The Astrophysical Journal (Jan 2024)

Mapping the Milky Way in 5D with 170 Million Stars

  • Joshua S. Speagle,
  • Catherine Zucker,
  • Ana Bonaca,
  • Phillip A. Cargile,
  • Benjamin D. Johnson,
  • Angus Beane,
  • Charlie Conroy,
  • Douglas P. Finkbeiner,
  • Gregory M. Green,
  • Harshil M. Kamdar,
  • Rohan Naidu,
  • Hans-Walter Rix,
  • Edward F. Schlafly,
  • Aaron Dotter,
  • Gwendolyn Eadie,
  • Daniel J. Eisenstein,
  • Alyssa A. Goodman,
  • Jiwon Jesse Han,
  • Andrew K. Saydjari,
  • Yuan-Sen Ting,
  • Ioana A. Zelko

DOI
https://doi.org/10.3847/1538-4357/ad2b62
Journal volume & issue
Vol. 970, no. 2
p. 121

Abstract

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We present Augustus , a catalog of distance, extinction, and stellar parameter estimates for 170 million stars from 14 mag 10° drawing on a combination of optical to near-infrared photometry from Pan-STARRS, 2MASS, UKIDSS, and unWISE along with parallax measurements from Gaia DR2 and 3D dust extinction maps. After applying quality cuts, we find 125 million objects have “high-quality” posteriors with statistical distance uncertainties of ≲10% for objects with well-constrained stellar types. This is a substantial improvement over the distance estimates derived from Gaia parallaxes alone and in line with the recent results from Anders et al. We find the fits are able to reproduce the dereddened Gaia color–magnitude diagram accurately, which serves as a useful consistency check of our results. We show that we are able to detect large, kinematically coherent substructures in our data clearly relative to the input priors, including the Monoceros Ring and the Sagittarius Stream, attesting to the quality of the catalog. Our results are publicly available at doi:10.7910/DVN/WYMSXV. An accompanying interactive visualization can be found at http://allsky.s3-website.us-east-2.amazonaws.com .

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