Image Details
Caption: Figure 8.
Evolution of SDSS in-plane Galactic target density: target surface density of the APOGEE DR17 data release (left) and MWM’s GG survey (right) for stars within 500 pc of the Galactic midplane. The maps show a face-on schematic of the MW (credit: NASA/JPL-Caltech/R. Hurt) beneath target density contours. The Sun is located 8 kpc from the center of the Galaxy, at (X, Y = −8.0, 0.0). Light-gray contours show areas with anticipated stars at surface densities of 1 target per (100 pc)2; colored contours follow the color bar. These contours only contain stars within 500 pc of the midplane, comprising 4.7 × 105 stars in APOGEE DR17 and 1.9 × 106 stars in GG. Galactocentric target positions are calculated using Gaia DR3 photogeometric distances from C. A. L. Bailer-Jones et al. (2021).
© 2025. The Author(s). Published by the American Astronomical Society.