| Article in PDF |
"Peremennye Zvezdy", Prilozhenie, vol. 7, N 10 (2007) |
| ISSN 2221–0474 |
Received: 13.04.2007; accepted: 13.04.2007
(E-mail for contact: samus@sai.msu.ru)
| ||||||||||||||||||||||
Remarks: |
| The discovery of the variable star AN 1937.79 = HV 9727 was announced by
Luyten (1937), who gave the photographic magnitude range 12.0 - (16 for the
object. Sandig (1950) claimed the star to be a Mira with a tentative period of 372
days, and it got its GCVS name of DU Aqr. Hazen and Samus (1999) erroneously identified
DU Aqr with GSC 5209-00644. This identification was based on the search made by Martha
Hazen in Harvard plate stacks. She found two plates used for Luyten's discovery,
with
the position of HV 9727 marked. However, GSC 5209-00644 is a misidentification, the
star does not vary in the ASAS-3 data base and is not red. Moreover, a large field
around
it shows no objects red enough for a Mira. An attentive inspection of the photocopy
of the field of DU Aqr on the Harvard plate A9862 (October 17/18, 1909) permitted
us to
find the object really intended by Luyten to be HV 9727. It is a rather bright star-like
object (elongated like surrounding stars), missing on the second plate, A18554 (May
29/30, 1936), and below plate limits
of Moscow plates, of the POSS and similar surveys. Upon our request, the Minor Planet
Center (USA)
checked their database and revealed that the minor planet (57) Mnemosyne had been
exactly at the position of DU Aqr in 1909. We estimate the position of DU Aqr on
the plate, taken on 1909 Oct. 18.081 UT, as 21h43m21s -01d06'.2 (2000.0), and the
ephemeride
position for 1909 Oct. 18.1 UT is 21h43m20s.8 -01d06'11" (2000.0). Thus, DU Aqr does
not exist as a star, and the data in Sandig (1950) must refer to a different object.
Thanks are due to Drs. G.W. Williams and B. Marsden for their prompt and decisive help. The GCVS studies are supported, in part, by grants from the Russian Foundation for Basic Research (05-02-16289), from the Program ``Origin and Evolution of Stars and Galaxies'' of the Presidium of Russian Academy of Sciences, and from the Program of Support for Leading Scientific Schools of Russia (NSh 5290.2006.2). We acknowledge our use of ASAS-3 data. |
| References: |
| Hazen, M.L., Samus, N., 1999, Inform. Bull. Var. Stars, No. 4665
Luyten, W.J., 1937, Astron. Nachr., 263, 181 Sandig, H.-U., 1950, Astron. Nachr., 278, 181 |
|
Light Curve |