Scheme: University Research Fellowship
Organisation: University of Edinburgh
Dates: Oct 2004-Sep 2012
Summary: I am an extra-galactic astronomer who's research is focused on studying the properties of the very first galaxies to form in the earliest history of the Universe. Our current understanding suggests that the Universe formed in the Big Bang a little under fourteen billion years ago. My research is aimed at studying the first generation of galaxies which appeared around 500 million years after the Big Bang, when the Universe was only 5% of its current age. There are really two primary scientific motivations for this research. Firstly, by learning more about the physical properties of the first galaxies we will obtain information crucial to refining our understanding of how galaxies form and evolve throughout the Universe's history. Secondly, by studying the nature of the first galaxies we hope to discover if they were responsible for a fundamental change in the properties of the Universe. Around the same time that the first galaxies emerged the hydrogen gas which fills the Universe change from being entirely neutral, to being entirely ionized. The coincidence in time between the emergence of the first galaxies and this "epoch of reionization" makes it tempting to assume that the two are causally connected. However, it appears that the galaxies we have currently identified cannot provide enough energy to full reionize the Universe. At present I am trying to address this mystery by exploiting the latest data from a new camera recently installed on the Hubble Space Telescope (HST). The data which has already been provided by this new instrument has allowed us to peer deeper into the early history of the Universe than ever before, and will continue to do so over the next few years. In the longer term, the distant galaxies we identify now will be ideal targets for detailed study with the James Webb Space Telescope (due to replace HST in 2018) and the next generation of extremely large, ground-based, telescopes (ELTs) which are scheduled to be completed in around 2020.