It could be an alien fooling around with a pulsar to send a message. Just if that was the case, perhaps it would make more sense to send more easily decoded messages.
If the interval followed a sequence of prime numbers, factorials, or exponentials, this could be the only explanation and every astronomer would lose their mind, even more because it's 15K light years away, so there's no way to send a probe to it. As of now, the signal is ambiguous enough to let them keep their minds unblown.
My proposal: A sun with a large, dense asteroid belt orbiting it. The bursts we see are when there is a gap in the asteroids.
Something caused the asteroids to cluster into groups (maybe a shepherd planet with a resonance), so there are gaps 20 orbital minutes apart - this also explains the semi random nature of the signal.
To block the signal so completely the sun has to be small, and the asteroids large - or orbiting far away (but a far orbit means there are far more of them, making this theory less likely).
The signal has been detected since at least 1988. An asteroid belt around a sun would be dynamic and continuously changing, making it unlikely for the same 20-minute repeating pattern to persist for decades.
The bursts vary in intensity and duration, and occasionally don't happen at all within a given window. This is not consistent with a simple periodicity expected from gaps in an asteroid belt.
The repetition period of 22 minutes is very slow for an asteroid belt around a sun. Typical asteroid belts have orbital periods measured in hours to days, not minutes.
For asteroids to completely block the emission from the sun during each 20-minute gap would require an extremely large number of asteroids, far more than seen in our own solar system's asteroid belt.
The semi-randomness of the signal is difficult to explain by gaps in an asteroid belt, which would be expected to produce much more regular periodicity.
The required size and stability of such an asteroid belt, persisting for decades around a sun, is not consistent with current astrophysical models of asteroid belt dynamics.
Here are some other theories that could potentially explain GPM J1839–10:
Precessing black hole - The repeating radio bursts could be caused by a precessing black hole accreting material. The precession period of around 22 minutes could explain the observed repeating pattern. However, such slow precession is not well understood for black holes.
Colliding neutron stars - GPM J1839–10 could be two neutron stars in a binary system that collide every 22 minutes, producing the radio bursts. However, the persistence of the signal for decades is difficult to explain in this scenario.
Magnetar with fluctuating magnetosphere - A magnetar, a type of neutron star with an extremely powerful magnetic field, could have a magnetosphere that fluctuates on a timescale of around 22 minutes. This could cause repeated emitting and blocking of radio waves, producing the observed pattern. However, current magnetar models do not predict such slow fluctuations.
Interacting binary system - GPM J1839–10 could be two orbiting objects that interact every 22 minutes, disrupting material and producing the radio emission. Possibilities include a neutron star and black hole or two neutron stars. However, the required orbital period of around 22 minutes is extremely wide for a compact binary system.
Strange state of quantum chromodynamics - Some theorists have proposed exotic states of matter governed by quantum chromodynamics that could provide a source of persistent but fluctuating radio emission. However, such proposals are highly speculative at this point.
> The bursts vary in intensity and duration, and occasionally don't happen at all within a given window. This is not consistent with a simple periodicity expected from gaps in an asteroid belt.
Maybe we could obtain something like this with more than one object orbiting around, like on a ring. With enough objects in motion the blocking pattern can be obscured enough until a higher number of repetitions happens
I wonder how plausible it is that we just misunderstand the mechanisms driving pulsars and that it's just a plain old pulsar which just happens to be this slow due to some very rare interaction having slowed it down.
From my armchair I like the binary system theory best. One of the objects starts emitting when they approach each other. And occasionally the shining one is shadowed behind the other so we don't see the burst. Would require one object to be much bigger though, so it could hide the other for half a minute out of 22 minutes, and this seems impossible to me.
I wonder if it's possible to look at this closer. By closer I mean something like the technology that was used to get that black hole pic at recognizable resolution.
My understanding is probably not. The Event Horizon Telescope (EHT) used to image the supermassive black holes has an aperture the size of the Earth. The objects they imaged are close and massive. And even then, they had to do funny sophisticated image resolving to get an image.
https://eventhorizontelescope.org/
"The Event Horizon Telescope is an international collaboration capturing images of black holes using a virtual Earth-sized telescope"
Eventually, probably; I hope in our lifetime we'll get solar system sized observatories from sattelite networks, like a few dozen James Webbs flying around and focusing on a single point, that kinda thing.
It would have to be unblocking it, and not entirely regularly:
> Follow-on observations showed that the object repeated pretty regularly, with a periodicity of about 1,320 seconds (more commonly known as 22 minutes). There's a window of about 400 seconds centered on that periodicity, and a burst can appear anywhere within the window and will last anywhere from 30 to 300 seconds.
Ok. Then we have like "a sort of brownian movement" here, it seems... like a regular event being slightly modified later by a non regular event happening in the same interval of time.
Lets assume that the probability of a random event happening is 100% when we have a time interval wide enough, and that this interval is lower than 22 minutes. Too quick for most big space acts so it must be a minor event.
Lets assume also that random event needs to "reset" somehow, before to be able to repeat again, so we have some time where the emission of radio waves, the main event is always blocked.
Something like a sun eruption, or so...
Could be those magnetic waves be behind a second object that acts like a plasma? (Like just touching a sun crown very far away from the source, and being cancelled at intervals by the effect of plasma frequency and wave frequency interacting?.
