Poчetna     Да почнемо     To Survive in the Universe    
Inhabited Sky
    News@Sky     Астро Фотографије     Колекција     Форум     Blog New!     FAQ(Често постављана питања     Штампа     Улогуј се  

HD 2074


Садржај

Слике

Уплоадјуј своје слике

DSS Images   Other Images


Везани чланци

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).

Додај нови чланак


Линкови у сродству са темом

  • - Нема линкова -
Додај нови линк


Чланови следећих група \:


Посматрања и Астрометриски подаци

Сазвежђа:Андромеда
Ректацензија:00h25m06.45s
Deклинација:+39°02'09.2"
Apparent магнитуда:8.5
Даљина:217.391 parsecs
Proper motion RA:7.3
Proper motion Dec:-11.2
B-T magnitude:9.715
V-T magnitude:8.601

Каталог и designations:
Proper имена   (Edit)
HD 1989HD 2074
TYCHO-2 2000TYC 2783-583-1
USNO-A2.0USNO-A2 1275-00261793
HIPHIP 1984

→ Захтевај још каталога од VizieR