시작하기     To Survive in the Universe    
Inhabited Sky
    News@Sky     천체사진     컬렉션     포럼     Blog New!     질문및답변     출판     로그인  

HD 18264


내용

사진

사진 업로드

DSS Images   Other Images


관련 글

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).

새 글 등록


관련 링크

  • - 링크가 없습니다. -
새 링크 등록


다음 그룹에 속해있음:


관측 및 측정 데이터

별자리:화로자리
적경:02h54m41.02s
적위:-39°16'38.1"
가시등급:9.39
적경상의 고유운동:-17.5
적위상의 고유운동:-27
B-T magnitude:10.014
V-T magnitude:9.442

천체목록:
일반명   (Edit)
HD 1989HD 18264
TYCHO-2 2000TYC 7560-418-1
USNO-A2.0USNO-A2 0450-00997771
HIPHIP 13561

→ VizieR에서 더 많은 목록을 가져옵니다.