59
Appendix E
are acceptable. Do not allow undue attention to precise polar
alignment of the telescope to interfere with your basic enjoyment
of the instrument.
Note:
The Meade equatorial wedge is designed solely for use in
conjunction with your Meade tripod. The wedge should never be
used without the tripod (e.g., by placing the wedge alone on a
table top and then mounting the telescope on the wedge—the
wedge may become seriously unbalanced, to the point where the
telescope may actually tip over.
Lining Up with the Celestial Pole
Objects in the sky appear to revolve around the celestial pole.
(Actually, celestial objects are essentially “fi xed”. Their apparent
motion is caused by the Earth’s rotation). During any 24 hour
period, stars make one complete revolution about the pole,
making concentric circles with the pole at the center. By lining
up the telescope’s polar axis with the North Celestial Pole (or
for observers located in Earth’s Southern Hemisphere, with the
South Celestial Pole), astronomical objects may be followed, or
tracked, simply by moving the telescope about one axis, the polar
axis. This tracking may be accomplished automatically with the
LX600 ACF electric motor drive.
If the telescope is reasonably well aligned with the pole, very
little use of the telescope’s Declination slow motion control is
necessary. Virtually all of the required telescope tracking will be
in Right Ascension. (If the telescope were perfectly aligned with
the pole, no Declination tracking of celestial objects would be
required.) For the purposes of casual telescopic observations,
lining up the telescope’s polar axis to within a degree or two
of the pole is more than suffi cient: with this level of pointing
accuracy, the telescope’s motor drive will track accurately and
keep objects in the telescopic fi eld of view for perhaps 20 to 30
minutes.
Begin polar aligning the telescope by locating Polaris. Finding
Polaris is simple. Most people recognize the “Big Dipper”. The
Big Dipper has two stars that point the way to Polaris (
Fig. 23
).
Once Polaris is found, it is a straightforward procedure to obtain
a rough polar alignment.
To line up with Polaris, follow the procedure described below.
Refer to the instruction sheet included with your equatorial wedge
for information about attaching the wedge to the telescope and
also about using the azimuth and latitude controls.
1.
Select “Setup: Telescope” from the AutoStar
II menus. Press ENTER. Scroll to “Telescope:
Mount” and press ENTER. Scroll to “Scope
Mounting: Polar” and press ENTER. The
telescope mount is now set to the polar mode.
2.
Press MODE until “Select Item: Setup” displays.
Press ENTER. “Setup: Align” displays. Press
ENTER. “Align: Easy” displays. Scroll to “Align:
One-Star” and press ENTER. AutoStar II now
prompts you to set the telescope in the polar
home position.
a.
Using the bubble level placed on the wedge
fl oor, adjust the tripod legs so that the bubble
is level.
b.
Set the wedge to your observing latitude.
c.
Using the Up and Down Arrow keys, rotate
the telescope tube in Declination so that the
telescope’s Declination reads 90°.
See SETTING
CIRCLES, page 58
.
Tip:
You can check if the declination is set at true 90°. Look
through the eyepiece and rapidly move the optical tube on the
R.A. axis. If all the stars rotate around the center of the fi eld of
view, the Declination is set at 90°. If the stars arc out of the fi eld
of view, move the optical tube on the Declination axis until you
achieve the centering effect.
d.
Loosen the RA lock, and rotate the fork arms
to the 00 position H. A. : Move the forks arms
Fig. 22.
Optional X-Wedge for equatorial mode.
Fig. 23.
Locating Polaris
