The Signal That Repeats Every 16 Days
A Canadian radio telescope picked up flashes of radio waves from another galaxy, arriving in a pattern that repeats every 16 days.
What was reported
Fast radio bursts are flashes of radio waves lasting a few thousandths of a second, coming from far beyond our galaxy. Most are seen only once. In 2018, the CHIME telescope in British Columbia began detecting repeated bursts from one source, named FRB 20180916B.
In 2020, astronomers reported that its bursts follow a cycle: about four days of activity, then twelve days of silence, repeating every 16.35 days. The source was traced to a galaxy about 500 million light years away.
Explanations offered
Most astronomers think fast radio bursts come from magnetars, extremely magnetic neutron stars, and in 2020 one was caught producing a burst in our own galaxy. The 16-day cycle may come from the source orbiting another star or wobbling as it spins. Exactly what produces the pattern is still being studied.
- When
- Detected from 2018; pattern reported in 2020
- Where
- CHIME radio telescope, near Penticton, British Columbia, Canada
- Witnesses
- Astronomers
- Status
- Partly explained
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