Inici     Començant     Sobreviure a l'Univers    
Inhabited Sky
    News@Sky     Astro Fotografia     La Col·lecció     Fòrum     Blog New!     FAQ     Premsa     Login  

HD 187760


Contingut

Imatges

Carregar la teva Imatge

DSS Images   Other Images


Articles Relacionats

Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc-The Southern Sample
We are obtaining spectra, spectral types, and basic physical parametersfor the nearly 3600 dwarf and giant stars earlier than M0 in theHipparcos catalog within 40 pc of the Sun. Here we report on resultsfor 1676 stars in the southern hemisphere observed at Cerro TololoInter-American Observatory and Steward Observatory. These resultsinclude new, precise, homogeneous spectral types, basic physicalparameters (including the effective temperature, surface gravity, andmetallicity [M/H]), and measures of the chromospheric activity of ourprogram stars. We include notes on astrophysically interesting stars inthis sample, the metallicity distribution of the solar neighborhood, anda table of solar analogs. We also demonstrate that the bimodal nature ofthe distribution of the chromospheric activity parameterlogR'HK depends strongly on the metallicity, andwe explore the nature of the ``low-metallicity'' chromosphericallyactive K-type dwarfs.

Chromospheric Ca II Emission in Nearby F, G, K, and M Stars
We present chromospheric Ca II H and K activity measurements, rotationperiods, and ages for ~1200 F, G, K, and M type main-sequence stars from~18,000 archival spectra taken at Keck and Lick Observatories as a partof the California and Carnegie Planet Search Project. We have calibratedour chromospheric S-values against the Mount Wilson chromosphericactivity data. From these measurements we have calculated medianactivity levels and derived R'HK, stellar ages,and rotation periods from general parameterizations for 1228 stars,~1000 of which have no previously published S-values. We also presentprecise time series of activity measurements for these stars.Based on observations obtained at Lick Observatory, which is operated bythe University of California, and on observations obtained at the W. M.Keck Observatory, which is operated jointly by the University ofCalifornia and the California Institute of Technology. The KeckObservatory was made possible by the generous financial support of theW. M. Keck Foundation.

Dwarf K and M stars in the southern hemisphere.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972AJ.....77..486U&db_key=AST

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:Sagittarius
Ascensió Recta:19h52m29.92s
Declinació:-23°56'57.0"
Magnitud Aparent:9.44
Distancia:28.058 parsecs
Moviment propi RA:19.5
Moviment propi Dec:-40.1
B-T magnitude:10.92
V-T magnitude:9.563

Catàlegs i designacions:
Noms Propis   (Edit)
HD 1989HD 187760
TYCHO-2 2000TYC 6891-2674-1
USNO-A2.0USNO-A2 0600-41749519
HIPHIP 97805

→ Sol·licitar més catàlegs i designacions de VizieR