home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
The Starbase One Astronomy & Space Collection
/
STARBASE_ONE.ISO
/
catalog
/
lbn
/
lbn.doc
< prev
next >
Wrap
Text File
|
1991-10-03
|
7KB
|
393 lines
R-SAW-7/79-22
DOCUMENTATION FOR THE MACHINE-READABLE VERSION OF THE
LYNDS' CATALOGUE OF BRIGHT NEBULAE
July 1979
Contract NAS 5-25369
Theresa A. Nagy
Revised by:
Susan E. Gessner
Lee E. Brotzman
January 1991
Prepared for:
National Aeronautics and Space Administration
Goddard Space Flight Center
Greenbelt, Maryland 2077l
Prepared by:
Systems and Applied Sciences Corporation
68ll Kenilworth Avenue
Riverdale, Maryland 20840
TABLE OF CONTENTS
Section 1 - Introduction...............................................1-1
Section 2 - File Contents..............................................2-1
Section 3 - File Characteristics.......................................3-1
Section 4 - Remarks and Modifications..................................4-1
LIST OF TABLES
Table
2-1 File Contents....................................................2-1
3-1 File Characteristics.............................................3-1
ii
SECTION 1 - INTRODUCTION
In recent years there has been a trend away from publishing catalogues in book
form to preparing catalogues by computer and distributing them on magnetic
tape, with appearance in book form a secondary occurrence. This memo is the
result of the development of the documentation for the machine-readable version
of the catalogue and includes the basic information given in the original
preface of the published catalogue. This memo should be distributed along with
any copy of the machine-readable version of the catalogue.
1-1
SECTION 2 - FILE CONTENTS
A byte-by-byte description of the contents of the catalogue is given in Table
2-1. The information in the "Description" column is derived mainly from the
published version of the catalogue whenever possible. The "Suggested Format"
column is for FORTRAN-formatted reads.
Table 2-1. File Contents (1 of 2). LYNDS' CATALOGUE OF BRIGHT NEBULAE
Bytes Description Format
1-13 New Galactic Coordinates of the center
of the cloud
1-6 Latitude (b II) in Degrees F6.2
7 Blank 1X
8-13 Longitude (l II) in Degrees F6.2
14 Blank 1X
15-28 Equatorial Coordinates of the Center of
the Cloud (Epoch 1950.0)
Right Ascension
15-16 Hours I2
17-19 Minutes I3
20-21 Blank 2X
Declination
22 Sign Dec degrees (+/-) A1
23-24 Degrees I2
25-27 Minutes of Arc I3
28-29 Blank 2X
30-37 Dimensions of nebula as measured on the
photograph on which it appeared at its
brightest
30-33 Largest Dimension in Minutes of Arc I4
34 Blank 1X
35-37 Smallest Dimension in Minutes of Arc I3
38 Blank 1X
39-45 Area of Nebulosity in Square Degrees F7.3
46 Blank 1X
2-1
Table 2-1. File Contents (2 of 2)
Bytes Description Format
47 Color on the scale: I1
1 brighter on blue Palomar plate
2 about equal on both red and blue Palomar
plates
3 brighter on red Palomar plate
4 visible only on red Palomar plate
48 Blank 1X
49 Brightness scale with units 1 = brightest I1
to 6 = barely detectable
50 Blank 1X
51-53 Identification Number - indicates I3
whether or not the object is an isolated
region (=0) or a region of different
brightness located in a more extensive
complex of nebulosities. For example,
the entire Orion region with its many
brief areas of emission and reflection
has the identification number 73.
54 Blank 1X
55-62 Number of nebulosity if it is catalogued 8A1
in:
NGC New General Catalogue
IC Index Catalogue
S Catalogue of H II Regions, Sharpless
(1959)
C Catalogue of Diffuse Galactic Nebulae,
Cederblad (1956)
DG Dorschner and Gurtler (1963)
2-3
SECTION 3 - FILE CHARACTERISTICS
The information contained in this section is sufficient for the user to read the
machine-readable version of the catalogue. The statistics of the contents of
the entire file are given in Table 3-1.
Table 3-1. File Characteristics.
LYNDS' CATALOGUE OF BRIGHT NEBULAE
CATALOGUE.....................................................LBN
NUMBER OF FILES...............................................1
LOGICAL RECORD LENGTH.........................................62
RECORD FORMAT.................................................Fixed
TOTAL NUMBER OF LOGICAL RECORDS...............................1125
3-1
SECTION 4 - REMARKS AND MODIFICATIONS
The initial version of the machine-readable version of the Lynds' Catalogue of
Bright Nebulae was received from the University of Maryland (originally ob-
tained from the author). This catalogue was published in 1965 in the Astro-
physical Journal Supplement (#105). The initial version was sorted by galactic
longitude so that the machine-readable version would be in the same order as
the published catalogue.
4-1