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HD 19957


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Hipparcos red stars in the HpV_T2 and V I_C systems
For Hipparcos M, S, and C spectral type stars, we provide calibratedinstantaneous (epoch) Cousins V - I color indices using newly derivedHpV_T2 photometry. Three new sets of ground-based Cousins V I data havebeen obtained for more than 170 carbon and red M giants. These datasetsin combination with the published sources of V I photometry served toobtain the calibration curves linking Hipparcos/Tycho Hp-V_T2 with theCousins V - I index. In total, 321 carbon stars and 4464 M- and S-typestars have new V - I indices. The standard error of the mean V - I isabout 0.1 mag or better down to Hp~9 although it deteriorates rapidly atfainter magnitudes. These V - I indices can be used to verify thepublished Hipparcos V - I color indices. Thus, we have identified ahandful of new cases where, instead of the real target, a random fieldstar has been observed. A considerable fraction of the DMSA/C and DMSA/Vsolutions for red stars appear not to be warranted. Most likely suchspurious solutions may originate from usage of a heavily biased color inthe astrometric processing.Based on observations from the Hipparcos astrometric satellite operatedby the European Space Agency (ESA 1997).}\fnmsep\thanks{Table 7 is onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/397/997

Stellar uvbybeta photometry in three EUV shadow directions
We present the uvbybeta data used to locate the dust and derivedistances for nearby diffuse interstellar clouds in the EUV shadowslb27-31, lb165-32 and lb329+46 discovered by the Extreme UltravioletExplorer. The photometrically derived parallaxes of our program starsare compared to the parallaxes listed in the Hipparcos Catalog. Withinthe photometric distance limit of 150 pc, the photometric parallaxes of21 ``normal" stars are consistent with the Hipparcos measurements withinan uncertainty of 15%. Much as expected for the Str{ömgren system.Since all program stars are brighter than V~11.5 most of them areincluded in the Tycho photometry. For our sample of ~ 200 stars we findVby and V_T to be consistent. Few stars are common topublished uvbybeta catalogs, ~ 10, V and the indices compare well apartfrom beta where a zero point difference of 11 mmag is noticed.Tables \ref{tab1}-\ref{tab3} are also available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.htmlBased on observations at the European Southern Observatory, La Silla,Chile.

The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle
The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.

A Moderate-Resolution Spectral Atlas of Carbon Stars: R, J, N, CH, and Barium Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJS..105..419B&db_key=AST

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Gözlemler ve gökölçümü verileri

Takýmyýldýz:Koc
Sað Açýklýk:03h13m00.06s
Yükselim:+17°07'56.0"
Görünürdeki Parlaklýk:8.522
Uzaklýk:121.803 parsek
özdevim Sað Açýklýk:36.4
özdevim Yükselim:-10.4
B-T magnitude:9.088
V-T magnitude:8.569

Kataloglar ve belirtme:
Özgün isimleri   (Edit)
HD 1989HD 19957
TYCHO-2 2000TYC 1236-512-1
USNO-A2.0USNO-A2 1050-00858419
HIPHIP 14971

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