Improved distances and ages for stars common to TGAS and RAVE

Research output: Contribution to journalArticle


We combine parallaxes from the first Gaia data release with the spectrophotometric distance estimation framework for stars in the fifth RAVE survey data release. The combined distance estimates aremore accurate than either determination in isolation - uncertainties are on average two times smaller than for RAVE-only distances (three times smaller for dwarfs), and 1.4 times smaller than TGAS parallax uncertainties (two times smaller for giants). We are also able to compare the estimates from spectrophotometry to those from Gaia, and use this to assess the reliability of both catalogues and improve our distance estimates. We find that the distances to the lowest log g stars are, on average, overestimated and caution that they may not be reliable. We also find that it is likely that the Gaia random uncertainties are smaller than the reported values. As a by-product we derive ages for the RAVE stars, many with relative uncertainties less than 20 per cent. These results for 219 566 RAVE sources have been made publicly available, and we encourage their use for studies that combine the radial velocities provided by RAVE with the proper motions provided by Gaia. A sample that we believe to be reliable can be found by taking only the stars with the flag notification 'flag_any=0'.


  • Paul J. McMillan
  • Georges Kordopatis
  • Andrea Kunder
  • James Binney
  • Jennifer Wojno
  • Tomaž Zwitter
  • Matthias Steinmetz
  • Joss Bland-Hawthorn
  • Brad K. Gibson
  • Gerard Gilmore
  • Eva K. Grebel
  • Amina Helmi
  • Ulisse Munari
  • Julio F. Navarro
  • Quentin A. Parker
  • George Seabroke
  • Fred Watson
  • Rosemary F.G. Wyse
External organisations
  • Côte d'Azur Observatory
  • Leibniz Institute for Astrophysics Potsdam (AIP)
  • University of Oxford
  • Johns Hopkins University
  • University of Ljubljana
  • University of Sydney
  • University of Hull
  • University of Cambridge
  • Heidelberg University
  • INAF - Osservatorio Astronomico di Padova
  • University of Victoria
  • University of Hong Kong
  • University College London
  • University of Groningen
  • Australian Astronomical Observatory
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Astronomy, Astrophysics and Cosmology


  • Galaxy: fundamental parameters, Galaxy: kinematics and dynamics, Galaxy: structure, Methods: statistical
Original languageEnglish
Pages (from-to)5279-5300
Number of pages22
JournalMonthly Notices of the Royal Astronomical Society
Issue number4
Publication statusPublished - 2018 Jul 11
Publication categoryResearch