In this talk, I will present an ongoing spectroscopic program, the Southern Stellar Stream Spectroscopic Survey (S5), which maps newly discovered stellar streams with the fiber-fed AAOmega spectrograph on the Anglo-Australian Telescope. S5 is the first systematic program pursuing a complete census of known streams in the Southern Hemisphere, providing a uniquely powerful sample for understanding the building blocks of the Milky Way’s stellar halo, the progenitors and formation of stellar streams, the mass and shape of the Milky Way’s halo, and ultimately the nature of dark matter. In additional to observing stars in the stellar streams, we use spare fibers to conduct two auxiliary programs, a Milky Way halo survey as well as a low redshift galaxy survey. In particular, we serendipitously discovered one of the fastest hyper-velocity stars in the Galaxy at ~1700 km/s, ejected from Sgr A*, the supermassive black hole in the Galactic Center.
Cody Hall, AB 107
Ting Li, Carnegie Observatories, Carnegie Institution for Science Pasadena
October 30, 2019
3:00 pm - 4:00 pm