length represents
approximately the focal length of the primary lens.

With a cassegrain reflecting telescope, light enters through
the "aperture" (the main opening, which is usually just
empty space with no glass, no lens, and no mirror).  The
light travels the distance to the primary mirror, the large
parabolic reflector at the base of the telescope "tube".  The
primary mirror both focuses the light toward a point AND
reflects the light in the opposite direction that it entered
the telescope aperture.  The light, beginning to converge,
almost reaches the aperture, but is again
reflected 180 degrees about, back toward the primary mirror.

Now it travels the length of the telescope tube for a third
time, and by the time it reaches the primary mirror again,
it has traveled a distance inside the telescope three times
the length of the telescope tube! All along this path--or
since it left the primary mirror the first time--the light
continues to converge.  When the light reaches the primary 
mirror the second time (on its way from the secondary
mirror), it would normally travel through a hole in the
middle of the primary mirror and arrive at the focal plane
(where images come into focus--and where you would put a 
sheet of photographic film or a video camera if you wanted
to take a picture), behind the primary mirror.  

On the KAO, however, there is another option, one which is used 
most of the time.  A flat mirror can be placed in front of the
primary mirror's hole and positioned diagonally so that the
light is reflected at a right angle.  Instead of proceeding
through the primary mirror, the light is directed aft,
toward the airplane's tail, through a small tunnel, and emerges 
in the airplane cabin aft of the main telescope body.  This light
travels roughly another telescope tube length to the focal plane, for a
final total of approximately four tube lengths (the actual position of the
focal plane depends on which secondary mirror is used, as we have at least
three of differing curvature). 

The astronomers' infrared detector systems and cameras are mounted at 
this position, where they have easy access to the often
tempermental instruments (tempermental because of their
complexity and sensitivity).

So, in BRIEF (too late!), due to being reflected/redirected
three times, the path the light has taken through the
telescope is at least four times the physical length of the 
telescope itself.  We have, in effect, "folded" our telescope in 
quarters.  I know that 4 x 6' is not fifty feet--but there is another 
thing that allows us to shorten the overall length the light travels 
through the telescope:  the secondary mirror.  In some reflecting 
telescopes, the secondary mirror is flat.  By using a slightly curved 
secondary mirror, we can shorten that length considerably.