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Locating the celestial pole, Polar alignment, One-star polar alignment – Meade Instruments LXD 75 User Manual

Page 51: Two-star polar alignment

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Polaris

Little Dipper

Big Dipper

Cassiopeia

Fig. 42 Locating Polaris.

and also of the object you wish to locate, in a star atlas. Point the object at the bright
star. Then loosen the R.A. setting circle lock knob (

32, Fig. 1d) and turn the R.A. set-

ting circle to read the correct R.A. coordinate of the bright star; lock the R.A. setting
circle lock knob onto the object. Next, loosen the R.A. lock (

33, Fig. 1d) and turn the

telescope in R.A. to read the correct R.A. coordinate of the object. Tighten the R.A.
lock (

33, Fig. 1d). If the procedure has been followed carefully, the desired object

should now be in the telescopic field of a low-power eyepiece.

If you do not immediately see the object you are seeking, try searching the adjacent
sky area. Keep in mind that, with the 26mm eyepiece, the field of view of the

LXD75-

Series

is about 0.5°. Because of its much wider field, the viewfinder may be of signifi-

cant assistance in locating and centering objects, after the setting circles have been
used to locate the approximate position of the object.

See

USING AUTOSTAR TO FIND OBJECTS NOT IN THE LIBRARIES,

page 33, for infor-

mation on how to manually enter coordinates into Autostar.

Locating the Celestial Pole

To get basic bearings at an observing location, take note of where the Sun rises (East)
and sets (West) each day. After the site is dark, face North by pointing your left shoul-
der toward where the Sun set. To precisely point at the pole, find the North Star
(Polaris) by using the Big Dipper as a guide (

Fig. 42).

Polar Alignment

Autostar provides several different methods of Polar Alignment: Easy, One-Star, Two-
Star and Three-Star. See

EASY ALIGNMENT

, page 21, and

THREE-STAR ALIGNMENT

USING AUTOSTAR

, page 52, for those procedure.

One-Star Polar Alignment

Polar One-Star Alignment requires some knowledge of the night sky. Autostar pro-
vides a library of bright stars and one star from this library is chosen by the observer
for alignment. Polaris is chosen by Autostar. The rest of the procedure is almost iden-
tical to the

EASY ALIGNMENT

, page 21, except that Autostar prompts you to point the

telescope at Polaris and center it in the telescope's eyepiece.

Two-Star Polar Alignment

Polar Two-Star Alignment requires some knowledge of the night sky. Autostar provides
a library of bright stars and two stars from this library are chosen by the observer for
alignment. Polaris is chosen by Autostar. The rest of the procedure is almost identical
to the

EASY ALIGNMENT

, page 21, except that Autostar prompts you to point the tel-

escope at Polaris and center it in the telescope's eyepiece.