Calculation of the local standard of rest from 20574 local stars in the New Hipparcos Reduction with known radial velocities

2008/12/31 by Charles Francis, Erik Anderson · 2 citations
Physics and Astronomy · #Astrophysics #Classical mechanics #Distribution (mathematics) #Galaxy #Galaxy formation and evolution #Galaxy rotation curve #Gamma-ray bursts and supernovae #Geometry #Kinematics #Mathematical analysis #Milky Way #Physics #Proper motion #RADIUS #Radial velocity #Reduction (mathematics) #Rest (music) #Rotation (mathematics) #Solar and Space Plasma Dynamics #Stars #Stellar kinematics #Stellar, planetary, and galactic studies #astro-ph

paper · pdf · doi:10.1016/j.newast.2009.03.004

12 pages, 29 figures, 4 tables. A high resolution version of this file is available from http://www.teleconnection.info/papers/LSRhires.pdf (8MB)

openalex publication_date 2009/03/27 · arxiv created 2009/03/31 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

Context. An accurate estimate of the local standard of rest (LSR) is required to determine key parameters used in approximate galactic mass models and to understand Galactic structure and evolution. However, authors are often forced to base dynamical analyses on potentially unreliable figures because recent determinations of the LSR have failed to reach agreement, especially with regard to the direction, V, of Galactic rotation. Aims. To explain why the traditional method for calculating the LSR fails, and to find alternative means of calculating the LSR with realistic error margins. Methods. We assemble and investigate the kinematic properties of 20 574 stars within 300pc, with complete and accurate kinematic data. The traditional method of calculating the LSR assumes a well-mixed distribution. In fact, the velocity distribution is highly structured, invalidating calculations based on mean motions and asymmetric drift. We find other indicators in the distribution which we believe give a better estimate of circular motion. Results. We find good agreement between results and give as our best estimate of the LSR (U₀, V₀, W₀) = (7.5 +- 1.0, 13.5 +- 0.3, 6.8 +- 0.1) km/s. We calculate the slope of the circular speed curve at the solar radius, finding -9.3 +- 0.9 km/s/kpc.

Citations

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• Distribution of CO in the Milky Way
• Chaos in models of the solar neighbourhood
• Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc--The Southern Sample
• Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data
• The Geneva-Copenhagen survey of the Solar neighbourhood
• The distribution of nearby stars in phase space mapped by Hipparcos

Cited by

• The local standard of rest and the well in the velocity distribution
• The local standard of rest from data on young objects with account for the Galactic spiral density wave