Direction of movement sun with respect to the NGP When viewed from above, i.e., looking down from the North Galactic Pole towards the South Galactic Pole, does the sun rotate clockwise or counterclockwise around the Galactic center?
Backer and Sramek 1999
observed that relative to more distant radio sources, the galactic center
Sgr A*
had a heliocentric proper motion
of about -6 milliarcseconds per year in galactic longitude.
Reid et al. 1999
reported a similar result.
Looking from NGP to SGP,
galactic longitude
increases counterclockwise, a decrease in longitude is a clockwise motion, and the Sun revolves clockwise around the galactic center.