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We’ve been hearing a lot about FRBs lately, but we don’t know much about them. While we are learning new things every day, we’re also ‘finding’ new things every day.

According to, astronomers have actually discovered an ‘activity cycle’ in regards to more FRBs or fast radio burst for those who do not know what that stands for. FRBs are basically flashes of light that bring forth lots of energy when they arise. Now, when I say ‘lots’ I mean LOTS. 

While lots of FRBs have been discovered throughout time, where they come from or what really drives them, we don’t know for sure. A new study on one FRB in specific is quite fascinating. It was recently published in the journal Monthly Notices Of The Royal Astronomical Society and brings a lot of interesting things to the table. This study going over the FRB known as 121102. FRB 121102 seems to have a 157-day activity cycle. 

This FRB will come forth for about 90 days and then disappear for roughly 67 or so the team working on this has assessed. Research on this specific FRB was don with the Lovell Telescope and it really puts us in a direction we need to head. The more we learn about these FRBs the more we in the future may be able to uncover. 

The abstract of the pre-print of the study on this as noted above goes as follows:

The discovery that at least some Fast Radio Bursts (FRBs) repeat has ruled out cataclysmic events as the progenitors of these particular bursts. FRB 121102 is the most well-studied repeating FRB but despite extensive monitoring of the source, no underlying pattern in the repetition has previously been identified. Here, we present the results from a radio monitoring campaign of FRB 121102 using the 76-m Lovell telescope. Using the pulses detected in the Lovell data along with pulses from the literature, we report a detection of periodic behavior of the source over the span of five years of data. We predict that the source is currently ‘off’ and that it should turn ‘on’ for the approximate MJD range 59002 − 59089 (2020-06-02 to 2020-08-28). This result, along with the recent detection of periodicity from another repeating FRB, highlights the need for long-term monitoring of repeating FRBs at a high cadence. Using simulations, we show that one needs at least 100 hours of telescope time to follow-up repeating FRBs at a cadence of 0.5–3 days to detect periodicities in the range of 10–150 days. If the period is real, it shows that repeating FRBs can have a large range in their activity periods that might be difficult to reconcile with neutron star precession models.

Even Forbes touched on this topic recently and noted that this specific FRB itself was noticed back in 2014, to begin with. It as of 2016 was the only signal that had occurred in this sense more than once. While since then more repeating FRBs and things of the sort have been uncovered, it is still a very prominent one for this reason. 

Forbes wrote as follows on this topic:

Now a massive radio telescope in the U.K.—the just re-opened Jodrell Bank Observatory in Cheshire—has revealed exactly what’s going on with FRB 121102 by detecting a further 32 bursts over five years that, crucially, appear to repeat in a pattern. 

An international team led by Jodrell Bank astronomers used the iconic 76-meter Lovell Telescope, and have a new paper on their long-term radio monitoring campaign published this week in the Monthly Notices of the Royal Astronomical Society. 

The team discovered that each radio burst from FRB 121102 lasted approximately 90 days followed by a silent period of 67 days. The same behaviour then repeats every 157 days. No underlying pattern in the repetition had previously been identified, and it means astronomers are now able to predict when FRB 121102 will be “on” or “off”.

It’s an exciting clue as to the origin of FRBs.

For more information on FRBs in general take a peek at the video below. Things like this never cease to blow me away. Perhaps we’re closer to uncovering the secrets behind these FRBs than we realize.