The most overdense regions of our universe today host compact conglomerations of galaxies. If we look back in time using telescopes, we can find the cosmic megastructure "babies" that will eventually mature into the galaxy clusters we see today. In a paper published to the Astrophysical Journal in November 2023, Roxana Popescu, a fifth year graduate student at UMass Amherst, investigates distant and rare protocluster candidates using observations from space telescopes like WISEand Herschel.
Studying the distant universe is extremely challenging – observing the most distant galaxies requires powerful telescopes, like the James Webb Space Telescope, owing to their extraordinary faintness. Dr. John Weaver and his team of international collaborators have been working tirelessly to classify ~60,000 galaxies, including some of the most distant known galaxies, in a paper that was published to the Astrophysical Journal Supplement Series in December 2023
Galaxies come in all different shapes and sizes and their properties dramatically evolve over cosmic time. A wide swath of these galaxies also shut down their star formation over 10 billion years ago. The lowest mass dead galaxies remain essentially unexplored at these early times, owing to their extreme faintness. In a paper submitted to the Astrophysical Journal Letters, Sam Cutler, a fifth year graduate student at UMass, uncovers two distinct classes of dead galaxies while studying the relation between galaxy size and mass using new data from the James Webb Space Telescope