Home     Baþlangýç     Evrende yaþayabilmek için    
Inhabited Sky
    News@Sky     Gökyüzü görüntüsü     Koleksiyon     Forum     Blog New!     SSS     Basýn     Giriþ  

HD 169943


Ýçindekiler

Görüntüler

Resim Yükleyin

DSS Images   Other Images


Ýlgili Makaleler

Evidence of a Black Hole in the X-Ray Transient GS 1354-64 (=BW Circini)
We present the first radial velocity curve of the companion star to BWCir that demonstrates the presence of a black hole in this X-raytransient that recorded outbursts in 1987 and 1997 (and possibly1971-1972). We identify weak absorption features corresponding to a G0-5III donor star, strongly veiled by a residual accretion disk thatcontributes 61%-65% of the total light at 6300 Å. The Dopplermotions of these features trace an orbit of P=2.54448 days (or its 1 yralias of P=2.56358 days) and a velocity semiamplitudeK2=279+/-5 km s-1 (or K2=292+/-5 kms-1). Both solutions are equally possible. The mass functionimplied by the shorter period solution is f(M)=5.75+/-0.30Msolar, which, when combined with the rotational broadeningof the tidally locked companion (Vsini=71+/-4 km s-1), yieldsa compact object mass of M1sin3i=7.34+/-0.46 Msolar.This is substantially above the mass of a neutron star under anystandard equation of state of nuclear matter. The companion star isprobably a G subgiant that has evolved off the main sequence in order tofill its Roche lobe. Remarkably, a distance of >=27 kpc is inferredby the companion's luminosity, and this is supported by the largeobserved systemic velocity (γ=103+/-4 km s-1), whichrequires such a distance in order to be consistent with the Galacticrotation curve.

Walraven photometry of nearby southern OB associations
Homogeneous Walraven (VBLUW) photometry is presented for 5260 stars inthe regions of five nearby southern OB associations: Scorpio Centaurus(Sco OB2), Orion OB1, Canis Major OB1, Monoceros OB1, and Scutum OB2.Derived V and (B - V) in the Johnson system are included.

Radial velocities of southern stars obtained with the photoelectric scanner CORAVEL. III - 790 late-type bright stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&AS...59...15A&db_key=AST

Yeni bir Makale Öner


Ýlgili Baðlantýlar

  • - Baðlantý Bulunamadý -
Yeni Bir Baðlantý Öner


sonraki gruplarýn üyesi:


Gözlemler ve gökölçümü verileri

Takýmyýldýz:Guney Taci
Sað Açýklýk:18h29m12.90s
Yükselim:-43°50'45.0"
Görünürdeki Parlaklýk:6.36
Uzaklýk:156.986 parsek
özdevim Sað Açýklýk:1.4
özdevim Yükselim:23.2
B-T magnitude:7.492
V-T magnitude:6.451

Kataloglar ve belirtme:
Özgün isimleri   (Edit)
HD 1989HD 169943
TYCHO-2 2000TYC 7913-3301-1
USNO-A2.0USNO-A2 0450-34455454
BSC 1991HR 6915
HIPHIP 90597

→ VizieR 'den daha fazla katalog ve tanýmlama isteyin