page list

12 Feb 2020

FRB 180916



An unsolved mystery in astronomy has become even more puzzling. The source of Fast Radio Bursts (FRBs) — sudden bursts of radio waves lasting a few thousandths of a second — has remained unknown since their discovery in 2007. Observations with the Gemini North telescope of NSF’s Optical-Infrared Astronomy Research Laboratory (OIR Lab) on Maunakea in Hawai‘i, played a vital role in this discovery, which renders the nature of these extragalactic radio pulses even more enigmatic. The sources of FRBs and their nature are mysterious — many are one-off bursts but very few of them emit repeated flashes. The recently discovered FRB — identified by the unpoetic designation FRB 180916.J0158+65 — is one of only five sources with a precisely known location and only the second such source that shows repeated bursts. Such FRB’s are referred to as localized and can be associated with a particular distant galaxy, allowing astronomers to make additional observations that can provide insights into the origin of the radio pulse. Pinpointing the location of FRB 180916.J0158+65 required observations at both radio and optical wavelengths. FRBs can only be detected with radio telescopes, so radio observations are fundamentally necessary to accurately determine the position of an FRB on the sky. This particular FRB was first discovered by the Canadian CHIME radio telescope array in 2018. The new research used the European VLBI Network (EVN) to precisely localize the source, but measuring the precise distance and local environment of the radio source was only possible with follow-up optical observations with the Gemini North telescope. The international Gemini Observatory comprises telescopes in both the northern and southern hemispheres, which together can access the entire night sky. However, the source of FRB 180916.J0158+65 — which lies roughly 500 million light-years from Earth — was unexpected and shows that FRB’s may not be linked to a particular type of galaxy or environment, deepening this astronomical mystery. The researchers hope that further studies will reveal the conditions that result in the production of these mysterious transient radio pulses, and address some of the many unanswered questions they pose.