The Final Frontier: Galaxies at the Epoch of Reionization
When did galaxies start forming stars? What is the role of distant galaxies in galaxy formation models and the epoch of reionization? What are the conditions in typical low-mass, star-forming galaxies at z ∼ 6 and above? Recent observations with HST and Spitzer indicate several critical puzzles in studies that address these questions. Chief among those – galaxies – might have started forming stars earlier than previously thought (< 400 Myr after the Big Bang). Their star formation history differs from what is predicted from simulations. I will present the latest results from our deep HST and Spitzer surveys showing successful measurements of the properties of stellar populations and identifying new puzzles facing future surveys at z ∼ 7 and beyond.