3:30–4:30 pm ERC 161
Host: Hsiao-Wen Chen
Rohan Naidu (MIT)
Title: The First Glimpse of the First Galaxies: A Near & Far Approach
Abstract: One of the last great unknowns in our history of the Universe is when and how the first galaxies emerged after the Big Bang. These galaxies transformed the cosmos – they illuminated the invisible scaffolding of dark matter, they ionized the intergalactic reservoirs of hydrogen, and they synthesized the elements that would one day seed life on Earth. Thanks to JWST, these enigmatic galaxies are finally coming into view. In this talk I will discuss new classes of galaxies being discovered at the highest redshifts (e.g., puzzlingly luminous systems), and novel approaches to reveal the elusive protagonists of cosmic reionization. In tandem, the Gaia mission and Milky Way surveys are unearthing some of the first galaxies buried within our own galaxy. I will show how these immigrant galaxies allow star-by-star access to the chemistry of the primordial universe, and help reconstruct the dark matter distribution of our galaxy. With this near-and-far approach, the coming few years promise a once-in-a-generation expansion of the astrophysical frontier to the brink of the Big Bang.
About speaker:
I received my PhD in Astronomy, advised by Prof. Charlie Conroy, in May 2022. My thesis was focused on identifying and understanding the immigrant galaxies the Milky Way has assimilated (“Galactic Archaeology”) using the H3 Survey and Gaia satellite. I also work on the origins of the very first galaxies (“Cosmic Dawn”) and how/when they ionized the Universe (“Cosmic Reionization”) with my undergrad adviser Prof. Pascal Oesch. I will be among the first users of the James Webb Space Telescope via two PI and two Co-I Cycle 1 programs. Starting September ‘22, I will move to the the MIT Kavli Institute as a NASA Hubble Fellow.
