Home     Getting Started     To Survive in the Universe    
Inhabited Sky
    News@Sky     Astro Photo     The Collection     Forum     Blog New!     FAQ     Press     Login  

HD 181673


Contents

Images

Upload your image

DSS Images   Other Images


Related articles

Statistical Constraints for Astrometric Binaries with Nonlinear Motion
Useful constraints on the orbits and mass ratios of astrometric binariesin the Hipparcos catalog are derived from the measured proper motiondifferences of Hipparcos and Tycho-2 (Δμ), accelerations ofproper motions (μ˙), and second derivatives of proper motions(μ̈). It is shown how, in some cases, statistical bounds can beestimated for the masses of the secondary components. Two catalogs ofastrometric binaries are generated, one of binaries with significantproper motion differences and the other of binaries with significantaccelerations of their proper motions. Mathematical relations betweenthe astrometric observables Δμ, μ˙, and μ̈ andthe orbital elements are derived in the appendices. We find a remarkabledifference between the distribution of spectral types of stars withlarge accelerations but small proper motion differences and that ofstars with large proper motion differences but insignificantaccelerations. The spectral type distribution for the former sample ofbinaries is the same as the general distribution of all stars in theHipparcos catalog, whereas the latter sample is clearly dominated bysolar-type stars, with an obvious dearth of blue stars. We point outthat the latter set includes mostly binaries with long periods (longerthan about 6 yr).

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.

Submit a new article


Related links

  • - No Links Found -
Submit a new link


Member of following groups:


Observation and Astrometry data

Constellation:Pavo
Right ascension:19h28m11.01s
Declination:-73°05'26.3"
Apparent magnitude:7.044
Distance:77.7 parsecs
Proper motion RA:-0.5
Proper motion Dec:-75.8
B-T magnitude:7.33
V-T magnitude:7.068

Catalogs and designations:
Proper Names   (Edit)
HD 1989HD 181673
TYCHO-2 2000TYC 9313-1496-1
USNO-A2.0USNO-A2 0150-19048100
HIPHIP 95720

→ Request more catalogs and designations from VizieR