Using the Subaru Telescope, a team of astronomers reveal the ghostly remnants of galaxy interactions in a nearby galaxy group.
Astronomers using the Subaru Telescope’s Hyper Suprime-Cam prime-focus camera recently observed the nearby large spiral galaxy M81, together with its two brightest neighbors, M82 and NGC 3077. The results of their observations are deep, super wide-field images of the galaxies and their populations of young stars. As part of a Galactic Archaeology study, the team discovered that the spatial distribution of the young stars around these galaxies follows very closely that of their distribution of neutral hydrogen. “This is the first endeavor beyond the Local Group of galaxies to demonstrate the hierarchical galaxy assembly process on galactic scales,” said team member Dr. Sakurako Okamoto (Shanghai Astronomical Observatory).
Deep and ultra wide field of view image from Hyper Suprime-Cam mounted on the Subaru Telescope including a large spiral galaxy M81, M82, dwarf galaxy Holmberg IX and NGC 3077. The research team’s analysis revealed the trace of its past interactions with the neighboring galaxies. It is exciting to see the evidence of the hierarchical galaxy assembly process at this distance beyond the Local Group of galaxies.
Publication: Sakurako Okamoto, et al. “A Hyper Suprime-Cam View of the Interacting Galaxies of the M81 Group,” 2015, ApJ, 809, L1; doi:10.1088/2041-8205/809/1/L1
PDF Copy of the Study: A Hyper Suprime-Cam View of the Interacting Galaxies of the M81 Group