Mapping Milky Way and Local Volume Structure With LSST
Abstract
The last decade has seen a renaissance in the study of our own and other galaxies in the Local Volume, based in large part on the multi-dimensional maps provided by the vast numbers of stars cataloged by surveys such as 2MASS and SDSS. This renaissance has revolutionized our view of the Milky Way (MW) by facilitating tomographic studies of its global structure and by revealing a vast menagerie of substructures, including a new population of satellite galaxies with a millionth the luminosity of the MW and a halo replete with lumps and streams that betray the formation history of the MW. With LSST's 6 bands, 1000 epochs, and a final a limiting magnitude of r=27.6 (AB mag; 5-sigma), it will provide an excellent resource for mapping the structure and accretion history of the MW and beyond in a way that the present generation of surveys has only hinted at. LSST is anticipated to catalog 10 billion stars, including photometric abundances for the 200 million F/G stars within 100 kpc and proper motion/parallax measurements for stars brighter than r = 24 mag. Specific MW and Local Volume science to be enabled by LSST includes: mapping the 3D distribution of dust throughout the MW's disk, including variations in R_V; understanding the smooth distribution of stars in the MW and other nearby galaxies; understanding large-scale chemical gradients in the MW; discovering lumps and streams in metallicity and phase-space; inferring the mass distribution in the MW; discovering ultra-faint galaxies throughout the Local Volume as overdensities of resolved stars.
- Publication:
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American Astronomical Society Meeting Abstracts #215
- Pub Date:
- January 2010
- Bibcode:
- 2010AAS...21540110W