VII/192 Arp's Peculiar Galaxies (Webb 1996)
Contemporary Index Into Halton Arp's Peculiar Galaxies
Webb D.
<Sky & Telescope, 92-1, 92 (1996)>
=1996S&T....92...92W 1996S&T....92...92W
ADC_Keywords: Galaxy catalogs; Historical catalog
Description:
Halton C. Arp photographed 338 views of notable peculiar galaxies
and published them as his 1966 "Atlas of Peculiar Galaxies." Since
then, galaxy catalogs have named 585 of the involved galaxies.
This contemporary index collects names and characteristics of the
involved objects for use by contemporary observers of the historical
views.
Introduction:
The galaxies identified in Arp's Atlas of Peculiar Galaxies
represent a remarkable cross-section of observing opportunities.
With the wide availability of inexpensive CCD cameras and increasing
aperture of inexpensive commercial telescopes, more of the Arp list is
accessible to more observers. Many of the objects so catalogued were
anonymous galaxies in 1966 and have subsequently been characterized
and named. The NASA-IPAC Extragalactic Database (NED) provided most
correlations and other sources identified others. Please refer to
http://users.aol.com/arpgalaxy for further information.
File Summary:
------------------------------------------------------------------------
FileName Lrecl Records Explanations
------------------------------------------------------------------------
ReadMe 80 . This file
arpord.dat 57 338 list of Arp views with imaging data
arplist.dat 77 592 list and info for involved galaxies
------------------------------------------------------------------------
See also:
VII/74 : Atlas of Peculiar Galaxies (Arp, 1966): redshifts
Text describing arpord.dat:
This file summarizes the 338 Arp "objects" in Arp sequence. It
includes the name either of the group or the brightest galaxy
in the view. Image size and orientation were derived from Arp's
original paper. Maximum focal lengths of optical system required
to duplicate Arp's image using contemporary commercial CCD cameras
are also provided to aid the imaging observer. To find details on
the involved galaxies, use this table to locate RA and Dec and look
up the participating galaxies in arplist.dat.
Byte-by-byte Description of: arpord.dat
------------------------------------------------------------------------
bytes format units label explanations
------------------------------------------------------------------------
01-003 I3 --- Arp Arp number from original catalog
05-021 A17 --- Name *Common name (group or brightest)
22-023 I2 h RAh Right Ascension J2000 (hours)
25-029 F5.2 min RAm ? Right Ascension J2000 (minutes)
031 A1 --- DE- Declination J2000 (sign)
32-033 I2 deg DEd Declination J2000 (degrees)
35-038 F4.1 arcmin DEm Declination J2000 (minutes)
40-043 F4.1 arcmin Size *Long dimension of Arp's original photo
045 A1 --- Orient *[N,S,E,W,?] Orientation of Arp photo
47-049 I3 2.54cm fl_245 *?Focal length for CB245 CCD Camera (1)
51-053 I3 2.54cm fl_ST6 *?Focal length for SBIG ST6 CCD Camera (1)
55-057 I3 2.54cm fl_ST5 *?Focal length for SBIG ST5 CCD Camera (1)
------------------------------------------------------------------------
Note on Name:
The Name is the most common name of the brightest galaxy in the
view or the common name of the group of interacting galaxies.
Where the view is a main galaxy with companion, both names are
indicated with the companion in abbreviated form. The Right
Ascension and Declination is of the brightest galaxy and not the
center of Arp's original photo.
Note on Size:
Size is the longest dimension of the rectangular field of view of the
image published in Arp's 1966 Atlas. This information is provided
to assist the observer in framing the view for imaging.
Note on Orient:
Orientation is the alignment of the top (narrow side) of Arp's
original photo. For example, "E" means the published photo is a
rectangle with the long side running east to west with east at the
top.
Note (1):
These three columns are the focal lengths in inches of the optical
system necessary to duplicate Arp's original image using the named
CCD camera.
------------------------------------------------------------------------
Text describing arplist.dat:
This table identifies all named galaxies involved in Arp's
Atlas of Peculiar Galaxies. It is provided in Right Ascension
sequence with all of the galaxies in a given Arp view together.
Occasionally a galaxy from one Arp view will intervene between
galaxies of another Arp view, due to both Arp's location at the
same Right Ascension. Observational attributes for each such
galaxy are provided as well.
Byte-by-byte Description of: arplist.dat
------------------------------------------------------------------------
bytes format units label explanations
------------------------------------------------------------------------
01-003 I3 --- Arp Arp number from original catalog
05-020 A16 --- Name Common name of galaxy
21-024 F4.1 mag VT *?Total V-magnitude
025 A1 --- u_VT [?] Uncertain magnitude = ?
27-030 F4.1 arcmin dim1 ?Larger dimension of galaxy
031 A1 --- --- [X]
32-035 F4.1 arcmin dim2 ?Smaller dimension (if differs from dim1)
037 A1 --- u_dim2 [?] Uncertain size = ?
39-052 A14 --- MType *Morphological Type
53-055 I3 --- Uchart *?Uranometria chart number
58-059 I2 h RAh Right Ascension J2000 (hours)
61-062 I2 min RAm Right Ascension J2000 (minutes)
64-067 F4.1 s RAs Right Ascension J2000 (seconds)
069 A1 --- DE- Declination J2000 (sign)
70-071 I2 deg DEd Declination J2000 (degrees)
73-074 I2 arcmin DEm Declination J2000 (minutes)
76-077 I2 arcsec DEs Declination J2000 (seconds)
--------------------------------------------------------------------------------
Note on VT:
Magnitude sources and types vary. In general, where the galaxy
appears in Uranometria, the Deep Sky Field Guide's algorithm for
computing VT is assumed. Where the galaxy is not so listed, a variety
of magnitudes are used but not distinguished or recorded. Sources
include predominantly RC3 and PGC.
Note on MType:
Where available, the long form mixed case Hubble morphological type
(SB(rs)bc) is provided. In some cases the simplified all caps form
(IBS9P) is used. Where no such designation was available, some sources
provide a phrase like "disturbed", "DBL SYS" or "Multiple Sys".
Note on Uchart:
Galaxies listed in the Uranometria 2000.0 Deep Sky Field Guide are
indicated by reference to the chart number. Those galaxies so listed
which do not appear on the chart are field galaxies listed in the
Field Guide's notes column.
------------------------------------------------------------------------
Acknowledgments:
THIS RESEARCH MADE USE OF THE NASA/IPAC EXTRAGALACTIC DATABASE (NED)
WHICH IS OPERATED BY THE JET PROPULSION LABORATORY, CALTECH,
UNDER CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
Al Kelly computed image sizes and required focal lengths for
contemporary CCD cameras. He also photographed a few to verify that
amateur CCD cameras can see faint peculiarity.
Mike Brown loaded galaxy size information and audited the list against
the MegaStar Deep Sky Atlas database (RC3 and PGC)
Emil Bonanno precessed coordinates from epochs 1950 to 2000.
Barbara Wilson provided desire, consultation and encouragement.
Lara Lenoir audited the list against the Deep Sky Field Guide,
and MegaStar (RC3 and PGC).
Halton C. Arp for not being offended at the interest in his early work.
References:
Atlas of Peculiar Galaxies, 1966, Arp, ApJ Supp 123, Volume XIV, 1
=1966ApJS..123n...1A 1966ApJS..123n...1A
The Deep Sky Field Guide to Uranometria 2000.0, 1993, Cragin et. al.,
Willman-Bell, Inc.
(End) Dennis Webb [Johnson Space Center Astronomical Society] 19-Jul-1996