Hubble Space Telescope (HST) Treasury Program: M31-6D survey

Space Telescope Science Institute has awarded our team

  • PI  Dan Weiz
  • co-PI  Nitya Kallivayalil
  • co-PI  Andrew Wetzel
  • co-investigators:  Jay Anderson, Gurtina Besla, Mike Boylan-Kolchin, Tom Brown, James Bullock, Andrew Cole, Michelle Collins, Mike Cooper, Alis Deason, Andrew Dolphin, Aaron Dotter, Mark Fardal, Annette Ferguson, Tobias Fritz, Marla Geha, Karoline Gilbert, Raja Guhathakurta, Rodrigo Ibata, Michael Irwin, Myoungwon Jeon, Evan Kirby, Geraint Lewis, Dougal Mackey, Steve Majewski, Nicholas Martin, Alan McConnachie, Ekta Patel, Mike Rich, Josh Simon, Evan Skillman, Tony Sohn, Erik Tollerud, Roeland van der Marel

a Hubble Space Telescope (HST) Treasury Program of 244 orbits for Tracing the 6-D Orbital and Formation History of the Complete M31 Satellite SystemThese Hubble Space Telescope (HST) observations will provide the initial baselines for long-term proper-motion measurements for all of the known satellite galaxies around Andromeda (M31). Our goal is to measure the orbital motions of these satellites as they move across the sky over the next ~10 years, to complete their full 6-dimensional orbital phase-space. Our key science goals are to:

  • Understand the effect of environment on low-mass galaxy evolution
  • Use low-mass galaxies as probes of the epoch of reionization
  • Dynamically measure the mass distribution of M31’s dark-matter halo
  • Test planar associations of satellite galaxies

Combined with our existing HST Treasury Program to measure proper motions for all of the satellite galaxies of the Milky Way, we will provide proper motions for all known satellite galaxies across the Local Group.