5.3.6  RA/DEC Coordnt. 

RA/DEC Display

Enter RA/DEC

Set Bookmark #n

GoTo Bookmark #n

5.3.6.1  RA/DEC Display 

Upon selecting "RA/DEC Display," Gemini switches to the Telescope Control Mode and 

displays the telescope's current RA and Dec. coordinates.  Then, while observing the 

display, you can move the telescope to a new position via the RA and DEC directional 

buttons.  As the telescope moves, the display will continuously change to show the new 

position. 

5.3.6.2  Enter RA/DEC 

This command allows you to enter the RA and Dec. coordinate for a point in the sky.  As 

in the previous menu item, selecting "Enter RA/DEC" displays the telescope's current RA 

and Dec. coordinates.  You can now enter a new set of coordinates by changing the 

displayed numbers. 

To enter new coordinates, navigate from digit to digit with the RA buttons and change 

their values with the Dec. buttons.  After you have completed the entry, navigate to the 

far right digit and press the RA+ button.  The new coordinates will be stored as a selected 

object that you can slew to via Gemini's GoTo function (provided the object is above the 

horizon). If Setup >Coordinate Epoch >Epoch J2000.0 was selected, the input 

coordinates are interpreted as referring to the IAU standard epoch J2000.0, and are 

precessed to the equinox of the date. As when selecting catalog objects, entering RA and 

Dec. coordinates with this function causes Gemini to display the object's hour angle (in 

minutes) and elevation (in degrees). 

5.3.6.3  Set Bookmark #n 

This menu item allows you to store as retrievable bookmarks, the coordinate position of 

up to 10 objects.  To mark the first object, center it in the telescope's field of view and 

execute "RA/DEC Coordnt

Set Bookmark #0," where 0 is the number of the first 

Bookmark.  The process can be repeated 9 more times for Bookmarks #1 to #9.  Any 

Bookmark can be overwritten by scrolling to it with the DEC buttons before setting the 

new Bookmark.   

Note:

 The bookmark does not replace the selected object, so slewing to the 

bookmarked position can only be done by executing the "GoTo Bookmark #n" menu 

item. 

5.3.6.4  GoTo Bookmark #n 

To GoTo the object at stored Bookmark #n (where n is an integer from 0 to 9), merely 

execute "RA/DEC Coordnt

GoTo Bookmark #n."  This function is exceedingly useful 

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