In the past decade and a half, hundreds of Fast Radio Bursts (FRBs) have been detected by astronomers. These transient energetic bursts occur suddenly, typically last for just a few milliseconds, and are rarely seen again (except in the rare case of repeating bursts). While astronomers are still not entirely sure what causes this phenomenon, FRBs have become a tool for astronomers hoping to map out the cosmos. Based on the way radio emissions are dispersed as they travel through space, astronomers can measure the structure and distribution of matter in and around galaxies.
Using the Deep Synoptic Array (DSA) at the Owens Valley Radio Observatory (OVRO), a team of astronomers from Caltech and Cornell University used an intense FRB from a nearby galaxy to probe the halo of hot gas that surrounds the Milky Way. Their results show that our galaxy has significantly less visible (“baryonic” or “normal”) matter than previously expected. These findings support theories that matter is regularly ejected from our galaxy due to stellar winds, supernovae, and accreting supermassive black holes (SMBHs).Continue reading “Astronomers Used a Fast Radio Burst to Probe the Structure of the Milky Way”