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\IBVShead{5196}{10 November 2001}

\IBVStitle{ZZ H\lowercase{yi} IS A POORLY STUDIED GALAXY}

\IBVSauth{Pastukhova, E. N.}
\IBVSinsto{Institute of Astronomy, Russian Academy of Sciences,
48, Pyatnitskaya Str., Moscow 109017, Russia}

\vskip 8mm

\IBVSabs{ZZ Hyi, classified as RR: in the 4th GCVS edition, is identical to}
\IBVSabs{the galaxy PGC 232232.}

\IBVSkey{variable stars; galaxies}
\SIMBADobj{ZZ Hyi}
\NEDobj{ZZ Hyi}

The variability of ZZ Hyi (S~6653) within 16\fmm 5 -- 17\fmm 5 pg was
announced by Hoffmeister (1963) who
had considered it a possible RR Lyrae star, difficult for investigation
because of being faint. His published declination for the star was wrong by
one degree. The star was later studied by Ge\ss ner (1981) who corrected
the declination. She gives the
variability range as 16\fmm 6 -- (17\mm, also calls the object a possible
RR Lyrae star, and presents four times of brightening.

In the course of our work on improving coordinates for all stars of the
GCVS Volume II, ZZ Hyi was confidently identified with an object in the
US Naval Observatory A2.0 catalog (Monet et al., 1998) at the following
position: 0\hr27\mm48\fsec07, --78\deg37\arcm44\farcs8 (2000.0), with the
blue and red magnitudes of 13\fmm2 and 12\fmm7, respectively. In the Hubble
Space
Telescope Guide Star Catalog (Lasker et al., 1990), this is a non-stellar
object GSC 9350.1587 (14\fmm9). We have inspected five images of the field
from large Schmidt telescopes made available by the US Naval Observatory
(USNO Pixel Server). The two images in blue light and three images in red
light show that the object is definitely non-stellar; some hints to a spiral
structure can be noticed, and the object is more compact in red light,
suggesting that it is a spiral galaxy. The brighter magnitudes in the USNO
A2.0 catalog and Guide Star Catalog compared to Sonneberg data are probably
just due to the extended appearance of the object. Its variability found
in Sonneberg cannot be real but rather reflecting variations of seeing.

The finding chart from Hoffmeister (1963) is reproduced in Fig.~1, and
the image of the field from the Digitized Sky Survey is presented in Fig.~2.

Strangely enough, we could not find the galaxy among objects studied in the
optical range and listed in the NED extragalactic data base
(http://nedwww.ipac.caltech.edu/), despite its rather high brightness.
The only object suggested by the data base within 3\arcm\ from the position
of the galaxy is the radio source PMN J0027--7838 in 1\farcm3 from it, at
nominal position 0\hr27\mm24\fsec2, --78\deg38\arcm14\arcs\ (Wright et al.,
1994).
The rather poor positional accuracy of the radio source (uncertainties of
$\sim2'$ in both coordinates) does not exclude
identification, though spiral galaxies are seldom associated with radio
sources.

We found the star in the Lyon--Meudon
(LEDA, (http://leda.univ-lyon1.fr/)) extragalactic data base as an object of
the Catalogue of Principal Galaxies (PGC, Paturel et al., 1989). It is
PGC 232232, a galaxy with integrated $B$
magnitude 16\fmm78. The LEDA data base also gives no information on
the galaxy's radial velocity.

We would like to encourage astronomers with access to southern telescopes
to verify the spiral nature of the object and to measure the galaxy's
redshift.

Thanks are due to Drs. N.~Samus and O.~Silchenko for helpful discussion,
to A.~Holl for turning my attention to the LEDA data base. Our work
on variable star catalogs is supported, in part, by grants from the Russian
Foundation for Basic Research, Russian Program of Support for Leading
Scientific Schools, anf Federal Program ``Astronomy''. I gratefully acknowledge
the use of the LEDA and NED data bases and of the US Naval Observatory Pixel
Server.

\IBVSfig{5cm}{5196-f1.eps}{A reproduction of the finding chart from
Hoffmeister (1963). South is at the top.}

\IBVSfig{5cm}{5196-f2.eps}{A DSS-II red image of the field of ZZ Hyi. South is at the top.}


\references

Ge\ss ner, H. 1981, {\it Ver\"off. Sternw.} Sonneberg, {\bf 9}, 361

Hoffmeister, C. 1963, {\it Ver\"off. Sternw.} Sonneberg, {\bf 6}, Nr. 1

Lasker, B.M.; Sturch, C. R.; McLean, B. J. et al., 1990,
{\it Astron. J.}, {\bf 99}, 2019

Monet, D.; Bird, A.; Canzian, B. et al. 1998, {\it USNO A V2.0. A Catalog of
Astrometric Standards}, US Naval Observatory (11 CD-ROMs)

Paturel, G.; Fouqu\'e, P.; Bottinelli, L.; Gouguenheim, L. 1989,
{\it Astron. Astrophys.}, Suppl. Ser., {\bf 80}, 299

Wright, A. E.; Griffith, M. R.; Burke, B. F.; Ekers, R. D. 1994, {\it Astrophys. J.}
Suppl. Ser., {\bf 91}, 111

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