• DOI:10.1007/978-1-4020-6933-8_26
• Corpus ID: 8522796

Resolving the Outer Disks and Halos of Nearby Galaxies

@inproceedings{Seth2007ResolvingTO,
  title={Resolving the Outer Disks and Halos of Nearby Galaxies},
  author={Anil C. Seth and Roelof de Jong and David J. Radburn-Smith and Henry Ferguson Harvard-Smithsonian CfA and Space Telescope Science Institute},
  year={2007}
}

• A. Seth, R. D. Jong, +2 authors Space Telescope Science Institute
• Published 11 October 2007
• Physics

In a hierarchical merging scenario, the outer parts of a galaxy are a fossil record of the galaxy’s early history (e.g. [1]). Observations of the outer disks and halos of galaxies thus provide a tool to study individual galaxy histories and test formation theories. Locally, an impressive effort has been made to understand the halo of the Milky Way, Andromeda, and M33 (e.g. [9, 4, 6] and contributions in this volume). However, due to the stochastic nature of halo formation, a better understanding of this process requires a large sample of galaxies with known halo properties. The GHOSTS project (PI: R. de Jong) aims to characterize the halos and outer portions of 14 nearby (D=4-14 Mpc) spiral galaxies using the Hubble Space Telescope. Figure 1 shows the type, rotation velocity and inclination of all 14 galaxies. Detection of individual stars in the outer parts of these galaxies enables us to study both the morphological properties of the galaxies, and determine the stars’ metallicity and age.