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The Lynds' Bright nebulae SDB was compiled by
downloading the data from the following site,
The CDS Service for astronomical Catalogues
The CDS
FTP SITE:
http://cdsweb.u-strasbg.fr/viz-bin/Cat?VII/9
;copyright Software Bisque 2005 http://www.bisque.com
>SEARCH 57,59
>RAHOURS 21,22
>RAMINUTES 24,25
>DECSIGN 28,28
>DECDEGREES 29,30
>DECMINUTES 32,33
>MAJOR AXIS 36,39
>MINOR AXIS 41,43
>PARSE "Running Number" 1,5
>PARSE "Galactic Long/Lat" 7,12
>PARSE "Area (sq degs)" 45,51
>PARSE "Color Index" 53,53
>PARSE "Brightness scale (1-6)" 55,55
>PARSE "Identification Number" 57,59
>IDENTIFIER Lynds' Bright Nebulae
;The CDS Service for astronomical Catalogues
;http://cdsweb.u-strasbg.fr/viz-bin/qcat?lynd
>OBJECT TYPE 15
;15 = Bright Nebula
>LOADMEMORY
Because the text file has been compiled using
a field to "SEARCH" for specifically columns 57,59 as explained above, the data can be
searched in TheSky using
the find dialog (Edit | Find). You must precede the Find entry with
Lynds Bright Nebulae then enter the Lynds Bright Nebula NUMBER you wan to search for.
NOTE:
The data does not have a unique identification
number for all objects. Secondly, there are many objects that share the same ID.
This can be seen when searching the data in list form.
"0" = No ID and
Note redundancy!
The search field can be altered to
allow searching objects by there "Running Number". That is the record number if
you wish to search the objects this way.
Just change the "Search Field" to
columns 1-5 instead of columns 57-59.
Example: Edit | Find Lynds Bright Nebulae 40
returns the following:
Object name: Lynds Bright Nebulae: 40
Magnitude: 0.0
Equatorial: RA: 21h 06m 19s Dec: +49°27'05"(current)
Equatorial 2000: RA: 21h 06m 00s Dec: +49°25'00"
Horizon: Azim: 310°48'19" Alt: +30°49'49"
Transit time: 01:40 Always above horizon.
Source catalog: Sky Database: Lynds Bright Nebulae
ID: Running Number: 410
Galactic Long/Lat: 90.45
Area (sq degs): 0.001
Color Index: 3
Brightness scale (1-6): 4
Identification Number: 40
Hour angle: 05h 55m 33s
Air mass: 1.95
Sidereal time: 03:02
Click distance: 1.0000
Celestial type: 15
Index: 409
Catalog: 9
NOTE: Missing Magnitude field. There isn't a
magnitude field in the data. However, there is a field of brightness 1-6
indicating how bright the object is on a scale of 1 to 6. And,
when an object is also cross referenced to the NGC or IC catalog that magnitude
will display. Note the ALIAS field in the data cross referencing the catalog to
others.
Recompiling the data is quite
simple BECAUSE the header does all the work for you! If you wish to
change the Search field, or the order of the fields shown in the Object
Identification dialog feel free to do so.
Make any changes you want then just use Data | Import and Browse the text file
by name on your local drive and press the "COMPILE" button highlighted
below.
Warning!
See the Epoch 1950 note below.
Data | Import
Then press Compile
To label the fields use View | Display
Explorer and EXPAND the "Lynds Bright Nebula" entry under Sky Databases (SDB's) as
shown below. There you can place a check mark next to the
fields you wish to have labeled on the screen.
Pick fields you want to show
View | Display Explorer
Next make sure the "EXTENDED
LABELS" are set to "visible" AND secondly make sure the Object Type
Bright
Nebula is also enabled. View | Labels | Extended Labels for labels and
View | Display Explorer | Bright Nebula is set to visible.
Keep in mind that enabling several
fields at once clutters the screen.
View | Labels | Extended Labels
Make sure Extended labels are checked!
Also make sure Bright Nebula are visible
Check next to Bright Nebula
Lastly. Use the Display Properties for
Bright
Nebula to set the Font type, size, color, nebula fill color, etc.
See below.
View | Display Explorer | Display Properties
Choose a fill color that suits you!
The following is near M16 the
Eagle nebula in the constellation Serpens. Note the approximate size of the bright
Nebulae and their labels are shown. The running number and the original
Identification number are labeled. The Identification number is the search
field!
Wow, cool!
Blue areas are the bright nebulae
Because the data used
Epoch 1950
as described above in the field definitions section this needs to be used when
compiling the data. Using Epoch 2000 will cause a slight descripinecy in
the positions of the objects.
The size and positions of the objects in this
older dataset are prone to size errors and position errors. Also, as stated
above no magnitude is supplied with the RAW data therefore a magnitude of zero
is used.
NOTE: The RAW input data is only good at
the arcminute level! The input data does not contain arcsecond level positions,
therefore the positions of the objects will be off by several arcminutes!
