Meade LX90GPS instruction manual Astronomical Observing, To Track an Object Automatically

Definition: Initialization is a pro- cedure that ensures that AutoStar operates correctly. When you first use AutoStar, it doesn't yet know where the observation location site is or the time or date of the observation session.

During the automatic alignment procedure, the system calculates these parameters automatically.

AutoStar uses this information to precise- ly calculate the loca- tion of celestial objects (such as stars and planets) and to move your telescope cor- rectly for various oper- ations.

Important Note:

Press any key on the AutoStar handbox to abort the GPS fix.

Press MODE repeat- edly until "Select Item" displays and use the AutoStar menu options to choose a manual alignment or to find an AutoStar option, such as "Brightness."

Astronomical Observing

Used as an astronomical instrument, your telescope has many optical and electromechanical capabilities. It is in astronomical applications where the high level of optical performance is readily visible. The range of observable astronomical objects is, with minor qualification, limited only by the observer’s motivation.

To Track an Object Automatically

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. If the telescope is not tracking an astronomical object, the object will drift out of the eyepiece field of view. The tracking function automatically keeps an object more or less centered in the telescope’s eyepiece.

To automatically track objects, you must initialize AutoStar, and then select "Targets: Astronomical" from the AutoStar Setup menu. You must also learn how the AutoStar keypad operates in order to move through the AutoStar menus.

Moving Through AutoStar’s Menus

The AutoStar database is organized in levels for quick and easy navigation.

•Press ENTER to go deeper into AutoStar's menu levels.

•Press MODE to move back toward the top menu level.

•Press the Scroll keys to move up and down through the options available for each level.

•Press the Arrow keys to enter characters and digits.

The Arrow keys are also used to move the telescope.

Automatic Alignment Feature (Auto Align™)

AutoStar offers four methods of altazimuth (alt/az) alignment; this section describes how to ini- tialize and align your telescope using Automatic Alignment. (For a description of the other alt/az alignment methods, see pages 38 and 39. For information about equatorial (polar) align- ment, see APPENDIX A, page 50.)

To prepare your telescope for Automatic Alignment:

1.Tighten the R.A. and Dec. locks (9 and 6, Fig. 1).

2.Verify that AutoStar is properly connected to your telescope. See HOW TO ASSEMBLE YOUR TELESCOPE, page 13.

3.Flip the telescope power switch to the ON position.

When you slide the On/Off switch to “On” on your telescope’s computer control panel, a version screen briefly appears, followed by “Welcome to AutoStar.”

4.“Press 0 to align or Mode for Menu.” displays. Press “0” to begin Automatic Alignment. (If you wish to choose a manual alignment method, keep pressing Mode to go through the menus to find other alignments.)

Note: AutoStar initializes the Smart Drive if "On" has been previously performed PEC training and you have "parked" the telescope. If you have parked it, AutoStar will remember its position on the worm gear. If you do not park the scope and turn it off, it will not remember its position. See PARK, page 28 and PEC TRAINING, page 54.

5."Automatic Alignment" displays. The system now performs the following routines (press any AutoStar key to abort Automatic Alignment; see IMPORTANT NOTE, at the left) :

Caution: As the telescope performs the following operations, it will swing and rotate. Keep a safe distance from the telescope. The telescope now finds the level and tilt posi- tion of the telescope, and also detects where true North is. It may not actually level or tilt the telescope or point to North—it is just detecting these positions. This make take a minute or two.

a.Detects “level” of the base of the telescope; finds tilt and tip. To detect level, AutoStar must calculate "level" at three compass points. See FINDING TRUE LEVEL in on page 21.

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