NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-05-23 T10:02:19 PDT
Help | Comment | NED Home

For refcode 1999AJ....118..337C:
Retrieve 34 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by American Astronomical Society. Reproduced by permission
1999AJ....118..337C THE SOLAR MOTION RELATIVE TO THE LOCAL GROUP STEPHANE COURTEAU AND SIDNEY VAN DEN BERGH Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, National Research Council, 5071 West Saanich Road, Victoria, BC V8X 4M6, Canada Received 1999 March 4; accepted 1999 March 17 ABSTRACT New data on the membership of the Local Group (LG) are used, in conjunction with new and improved radial velocity data, to refine the derivation of the motion of the Sun relative to the LG. The Sun is found to be moving with a velocity of V = 306 +/- 18 km s^-1^ toward an apex at l = 99^deg^ +/- 5^deg^ and b = -4^deg^ +/- 4^deg^. This finding agrees very well with previous analyses, but we discuss the possibility of a bias if the phase-space distribution of LG galaxies is bimodal. The LG radial velocity dispersion is 61 +/- 8 km s^-1^. We use various mass estimators to compute the mass of the LG and the Andromeda subgroup. We find M_LG_ = (2.3 +/- 0.6) x 10^12^ M_sun_, from which M/L_V_ = 44 +/- 12 (in solar units). For an assumed LG age of 14 +/- 2 Gyr, the radius of an idealized LG zero- velocity surface is r_0_ = 1.18 +/- 0.15 Mpc. The LG is found to have 35 likely members. Only three of these have (uncertain) distances >~1.0 Mpc from the LG barycenter. Barring new discoveries of low surface brightness dwarfs, this suggests that the LG is more compact and more isolated from its surroundings than previously believed. Key words: galaxies: clusters: general-galaxies: kinematics and dynamics- galaxies: spiral-Local Group
Retrieve 34 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home