Catalog Capriciousness
<---- Click here
for a complete synopsis on-line reprint of a very
informative article by Stuart Goldman of
Sky and Telescope magazine.
NGC coordinates versus
Lynds' coordinates
See the above
HEADER TEXT showing how to use these field with
the SDB header that allows immediate compiling of the text.
--------------------------------------------------------------------------------
VII/9 Lynds' Catalogue of Bright Nebulae (Lynds 1965)
================================================================================
Catalogue of bright nebulae
Lynds B.T.
<Astrophys. J. Suppl. Ser. 12, 163 (1965)>
=1965ApJS...12..163L
================================================================================
ADC_Keywords: Nebulae ; H II regions
Description:
The Catalogue of Bright Nebulae lists the galactic and equatorial
coordinates of the center of the cloud, the dimensions of the nebulae
as measured on the photograph on which it appeared at its brightest,
the area of nebulosity in square degrees, color as compared between
the blue and red Palomar plates, a brightness index on a scale of 6,
an identification number that indicates the complexity of the
nebulosity, and a cross reference to NGC (Cat. <VII.1>), Index
Catalogue (IC), Sharpless (1959) Catalogue of HII Regions (Cat.
VII/20), Cederblad (1956) Catalogue of Diffuse Galactic Nebulae,
and Dorschner and Gurtler (1963).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
× ReadMe 80 . This file
× catalog.dat 68 1125 The LBN Catalogue
--------------------------------------------------------------------------------
Byte-by-byte Description of file: catalog.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
2- 5 I4 --- Seq [1/1125]+ Running number (1)
7- 12 F6.2 deg GLON [0/360[+= Galactic longitude of cloud center
14- 19 F6.2 deg GLAT Galactic latitude of the cloud center
21- 22 I2 h RAh Hours RA, 1950.0
24- 25 I2 min RAm Minutes RA, 1950.0
28 A1 --- DE- Sign Dec, 1950.0
29- 30 I2 deg DEd Degrees Dec, 1950.0
32- 33 I2 arcmin DEm Minutes Dec, 1950.0
36- 39 I4 arcmin Diam1 Largest dimension of nebula
41- 43 I3 arcmin Diam2 Smallest dimension of nebula
45- 51 F7.3 deg2 Area Area of nebulosity
53 I1 --- Color [1/4] Color index (2)
55 I1 --- Bright [1/6] Brightness scale (3)
57- 59 I3 --- ID Identification number (4)
61- 68 A8 --- Name Other name of nebulosity (5)
--------------------------------------------------------------------------------
Note (1): This number represents the sequence in the published paper;
see also the History below.
Note (2): The following codes are used for Color:
'1' if brighter on blue Palomar plate;
'2' if equal on red and blue Palomar plates;
'3' if brighter on red Palomar plate;
'4' if visible only on the red Palomar plate.
This parameter is zero only for the two nebulae
#191 (074.53-08.42 = NGC 6960) and #844 (189.13+02.97 = IC 443)
Note (3): the brightness scale varies from '1' (brightest) to
'6' (barely detectable).
This parameter is zero only for the sane two nebulae
#191 (074.53-08.42 = NGC 6960) and #844 (189.13+02.97 = IC 443)
Note (4): ID indicates whether or not the object
is an isolated region (=0)
or a region of different brightness located in a more extensive
complex of nebulosities.
Note (5): Abbreviations are
NGC = New General Catalogue (NGC, cat. VII/1)
IC = Index Catalogue
S = Sharpless HII Regions (Sh 2-), 1959, Cat. VII/20
C = Catalogue of Diffuse Galactic Nebulae, Cederblad 1959,
Medd. Lund Ser.2, No 119
DG = Dorschner and Gurtler 1963, AN 287, 257
--------------------------------------------------------------------------------
History:
* The catalogue is extracted (in June 1994) from the CD-ROM of NASA/ADC
"Selected Astronomical Catalogs Vol. 1" with the following corrections:
- #582 (118.25+04.84) (shifted column)
- Nebulae with identical central positions where checked against
the publication and reordered according to the published catalogue.
The following galactic central positions refer to 2 or more
nebulae:
007.03-02.26 008.44+36.18 011.54+36.11 014.12+00.06
020.36-01.27 021.10-00.60 078.21+02.48 084.28-01.32
084.81+03.88 085.58+04.24 112.16+00.23 118.25+04.84
123.88-01.93 166.39-23.63 169.24-00.94 184.36-28.85
189.78-13.76 194.69-15.60 204.44-00.56 204.60-13.66
206.39-01.87 206.90-16.56 208.69-02.51 243.16+00.32
353.76+17.61
* The first "Seq" column, a number which is now found in the
literature, was added at CDS in December 1996.
References:
Cederblad, S. 1956, Medd. Lund, Ser. 2, No. 119
Sharpless, S. 1959, ApJS, 6, 257 (Catalog VII/20)
Dorschner, J., and Gurtler, J. 1963, AN, 287, 257
================================================================================
(End)
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