בית     התחל מכאן     To Survive in the Universe    
Inhabited Sky
    News@Sky     תמונת אסטרו     האוסף     קבוצת דיון     Blog New!     שאלות נפוצות     עיתונות     כניסה  

HD 189825


תוכן

תמונות

הוסף תמונה שלך

DSS Images   Other Images


מאמרים קשורים

Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available

Spectral Classification of Stars in A Supplement to the Bright Star Catalogue
MK spectral types are given for about 584 stars in A Supplement to theBright Star Catalogue. These are compared with Hipparcos parallaxes tocheck the reliability of those classifications. The estimated errors are+/-1.2 subtypes, and 10% of the luminosity classes may be wrong.

Sixth Catalogue of Fundamental Stars (FK6). Part III. Additional fundamental stars with direct solutions
The FK6 is a suitable combination of the results of the HIPPARCOSastrometry satellite with ground-based data, measured over a longinterval of time and summarized mainly in the FK5. Part III of the FK6(abbreviated FK6(III)) contains additional fundamental stars with directsolutions. Such direct solutions are appropriate for single stars or forobjects which can be treated like single stars. Part III of the FK6contains in total 3272 stars. Their ground-based data stem from thebright extension of the FK5 (735 stars), from the catalogue of remainingSup stars (RSup, 732 stars), and from the faint extension of the FK5(1805 stars). From the 3272 stars in Part III, we have selected 1928objects as "astrometrically excellent stars", since their instantaneousproper motions and their mean (time-averaged) ones do not differsignificantly. Hence most of the astrometrically excellent stars arewell-behaving "single-star candidates" with good astrometric data. Thesestars are most suited for high-precision astrometry. On the other hand,354 of the stars in Part III are Δμ binaries in the sense ofWielen et al. (1999). Many of them are newly discovered probablebinaries with no other hitherto known indication of binarity. The FK6gives, besides the classical "single-star mode" solutions (SI mode),other solutions which take into account the fact that hidden astrometricbinaries among "apparently single-stars" introduce sizable "cosmicerrors" into the quasi-instantaneously measured HIPPARCOS proper motionsand positions. The FK6 gives, in addition to the SI mode, the "long-termprediction (LTP) mode" and the "short-term prediction (STP) mode". TheseLTP and STP modes are on average the most precise solutions forapparently single stars, depending on the epoch difference with respectto the HIPPARCOS epoch of about 1991. The typical mean error of anFK6(III) proper motion in the single-star mode is 0.59 mas/year. This isa factor of 1.34 better than the typical HIPPARCOS errors for thesestars of 0.79 mas/year. In the long-term prediction mode, in whichcosmic errors are taken into account, the FK6(III) proper motions have atypical mean error of 0.93 mas/year, which is by a factor of about 2better than the corresponding error for the HIPPARCOS values of 1.83mas/year (cosmic errors included).

Improved Mean Positions and Proper Motions for the 995 FK4 Sup Stars not Included in the FK5 Extension
Not Available

UBVRI photometry of FK4 and FK4 supplement stars
Photometric UBVRI observations of 172 Southern Hemisphere stars of theFK4 and FK4-Supplement catalogs, obtained using a dry-ice-cooledphotomultiplier on the 50-cm telescope at ESO on 37 nights during1982-1983 are reported. The data are presented in tables and graphs andbriefly characterized.

Four-colour UVBY and H-beta photometry of field stars - Double-lined spectroscopic binaries, G type dwarfs and early type FK4 stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&AS...29..313O&db_key=AST

הכנס מאמר חדש


לינקים קשורים

  • - לא נמצאו לינקים -
הכנס לינק חדש


משמש של הקבוצה הבאה


תצפית ומידע אסטרומטרי

קבוצת-כוכבים:נשר
התרוממות ימנית:20h02m10.56s
סירוב:-04°59'23.3"
גודל גלוי:6.718
מרחק:120.773 פארסק
תנועה נכונה:14
תנועה נכונה:-4.5
B-T magnitude:6.86
V-T magnitude:6.73

קטלוגים וכינוים:
שם עצם פרטי   (Edit)
HD 1989HD 189825
TYCHO-2 2000TYC 5168-2075-1
USNO-A2.0USNO-A2 0825-17549268
HIPHIP 98643

→ הזמן עוד קטלוגים וכינוים מוזיר