I haven't seen a thread on this yet, but has anyone else been reading about the series of Fast Radio Bursts (FRBs) from a galaxy 3 billion light years away?
Astronomer Telegram article
Berkeley Blog
I'm intrigued by the plots I've seen. If I'm reading them right, the bursts sweep from 8 GHz down to about 4.5 GHz over ~50 ms, and appear to be relatively narrow-band. And, of course, they're immensely powerful to be detected 3 billion light years away.
If I were a betting man, my first bet would be that it's some very rare natural phenomenon. There are a lot of galaxies within 3GLY, and many billions of stars within each galaxy, so even extremely rare phenomenon should occur pretty regularly somewhere in that volume.
My second bet would be some terrestrial event that's being inadvertently detected. There are billions of RF sources on earth, including every cell phone, microwave oven, and bluetooth device.
But for the "aliens" theory is more fun, so I've been pondering that. One article mentioned a suggestion that we were seeing spillover of some giant emitter that was being used to push or power distant probes, but if so, why would the signal be pulsed, and why the frequency sweep? Similarly, for an ordinary comm signal, I don't know why you'd sweep it like that. It could be a form of spreading, but that would suggest a very low data rate (a few hundred bps, I think) and . . . well, to my untrained eye, it doesn't look like the structure of any of our comm signals that I'm familiar with.
Radar transmissions are often "chirped," which means that the frequency sweeps up or down during the pulse, much like these FRBs. And radars are pulsed, just like these FRBs. If I have time this week*, I may try playing around with some numbers to see if I can come up with a combination of parameters (aperture, transmit power) that would give the signal strength we're seeing and be useful for doing radar images of other solar systems in the host galaxy.
When I was still a gainfully-employed satellite engineer, I had a lot of smart technical people around to bounce ideas off of, but since my retirement, there are fewer around. I think there are still some here, though, and I'd welcome any insights, speculations, corrections**, etc.
*I'm getting married on Saturday, and this sort of thing isn't high on my fiancee's priority list right now.
**I consider this to be the most likely
Astronomer Telegram article
Berkeley Blog
I'm intrigued by the plots I've seen. If I'm reading them right, the bursts sweep from 8 GHz down to about 4.5 GHz over ~50 ms, and appear to be relatively narrow-band. And, of course, they're immensely powerful to be detected 3 billion light years away.
If I were a betting man, my first bet would be that it's some very rare natural phenomenon. There are a lot of galaxies within 3GLY, and many billions of stars within each galaxy, so even extremely rare phenomenon should occur pretty regularly somewhere in that volume.
My second bet would be some terrestrial event that's being inadvertently detected. There are billions of RF sources on earth, including every cell phone, microwave oven, and bluetooth device.
But for the "aliens" theory is more fun, so I've been pondering that. One article mentioned a suggestion that we were seeing spillover of some giant emitter that was being used to push or power distant probes, but if so, why would the signal be pulsed, and why the frequency sweep? Similarly, for an ordinary comm signal, I don't know why you'd sweep it like that. It could be a form of spreading, but that would suggest a very low data rate (a few hundred bps, I think) and . . . well, to my untrained eye, it doesn't look like the structure of any of our comm signals that I'm familiar with.
Radar transmissions are often "chirped," which means that the frequency sweeps up or down during the pulse, much like these FRBs. And radars are pulsed, just like these FRBs. If I have time this week*, I may try playing around with some numbers to see if I can come up with a combination of parameters (aperture, transmit power) that would give the signal strength we're seeing and be useful for doing radar images of other solar systems in the host galaxy.
When I was still a gainfully-employed satellite engineer, I had a lot of smart technical people around to bounce ideas off of, but since my retirement, there are fewer around. I think there are still some here, though, and I'd welcome any insights, speculations, corrections**, etc.
*I'm getting married on Saturday, and this sort of thing isn't high on my fiancee's priority list right now.
**I consider this to be the most likely
via International Skeptics Forum http://ift.tt/2evATTC
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