In recent years, a new type of astronomical radio signal, known as a Fast Radio Burst (FRB), has been discovered. FRBs are extraordinarily bright flashes of radio emission that last for just a few milliseconds. They are the brightest radio signals known to come from outside our Milky Way galaxy.
Since the first FRB was discovered in 2007, there have been nearly two dozen more detected, coming from all over the sky. But their origin has remained a mystery. Now, for the first time, astronomers may have caught an FRB in the act of repeating itself – providing key clues that could help unlock the secret of what causes these strange signals.
The discovery was made by researchers using the CHIME (Canadian Hydrogen Intensity Mapping Experiment) telescope located in British Columbia, Canada. CHIME is a novel instrument designed to map out large-scale structure in the Universe using radio emissions from hydrogen gas. It is also well-suited for detecting fast transient events like FRBs.
On August 14th, 2018, CHIME observed an extremely bright FRB coming from a distant galaxy some 3 billion light-years away. This particular burst – dubbed FRB 180814 -J0422+1938 – was unusual not only because of its brightness but also because it exhibited a strange behavior never seen before: it appeared to repeat itself on six different occasions over the course of three weeks!