The Astronomical Journal
Department of Physics and Astronomy
We derive the distance to the northern extension of the Sagittarius (Sgr) dwarf spheroidal galaxy from 203 Sgr RR0 Lyrae stars found in the MACHO database. Their distances are determined differentially with respect to 288 Galactic bulge RR0 Lyrae stars also found in the MACHO data. We find a distance modulus difference of 2.41 mag at l = 5◦ and b =− 8◦ and that the extension of the Sgr galaxy toward the galactic plane is inclined toward us. Assuming R GC = 8 kpc, this implies the distance to these stars is (m − M) 0 = 16.97 ± 0.07 mag, which corresponds to D = 24.8 ± 0.8 kpc. Although this estimate is smaller than previous determinations for this galaxy and agrees with previous suggestions that Sgr’s body is truly closer to us, this estimate is larger than studies at comparable galactic latitudes.
Dartmouth Digital Commons Citation
Kunder, Andrea and Chaboyer, Brian, "Distance to the Sagittarius Dwarf Galaxy using Macho Project Rr Lyrae Stars" (2009). Dartmouth Scholarship. 2647.