FLAT (G0): Flat Galaxy Catalog (19940306)
FILE: flat.g0 (4455 galaxies)
CONTENTS: Flat Galaxy Catalog (1993) by I.D. Karachentsev (Special Astrophysical Observatory, Zelenchukskaya, Russia); V.E. Karachentsev and S.L. Parnovsky (Astronomical Observatory of Kiev University, Kiev, Ukraine)
DATASET: This file comes in HyperSky dataset G-15, version 19940306 Availability on HyperSky CD-ROM: Vol. 2 (1995)
DESCRIPTION: This datafile contains a total of 4455 thin edge-on spiral galaxies. The catalog is the result of a systematic search of the POSS (Palomar Observatory Sky Survey) and the ESO/SERC Survey for galaxies having diameters > 40" and major-to-minor axis ratios (a/b) >= 7. The catalog and its description are published in ASTRONOMISCHE NACHRICHTEN, volume 314, 1993, number 3.
According to the authors, thin bulgeless edge-on spirals exhibit a close correlation between their linear diameter and the 21 cm line width. This correlation permits measurement of their distances without requiring detailed photometry, and makes such a catalog suitable for the study of large scale motions (cosmic streaming) and related problems in observational cosmology.
For advanced amateurs, the catalog provides a potentally rich resource of edge-on galaxy targets for CCD imaging.
DATA: The HyperSky datafile contains the following data from the catalog:
POSITION: The galaxy position for equinox 2000, precessed from the 1950 position provided in the catalog.
MAG: Magnitudes are not provided in this catalog. WARNING! Since magnitudes are not provided, all galaxies in this file will disappear if HyperSky's faint limiting faint galaxy magnitude is raised above its default. This is because HyperSky assigns the default faint limit to any galaxy without a magnitude.
Since many UGC and MCG cross-identifications are provided by the catalog (see below), users may wish to display those catalogs in conjunction with this catalog to obtain magnitudes. Both catalogs are available on the HyperSky CDROM, and individually as optional datasets.
IDENTIFICATION: For identification purposes, the catalog has been split into two complementary sections by the authors. Galaxies found on POSS plates in declination range -20 < Dec < +90 compose the original catalog, and are assigned FGC (Flat Galaxy Catalog) numbers. Galaxies found on ESO/SERC survey plates in declination range -90 < Dec < -17.5 compose the Flat Galaxy Catalog Extension, and have been given FGCE numbers. Some 200 galaxies in the declination zone common to both surveys have also been assigned FGC numbers. In all, there are 2573 FGC galaxies and 1882 FGCE galaxies. Each galaxy is identified by a number with the appropriate prefix in the HyperSky datafile.
COMMENTS: The comment lines contain the following information, provided if available for each galaxy:
* A line having the following general form:
Sxx BBB Dxd' pa=nnn
Sxx is the morphological spiral type according to the Hubble classification. (Sbc, Sdm, etc.)
BBB is a Roman numeral representing the mean surface brightness index. It ranges from I (high) to IV (very low).
Dxd gives the major and minor dimensions of the galaxy on red prints/films. Units will be arc minutes(') arc seconds(").
pa gives the position angle of the galaxy measured from North through East. Units are whole degrees.
* A line beginning with "=" giving up to 3 alternate catalog identifications (more than 3 are often provided in the catalog). Catalogs referenced in the alternate identifications include, but are not limited to, the following:
PGC - Catalog of Principal Galaxies (Paturel et al, 1989)
UGC - Uppsala Galaxy Catalog (Nilson, 1971)
MCG - Morphological Catalog of Galaxies
(Vorontsov-Veljaminov et al, 1974)
CGCG - Catalog of Galaxies & Clusters of Galaxies (Zwicky, 1968)
ESO - ESO/Uppsala Survey: ESO(B) Atlas (Lauberts, 1982)
Not all galaxies are provided with alternate identifications.
* Descriptive comments on each galaxy and its environs. Included are notes on superimposed stars, asymmetrical appearance, nearby (possibly interacting) companions, etc. These comments have been slightly edited as necessary to improve wording and/or to fit the comment into available display space. Comment length ranges from none, to single words, to multiple lines.