button.  The object's designation, hour angle and elevation will be displayed, indicating 

that it has been selected. 

5.3.2.10  SAO (Smithsonian Astrophysical Observatory Catalog) 

This is a subset of the Hubble Guide Star Catalog (GSC) containing 17636 stars down to 

the 7

th

 magnitude.  To select one of them, type in its catalog number and press the RA+ 

button.  Gemini responds by confirming the object's catalog number and also its 

magnitude (e.g. "6m4" means magnitude 6.4).  Pressing the RA+ button again confirms 

the object's designation, and displays its hour angle and elevation, indicating that it has 

been selected. 

5.3.2.11 WDS (Washington Double Star Catalog) 

This is an abridged catalog containing 3989 double stars selected from the full WDS.  To 

select one of them, type in its catalog number and press the RA+ button.  If the selected 

double star is not in the database, the next available object is displayed. You can scroll 

through all of the available objects using the DEC buttons. After pressing RA+ again, the 

object's designation, hour angle and elevation will be displayed, indicating that it has 

been selected. 

5.3.2.12 GPN (Galactic and Planetary Nebulae Catalog) 

This catalog contains 1143 planetary nebulae of the Strasbourg/ESO Galactic and 

Planetary Objects Catalog (includes most objects of the Perek, Kohoutek Catalog).  To 

select one of them, type in its catalog number and press the RA+ button.  The object's 

designation, hour angle and elevation will be displayed, indicating that it has been 

selected. 

5.3.2.13 LDN (Lynd's Dark Nebulae Catalog) 

This catalog contains the 1802 dark nebulae of Lynd' s Dark Nebulae Catalog.  To select 

one of them, type in its catalog number and press the RA+ button.  The object 

s 

designation, hour angle and elevation will be displayed, indicating that it has been 

selected. 

5.3.2.14 LBN (Lynd's Bright Nebulae Catalog) 

This catalog contains the 1125 bright nebulae of Lynd' s Bright Nebula Catalog.   To 

select one of them, type in its catalog number and press the RA+ button.  The object 

s 

designation, hour angle and elevation will be displayed, indicating that it has been 

selected. 

5.3.2.15 User Defined (User Defined Catalog) 

This catalog can be built to order by downloading (and uploading) via Gemini 

s serial 

interface, the coordinates of more than 4000 objects stored on your computer.  This can 

best be accomplished using the Gemini Control Program designed by Daniel Gorlich; it 

can be downloaded from the Gemini website at 

http://www.docgoerlich.de/Rene.html

. 

Gemini Users Manual 

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