Astrophysics Colloquium Maunakea Spectroscopic Explorer: The Premier 10m-class Spectroscopic Survey Observatory for the Next Decades Presented by Nicolas Flagey Canada-France-Hawaii Telescope Corporation Tuesday, December 4, 2018 11:00 A.M. in 183-328 and on Webex Abstract The Maunakea Spectroscopic Explorer (MSE) will each year obtain millions of spectra in the optical to near-infrared (360 to 1800 nm), at low (R~3000) to high (R~40000) spectral resolution by observing more than 4300 spectra per pointing via a highly multiplexed fiber-fed system. MSE is a profound transformation of the current Canada-France-Hawaii telescope and summit facilities on Maunakea, borne out as the response to the astronomical community's need for a large aperture, dedicated, spectroscopic survey facility in synergy with imaging surveys (LSST, WFIRST, ...) and giant telescopes (GMT, ELT, TMT). The project is now entering preliminary design phase after successfully completed its conceptual design. In operation, MSE will produce the same number of spectra as the SDSS Legacy Survey every 7 weeks and its flagship programs are: (1) reveal the origin of the periodic table through high spectral resolution chemical tagging of millions of stars in the Milky Way and (2) map the distribution of dark matter in the Universe and constrain its nature via radial velocity measurement of stars, star clusters, and galaxies. Given its large multiplexing capabilities and expected survey efficiency, MSE will address multiple other key aspects of astronomy, including the growth of supermassive black holes with cosmic time, the formation of large scale structures, and the tomographic mapping of the interstellar and intergalactic media. The Science Team now comprises more than 300 astronomers, a quarter of them from the U.S. community, and is currently working on a refined Detailed Science Case and a Design Reference Survey that will describe the observations to execute at first-light. In this presentation, I will summarize why MSE is the critical link within the framework of astronomical facilities of the next decades, describe the current architecture of the observatory as well as its expected performance characteristics, and conclude with an overview of the project's partnership and organization. JPL Contact: Paul Goldsmith (3-0518)   Site Manager: Webmaster: CL 08-3220