Meade LX200 Telescope User Manual


 
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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 IC (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 IC 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.
The following guide to VQs was used in the visual observation
process:
SUPER Very bright object with very interesting
shape or structure.
Bright object with very interesting shape or
structure.
EXCEL OR
Very bright object with moderately
interesting shape or structure.
Bright object with moderately interesting
shape or structure.
V GOOD OR
Very bright object with little or no
interesting shape or structure.
Easy to see without averted vision with
some interesting shape or structure.
GOOD OR
Bright object, but little or no interesting
shape or structure.
FAIR Easy to see without averted vision, but little
or no interesting shape or structure.
POOR Easy to see with averted vision. Often
borderline visible without averted vision.
V POOR A struggle to see with careful use of
averted vision.
Not yet rated AND missing information for
computer estimate.
(none) OR
Could not see despite careful use of
averted vision.
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