Local standard of rest
Encyclopedia
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
. The path of this material is not precisely circular. 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. The LSR velocity is anywhere from 202–241 km/s.
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...
, the local standard of rest or LSR follows the mean motion of material in the Milky Way
Milky Way
The Milky Way is the galaxy that contains the Solar System. This name derives from its appearance as a dim un-resolved "milky" glowing band arching across the night sky...
in the neighborhood of the Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
. The path of this material is not precisely circular. 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
Solar apex
The solar apex is the direction that the Sun travels with respect to the Local Standard of Rest. In lay terms, it's the "target" within the Milky Way that the Sun appears to be "chasing" as it orbits the galaxy...
, relative to the LSR. The LSR velocity is anywhere from 202–241 km/s.