Oral Presentation

Immigration History of Andromeda, Our Nearby Galactic Neighbor (Remote)

Author(s): Joan Najita

Presenter: Joan Najita (NOIRLab)

The patterns we notice in astronomical data can provide simple but valuable clues to how systems evolve and to our origins. One example can be found in observations of the Andromeda Galaxy recently obtained by DESI, the highly multiplexed multi-object spectrograph on the 4m Mayall Telescope on Kitt Peak, which reveal delicate structures---streams, wedges, and chevrons---in the positions and velocities of individual stars: evidence of a recent galactic immigration event in exquisite detail. The observations may open a window onto our past, offering a view of what our own galaxy may have looked like billions of years ago.