Leisure Time LX20 - Manual (Page 34)

APPENDIX D: LX200 64,359-
OBJECT LIBRARY
1. The LX200 64,359-Object Library
The LX200 64,359-Object Library is a collection of the most
studied and fantastic objects in the sky. It includes:
• 15,928 SAO (Smithsonian Astrophysical Observatory)
Catalog of Stars: All stars brighter than 7th magnitude.
• 12,921 UGC (Uppsala General Catalog) Galaxies:
Complete catalog.
• 7,840 NGC (New General Catalog) objects: Complete
Catalog.
• 5,386 1C (Index Catalog) objects: Complete catalog.
• 21,815 GCVS (General Catalog of Variable Stars) objects:
Complete catalog.
• 351 Alignment Stars: LX200 alignment stars.
• 110 M (Messier) objects: Complete catalog.
• 8 major planets from Mercury to Pluto.
This appendix has three object listings in sections 2, 3, and 4.
Section 2 (page 36) is a partial list of 278 of the best NGC objects.
These are most of the best objects in the sky, and as such, make
good first targets. Section 3 (page 43) is a list of the 250 brightest
stars and 100 double stars. The complete Messier list is shown in
Section 4 (page 49).
The above databases are accessed through the M, STAR, and
CNGC keys. The M key accesses the M object database only; the
STAR key the SAO, STAR, GCVS, and planet databases; and the
CNGC key the UGC, NGC, and 1C databases.
When the STAR or CNGC key is pressed, the display will show
which database is currently active. At this point you can enter the
object number for that database, or hit ENTER to bring up the
menu to change databases. The LX200 will remember which
database was last used.
a. SAO Catalog
The standard Star catalog used in astronomy, this catalog
includes all stars brighter than 7th magnitude.
b. UGC Catalog
This catalog of galaxies includes objects as faint as 15th
magnitude.
c. CNGC Catalog
The CNGC is enhanced from the RNGC in many ways. Angular
sizes are given in arc-seconds on the CNGC listing, and in a
convenient scaled format on the LX200 display. Magnitudes are
given to 0.1 magnitude where possible.
The coordinates in the CNGC listing are listed for the year 2000.
The LX200 calculates object positions upon power up to the
current date (as shown on the time/date display). This makes the
LX200 pointing more accurate.
Objects have been assigned a "Visual Quality Rating" (VQ). A
large number of VQs have been obtained by observing the objects.
To make the VQs as useful as possible, all observations have
been made with the same telescope and eyepiece under
substantially identical observing conditions. Only for very small
objects was a higher power eyepiece used. Your "Visual Quality
Rating" of a particular object will vary, largely due to sky
conditions.
If the object has been rated by observation, an upper-case
character (ABCDEFG) is used for the VQ on the CNGC listing. If
the object has not been observed, the VQ has been estimated by a
computer program from the object type, size, and brightness and
the VQ is specified in lower-case characters (abcdefg). The VQs
for visually-rated objects are a considerably more consistent
guide to observability and appearance than either the computed
VQs or an examination of the type, magnitude, and size data.
All, or very nearly all, of the objects in the CNGC are visible with
standard instrumentation and observing conditions used to obtain
the visual quality ratings. It is a good indication of what to expect
with similar equipment by experienced deep-sky observers in
excellent conditions. Naturally smaller telescopes and/or less
optimal observing conditions will lower the apparent quality of all
objects.
The following is a description of the format of the optional CNGC
listing for each object:
COLUMN NAME DESCRIPTION
1 CNGC# CNGC 0001 - CNGC 7840
2 RA Right Ascension
3 DEC Declination
4 SIZE Size of object (arc-seconds)
5 MAG Magnitude (-5.5 through 19.9)
6 TYPE Type of object
7 * * object is not in the RNGC
8 ALT CAT Alternate catalog name & number
9 VQ Visual Quality Rating (abcdefg ) or
(ABCDEFG)
10 TAGS Object Type # (0-F): S = Sky-Cat : T =
Tirion
11 COMMENTS Name, comments, other info
3 4
The following guide to VQs was used in the visual observation
process: