Precise fast radio burst location raises new questions

Shami Chatterjee et al. report the sub-arcsecond localization of the Arecibo-discovered fast radio burst FRB121102, the only known repeating burst source, using high-time-resolution radio interferometric observations that directly image the bursts themselves. FRBs are radio flashes of unknown physical nature with durations of milliseconds. Previous observations have lacked the resolution to uniquely identify a host or multi-wavelength counterpart. FRB121102’s localization reveals a persistent radio and optical source that is coincident with the bursts to within 100 milliarcseconds. The enigmatic persistent source could be a neutron star within its nebula in a distant host galaxy, a low-luminosity active galactic nucleus, or a previously unknown type of extragalactic source.