THE PRACTICAL ASTRONOMER
▲ Seen with naked eye, the
Full Moon will be covered
by the thickness of a pencil
held at arm’s length. The
seas may be observed,
but it is difficult to see more
detailed features. Through a small telescope
or binoculars far more detail
on the Moon’s surface
becomes visible.▼ Schmidt-Cassegrain.
A 25-cm (10-inch) Schmidt-
Cassegrain with automatic
high-speed slewing and
go-to facilities controlled
by a handset. Modern
instruments such as this
offer a high degree of
sophistication even to
beginners who can
programme the telescope
to seek out many deep-sky
objects in rapid succession.▼ Dobsonian. Lacking all
frills such as fine adjustments
for declination and right
ascension, it offers the
maximum power for
minimum outlay. For
about the same price
as an 11.5-cm (4^1 ⁄ 2 -inch)
Newtonian reflector,
significantly more power
for deep sky observations
is available with this 15-cm
(6-inch) Dobsonian. It cannot
be mechanically guided and
is unsuitable for lunar and
planetary observations.▼ Newtonian reflector.
Reflectors are readily
available and relatively
cheap. However, reflectors
with objectives less than
15 cm (6 inches) should
be avoided by those
intending to undertake
serious observing.H Atl of Univ Phil'03stp 7/4/03 6:20 pm Page 267