Meade 4504 Observe the Moon, Lesson 6 Tracking Objects, To Polar Align the Telescope

Fig. 14: Latitude dial.

Fig. 15: Dec setting circle.

Speed 1: Fastest speed to move the telescope from one point in the sky to another.

Speeds 2 or 3: Best used for the rough centering of an object in the eyepiece.

Speeds 4 or 5: Enables the centering an object in the field of a low-to-moderate power eyepiece such as the standard H 25mm

Speeds 6 or 7: Best used for the fine centering of an object in the field of view of a high-power eyepiece such as the standard SR 4mm.

Observe the Moon

Point your telescope at the Moon (note that the Moon is not visible every night) and practice using the Arrow keys and the slew speeds to view different features. The Moon contains many interesting features, including craters, mountain ranges, and fault lines. The best time to view the Moon is during its crescent or half phase. Sunlight strikes the Moon at an angle during these periods and adds a depth to the view. No shadows are seen during a full Moon, causing the overly bright surface to appear flat and rather uninteresting. Consider the use a neutral density Moon filter when observ- ing the Moon. Not only does it cut down the Moon's bright glare, but it also enhances contrast, providing a more dramatic image.

NOTE: Do not look through the telescope's eyepiece or viewfinder while it is rapidly moving. Children should always have adult supervision while observing.

LESSON 6: Tracking Objects

As the Earth rotates beneath the night sky, the stars appear to move from East to West. The speed at which the stars move is called the sidereal rate. You can setup your telescope to move at the sidereal rate so that it automatically tracks the stars and other objects in the night sky. The tracking function automatically keeps an object more or less centered in the telescope’s eyepiece.

To automatically track objects, you must first Polar align the telescope and then select "Targets: Astronomical" from the Starfinder Setup menu.

To Polar Align the Telescope:

1.Level the mount, if necessary, by adjusting the length of the three tripod legs.

2.Release the Azimuth lock (24, Fig. 2b) of the tripod, so that the entire telescope may be rotated in a horizontal direction. Rotate the telescope until it points due North. Then re-tighten the lock. Use a compass or locate Polaris, the North Star (see Fig. 31, page 40), as an accurate reference for due North.

3.Determine the latitude of your observing location. See "APPENDIX D: HELPFUL CHARTS," page 43, for a list of latitudes of major cities around the world. Release the latitude lock (23, Fig. 2b) and tilt the telescope mount with the latitude adjustment knob (16, Fig. 2a) so that the pointer indicates the correct latitude of your viewing location on the latitude scale (Fig. 14). Re-tighten the latitude lock (23, Fig. 2b).

4Unlock the Dec Lock (27, Fig. 2b). Rotate the Optical Tube Assembly until the Dec setting circle pointer (Fig. 15) points at 90°.

5.If steps 1 through 4 above were performed with reasonable accuracy, your telescope is now sufficiently well-aligned to Polaris, the North Star, for you to begin making observations.

Once the mount has been Polar-aligned as described above, the latitude angle need not be adjusted again, unless you move to a different geographical location (i.e., a dif- ferent latitude). The only Polar Alignment procedure that needs to be performed each time you observe is to point the telescope due North, as described in step 2 above.

IMPORTANT NOTE: For almost all astronomical observing requirements, approximate settings of the telescope’s latitude and azimuth axis are acceptable. Do not allow undue attention to precise Polar Alignment of the telescope to interfere with your basic enjoyment of the instrument.

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