Mysterious deep-space flashes repeat every 157 days
Last edited Wed Jun 10, 2020, 12:29 PM - Edit history (2)
By Mike Wall - Space.com Senior Writer 11 hours ago
The find could be a big clue about the nature of fast radio bursts.
Fast Radio Burst Reaching Earth
An artist's impression of a fast radio burst (FRB) reaching Earth, with colors signifying different wavelengths.
(Image: © Jingchuan Yu, Beijing Planetarium)
Astronomers have discovered an activity cycle in another fast radio burst, potentially unearthing a significant clue about these mysterious deep-space phenomena.
Fast radio bursts, or FRBs, are extragalactic flashes of light that pack a serious wallop, unleashing in a few milliseconds as much energy as Earth's sun does in a century. Scientists first spotted an FRB in 2007, and the cause of these eruptions remains elusive nearly a decade and a half later; potential explanations range from merging superdense neutron stars to advanced alien civilizations.
More than 100 FRBs have been discovered to date, and most of them are one-offs, flaring up just a single time (as far as we know). In January of this year, astronomers reported that one member of the "repeater" class, called FRB 180916.J0158+65, appears to exhibit a 16-day activity cycle: It fires off bursts for a four-day stretch, goes quiet for 12 days and then starts all over again.
The FRB 180916 was the first known to erupt in such a periodic way. And now scientists have spotted another.
Researchers monitored the known repeater FRB 121102 with the Lovell Telescope, a 250-foot-wide (76 meters) radio dish at Jodrell Bank Observatory in England, over the course of five years. They found strong indications of a 157-day activity cycle; 121102 seems to flare up for 90 days and then go silent for 67, the team reported in a new study.
More:
https://www.livescience.com/mysterious-fast-radio-burst-repeater.html
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Awesome! 
