Pushing the boundaries of faint galaxies science


Michael Jones

The faintest galaxies in the Universe provide a vital stress test of models of galaxy formation and cosmology as they are the lowest mass galaxies that succeed in forming stars, as well as being the most dark matter-dominated. Until recently the faintest galaxies could only be identified within the Local Group where interactions with the Milky Way and M31 are a confounding factor in understanding their history. Cosmic reionization is thought to shut off star formation in these galaxies, but some recent discoveries at the edge of the Local Group have called this into question. The depth that Rubin/LSST imaging will provide will open a floodgate for new discoveries in the low-mass, low surface brightness regime. However, more can still be learned from existing imaging surveys that will help LSST reach its maximum potential in the discovery space of the faintest extra-galactic objects. Using a range of existing ground-based imaging surveys in combination with both machine learning and citizen science approaches, we are pushing the boundaries of searches for the faintest galaxies into the semi-resolved regime and searching for enigmatic types of objects for which few known examples exist. In this talk I will provide an overview of our approach and the types of objects we have uncovered that were missed by other established searches, as well as some lessons learned that can be applied to the next generation of surveys with Rubin.


This talk will be given in the The Rubin Galaxies Science Collaboration session.


Career Stage: 
Post Doc