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Astronomers detect regular rhythm of radio waves, with origins unknown

news.mit.edu

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Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#31

Post by CuriouslyC »

DrBazza wrote: post #21

If it's periodic, it's something orbiting something. If it's powerful enough to be seen 500 million ly away, one of the two orbiting objects is going to be a black hole.

Maybe, but perhaps not in the way you think. A source that emits radiation only at certain angles (think a stellar disco ball) would only "flash" us infrequently as we moved relative to it.

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#33

Post by teraflop »

savrajsingh wrote: post #9

They didn’t mention a simpler solution: random emitter orbits behind something / Is occluded for the silent period?

I'm having a hard time imagining what kind of geometry would cause an orbiting object to be occluded for more than 50% of its orbital period.

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#35

Post by Supermancho »

bawana wrote: post #15

If aliens did exist, they would probably compress their communications. And they might use a fault tolerant infrastructure like TCP/IP. In either scenario, real communications would not be periodic but closer to random noise. Has anyone performed a Zipf plot or calculated shannon entropy of non-periodic radio signals?

TCP over radio? Direct communication by is the simplest implementation. Encoding a signal further seems counter intuitive, as opposed to a short repeating beacon that serves initial groundwork for a handshake. If the signal is supposed to cross vast interruptible distance, the bodies interrupting a continuous straightforward signal would appear periodic to the receiver.

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#36

Post by JJMcJ »

zoomablemind wrote: post #17
abc_lisper wrote: post #13

Earlier quoted context omitted.

Until one day when it becomes true ..

We should beam back our commercials at them... they may just change their mind and switch to ads-free alternative.

"Earth Peoples, we come for the secret of the ShamWow"

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#37

Post by teraflop »

squarefoot wrote: post #26

Shouldn't they be able to discriminate the type of object (single star with orbiting planets that obstruct radio waves, or dual star plus planets where the emitter itself also moves around an orbit) by analyzing the received carrier frequency and see if it's also modulated by a much lower frequency (Doppler effect) compatible with orbital motion?

FRBs don't really have a "carrier frequency" in that sense. The radio burst occurs a broad range of frequencies, which can vary substantially from one burst to the next (there are graphs of this in the paper linked above). But there's no sharp peak that can be accurately measured, as far as I know.

And even if there was, we don't understand the mechanism behind FRBs, so we wouldn't necessarily be able to distinguish a Doppler shift from some other effect that caused the frequency to change.

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#38

Post by krapp »

teraflop wrote: post #33
savrajsingh wrote: post #9

They didn’t mention a simpler solution: random emitter orbits behind something / Is occluded for the silent period?

I'm having a hard time imagining what kind of geometry would cause an orbiting object to be occluded for more than 50% of its orbital period.

Obviously the weird, non-euclidean geometry of some vast and incomprehensible machine built by eldritch abominations. When the stars have properly aligned, we will understand its true purpose all to well.

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#39

Post by dreamcompiler »

perlgeek wrote: post #6

Since it hasn't come up yet: whenever a new astronomical phenomenon is detected, people think "Aliens!" as the reason. In fact, when the first pulsar was discovered, it was (somewhat jokingly) called LGM-1 for "little green men". I'm sure the news hype cycle will come up with similar ideas this time, and I'm just as sure that we'll find a perfectly reasonable explanation not involving intelligent, extraterrestrial li…

There was a time when people thought a ball of fire moving across the sky every day must be alive. The universe is full of strange phenomena perfectly explainable by physics. This is no different.

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#40

Post by vmladenov »

EamonnMR wrote: post #30
JackFr wrote: post #7

> For the most part, these detections were one-offs, flashing briefly before disappearing entirely. I realize there is most likely an explanation that doesn’t require intelligent alien life, but that screams Dark Forest Theory.

We should broadcast the coordinates of a distant star to see what happens.

There are a lot of cool concepts in those books, but the sophon faster-than-light communication that props up a lot of the story was a bit too much for me.
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