Mean secular parallax at low galactic latitude

Abstract

view Abstract Citations (36) References (55) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Mean secular parallax at low galactic latitude. Stone, R. C. Abstract Very accurate relative proper motions are determined for 1332 stars in 62 regions at very low galactic latitude (less than 10 deg in absolute value). These data are supplemented with 27 additional regions of proper motions of faint stars in the directions of open clusters, and a statistical analysis of all these motions is performed to determine the position of the solar apex for faint stars and to calibrate the mean secular parallax at low galactic latitude. It is found that the apex for faint stars is near the basic solar apex and that the parallax calibration confirms the smaller values previously obtained on the basis of a much smaller sample of proper-motion regions. This calibration is used to determine the peculiar space motions of O stars in the solar neighborhood, from which motions are computed the semimajor axes and vertex direction of the O-star velocity ellipsoid. The results show that the vertex direction is into the fourth velocity quadrant, that 20% of the O stars are runaways, and that most O stars were probably born near the galactic plane. Publication: The Astronomical Journal Pub Date: April 1978 DOI: 10.1086/112215 Bibcode: 1978AJ.....83..393S Keywords: Astrometry; Parallax; Star Clusters; Star Distribution; Stellar Motions; Least Squares Method; O Stars; Open Clusters; Photoelectric Emission; Radial Velocity; Stellar Luminosity; Astronomy; Faint Stars:Proper Motions; O Stars:Runaway Stars; Solar Apex full text sources ADS | data products SIMBAD (64)