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Care and maintenance – Orion SPACEPROBE 9851 User Manual

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brightest deep-sky objects, first catalogued about 200 years
ago by the French astronomer Charles Messier.
Determine in which constellation the object lies. Now, find the
constellation in the sky. If you do not recognize the constella-
tions on sight, consult a planisphere. The planisphere gives
an all-sky view and shows which constellations are visible on
a given night at a given time.
Now, look at your star chart and find the brightest star in the
constellation that is near the object you are trying to find.
Using the finder scope, point the telescope at this star and
center it on the crosshairs. Next, look again at the star chart
and find another suitably bright star near the bright star cur-
rently centered in the finder. Keep in mind that the field of
view of the finder scope is 7°, so you should choose another
star that is no more that 7° from the first star, if possible.
Move the telescope slightly, until the telescope is centered
on the new star.
Continue using stars as guideposts in this way until you are
at the approximate position of the object you are trying to
find (Figure 14). Look in the telescope’s eyepiece, and the
object should be somewhere within the field of view. If it’s
not, sweep the telescope carefully around the immediate
vicinity until the object is found.
If you have trouble finding the object, start the starhop again
from the brightest star near the object you wish to view. This
time, be sure the stars indicated on the star chart are in fact
the stars you are centering in the eyepiece. Remember, the
finder scope (and main telescope eyepiece, for that matter)

gives an inverted image, so you must keep this in mind when
star hopping from star to star.

8. Care and Maintenance

If you give your telescope reasonable care, it will last a
lifetime. Store it in a clean, dry, dust-free place, safe from
rapid changes in temperature and humidity. Do not store the
telescope outdoors, although storage in a garage or shed is
OK. Small components like eyepieces and other accessories
should be kept in a protective box or storage case. Keep the
caps on the front of the telescope and on the focuser draw-
tube when it is not in use.
Your SpaceProbe 130mm EQ telescope requires very little
mechanical maintenance. The optical tube is steel and has
a smooth painted finish that is fairly scratch-resistant. If a
scratch does appear on the tube, it will not harm the tele-
scope. If you wish, you may apply some auto touch-up paint
to the scratch. Smudges on the tube can be wiped off with
a soft cloth and a household cleaner such as Windex or
Formula 409.

Cleaning lenses
Any quality optical lens cleaning tissue and optical lens clean-
ing fluid specifically designed for multi-coated optics can
be used to clean the exposed lenses of your eyepieces or
finder scope. Never use regular glass cleaner or cleaning fluid
designed for eyeglasses. Before cleaning with fluid and tissue,
however, blow any loose particles off the lens with a blower
bulb or compressed air. Then apply some cleaning fluid to a
tissue, never directly on the optics. Wipe the lens gently in a
circular motion, then remove any excess fluid with a fresh lens
tissue. Oily fingerprints and smudges may be removed using
this method. Use caution; rubbing too hard may scratch the
lens. On larger lenses, clean only a small area at a time, using
a fresh lens tissue on each area. Never reuse tissues.

Cleaning Mirrors
You should not have to clean your telescope’s mirrors very
often; normally once every year or so. Covering your tele-
scope when it is not in use will prevent dust from accumu-
lating on the mirrors. Improper cleaning can scratch mirror
coatings, so the fewer times you have to clean the mirrors,
the better. Small specks of dust or flecks of paint have virtu-
ally no effect on the visual performance of the telescope.
The large primary mirror and the elliptical secondary mirror
of your telescope are front-surface aluminized and over-
coated with hard silicon dioxide, which prevents the alumi-
num from oxidizing. These coatings normally last through
many, many years of use before requiring re-coating (which
is easily done).
To clean the secondary mirror, remove the mirror in its holder
from the 4-vaned spider in the tube. Do this by grasping the
secondary mirror holder with your fingertips while turning the
central screw on the spider’s central hub counterclockwise.
handle the mirror holder only; do not touch the mirror surface.
Also be sure not to lose the spring behind the mirror holder.

Figure 14.

Star hopping is a good way to locate hard-to-find

objects. Refer to a star chart to map a route to the object that uses
bright stars as guideposts. Center the first star you’ve chosen
in the finder scope and telescope eyepiece (1). Now move the
scope carefully in the direction of the next bright star (2), until it
is centered. Repeat (3 and 4). The last hop (5) should place the
desired object in the eyepiece.