Local standard of rest

In astronomy, the local standard of rest or LSR follows the mean motion of material in the Milky Way in the neighborhood of the Sun.[1] The path of this material is not precisely circular.[2] The Sun follows the solar circle (eccentricity e < 0.1 ) at a speed of about 220 km/s in a clockwise direction when viewed from the galactic north pole at a radius of ≈ 8 kpc about the center of the galaxy near Sgr A*, and has only a slight motion, towards the Solar apex, relative to the LSR.[3][4] The LSR velocity is anywhere from 202–241 km/s.[5]

In-line references and notes

  1. ^ Frank H Shu (1982). The Physical Universe. University Science Books. p. 261. ISBN 0935702059. http://books.google.com/?id=v_6PbAfapSAC&pg=PA261. 
  2. ^ James Binney, Michael Merrifield (1998). Galactic Astronomy. Princeton University Press. p. 536. ISBN 0691025657. http://books.google.com/?id=arYYRoYjKacC&pg=PA536. 
  3. ^ Mark Reid et al. (2008). "Mapping the Milky Way and the Local Group". In F. Combes, Keiichi Wada. Mapping the Galaxy and Nearby Galaxies. Springer. pp. 19–20. ISBN 0387727671. http://books.google.com/?id=bP9hZqoIfhMC&pg=PA19. 
  4. ^ The Sun's peculiar motion relative to the LSR is 13.4 km/s. See, for example, Binney, J. & Merrifield, M.. "§10.6". op. cit.. ISBN 0691025657.  or E.E. Mamajek (2008). "On the distance to the Ophiuchus star-forming region". Astron. Nachr. AN 329: 12; §2.3. arXiv:0709.0505. Bibcode 2008AN....329...10M. doi:10.1002/asna.200710827. 
  5. ^ Steven R. Majewski1 (2008). "Precision Astrometry, Galactic Mergers, Halo Substructure and Local Dark Matter". Proceedings of IAU Symposium 248 3. arXiv:0801.4927. Bibcode 2008IAUS..248..450M. doi:10.1017/S1743921308019790. 

External links