Inici     Sobreviure a l'Univers    
Services
    Per que Habitar     Millors Contribuents     Astro Fotografia     La Col·lecció     Fòrum     Blog New!     FAQ     Login  
→ Adopt this star  

HD 284540


Contingut

Imatges

Carregar la teva Imatge

DSS Images   Other Images


Articles Relacionats

Improved Astrometry and Photometry for the Luyten Catalog. II. Faint Stars and the Revised Catalog
We complete construction of a catalog containing improved astrometry andnew optical/infrared photometry for the vast majority of NLTT starslying in the overlap of regions covered by POSS I and by the secondincremental Two Micron All Sky Survey (2MASS) release, approximately 44%of the sky. The epoch 2000 positions are typically accurate to 130 mas,the proper motions to 5.5 mas yr-1, and the V-J colors to0.25 mag. Relative proper motions of binary components are measured to 3mas yr-1. The false-identification rate is ~1% for11<~V<~18 and substantially less at brighter magnitudes. Theseimprovements permit the construction of a reduced proper-motion diagramthat, for the first time, allows one to classify NLTT stars intomain-sequence (MS) stars, subdwarfs (SDs), and white dwarfs (WDs). We inturn use this diagram to analyze the properties of both our catalog andthe NLTT catalog on which it is based. In sharp contrast to popularbelief, we find that NLTT incompleteness in the plane is almostcompletely concentrated in MS stars, and that SDs and WDs are detectedalmost uniformly over the sky δ>-33deg. Our catalogwill therefore provide a powerful tool to probe these populationsstatistically, as well as to reliably identify individual SDs and WDs.

The Henry Draper Extension Charts: A catalogue of accurate positions, proper motions, magnitudes and spectral types of 86933 stars
The Henry Draper Extension Charts (HDEC), published in the form offinding charts, provide spectral classification for some 87000 starsmostly between 10th and 11th magnitude. This data, being highlyvaluable, as yet was practically unusable for modern computer-basedastronomy. An earlier pilot project (Roeser et al. 1991) demonstrated apossibility to convert this into a star catalogue, using measurements ofcartesian coordinates of stars on the charts and positions of theAstrographic Catalogue (AC) for subsequent identification. We presenthere a final HDEC catalogue comprising accurate positions, propermotions, magnitudes and spectral classes for 86933 stars of the HenryDraper Extension Charts.

New proper-motion stars, (fifth list)
Not Available

Enviar un nou article


Enllaços Relacionats

  • - No s'ha trobat enllaços -
Enviar un nou enllaç


Membre dels grups següents:


Dades d'Observació i Astrometria

Constel·lació:Taurus
Ascensió Recta:04h37m06.85s
Declinació:+22°17'03.3"
Magnitud Aparent:9.464
Moviment propi RA:199.5
Moviment propi Dec:-4.5
B-T magnitude:10.352
V-T magnitude:9.538

Catàlegs i designacions:
Noms Propis
HD 1989HD 284540
TYCHO-2 2000TYC 1278-358-1
USNO-A2.0USNO-A2 1050-01336649
HIPHIP 21503

→ Sol·licitar més catàlegs i designacions de VizieR