Might it be caused by something as mundane as an inclined axis wrt Earth/Sol? IIRC some celestial bodies do not radiate uniformly in all directions, but only from the poles. If its normal rotation would keep the beams away from us, but there is a slight wobble in its inclination, that would mean that both the burst frequency and the wobble frequency could be faster than 1/22 minutes, and we're seeing only the product of those periods from here.
Huh, somehow I glossed over the part where a regular neutron star would have bursts from <1s to 60s, while this body has bursts between 30 and 300 seconds. So it's still a different phenomenon than known pulsars.
But I don't think it covers the core of what I meant to suggest/ask: if the object is spinning around 2 axes (for whatever reason) rather than one, that could still be an explanation why the observed periodicity from Earth does not match what we expect its actual rotation period to be.
They say a magnetar is ruled out because there were no x-rays, but I wonder if it is possible that there is something between it and us that blocks x-rays but passes lower energy photons?
Some kind of novel accretion mechanism dripping onto a compact object?
Since this is HN I'll throw out the idea that it is the breakup and destruction of a Dyson Sphere with material chaotically dripping semi periodically into the primary.
53 comments
[ 3.6 ms ] story [ 131 ms ] threadSomething caused the asteroids to cluster into groups (maybe a shepherd planet with a resonance), so there are gaps 20 orbital minutes apart - this also explains the semi random nature of the signal.
To block the signal so completely the sun has to be small, and the asteroids large - or orbiting far away (but a far orbit means there are far more of them, making this theory less likely).
Another "failed sun" that emits radio waves: https://www.space.com/brown-dwarf-star-radio-waves so maybe something like that.
Which behaves differently to this one
https://www.nasa.gov/feature/jpl/mysterious-dimming-of-tabby...
https://www.nzherald.co.nz/world/tabbys-star-may-not-be-alon...
https://en.wikipedia.org/wiki/Tabby%27s_Star
The signal has been detected since at least 1988. An asteroid belt around a sun would be dynamic and continuously changing, making it unlikely for the same 20-minute repeating pattern to persist for decades.
The bursts vary in intensity and duration, and occasionally don't happen at all within a given window. This is not consistent with a simple periodicity expected from gaps in an asteroid belt.
The repetition period of 22 minutes is very slow for an asteroid belt around a sun. Typical asteroid belts have orbital periods measured in hours to days, not minutes.
For asteroids to completely block the emission from the sun during each 20-minute gap would require an extremely large number of asteroids, far more than seen in our own solar system's asteroid belt.
The semi-randomness of the signal is difficult to explain by gaps in an asteroid belt, which would be expected to produce much more regular periodicity.
The required size and stability of such an asteroid belt, persisting for decades around a sun, is not consistent with current astrophysical models of asteroid belt dynamics.
Here are some other theories that could potentially explain GPM J1839–10:
Precessing black hole - The repeating radio bursts could be caused by a precessing black hole accreting material. The precession period of around 22 minutes could explain the observed repeating pattern. However, such slow precession is not well understood for black holes.
Colliding neutron stars - GPM J1839–10 could be two neutron stars in a binary system that collide every 22 minutes, producing the radio bursts. However, the persistence of the signal for decades is difficult to explain in this scenario.
Magnetar with fluctuating magnetosphere - A magnetar, a type of neutron star with an extremely powerful magnetic field, could have a magnetosphere that fluctuates on a timescale of around 22 minutes. This could cause repeated emitting and blocking of radio waves, producing the observed pattern. However, current magnetar models do not predict such slow fluctuations.
Interacting binary system - GPM J1839–10 could be two orbiting objects that interact every 22 minutes, disrupting material and producing the radio emission. Possibilities include a neutron star and black hole or two neutron stars. However, the required orbital period of around 22 minutes is extremely wide for a compact binary system.
Strange state of quantum chromodynamics - Some theorists have proposed exotic states of matter governed by quantum chromodynamics that could provide a source of persistent but fluctuating radio emission. However, such proposals are highly speculative at this point.
Maybe we could obtain something like this with more than one object orbiting around, like on a ring. With enough objects in motion the blocking pattern can be obscured enough until a higher number of repetitions happens
lol
Ah Outer Wilds is such a beautiful game, I'd highly recommend it to anyone who hasn't tried it.
(Hum... Something has been lighting up since 1988 and something is orbiting fast around it blocking the light each 20 minutes?)
> Follow-on observations showed that the object repeated pretty regularly, with a periodicity of about 1,320 seconds (more commonly known as 22 minutes). There's a window of about 400 seconds centered on that periodicity, and a burst can appear anywhere within the window and will last anywhere from 30 to 300 seconds.
Lets assume that the probability of a random event happening is 100% when we have a time interval wide enough, and that this interval is lower than 22 minutes. Too quick for most big space acts so it must be a minor event.
Lets assume also that random event needs to "reset" somehow, before to be able to repeat again, so we have some time where the emission of radio waves, the main event is always blocked.
Something like a sun eruption, or so...
Could be those magnetic waves be behind a second object that acts like a plasma? (Like just touching a sun crown very far away from the source, and being cancelled at intervals by the effect of plasma frequency and wave frequency interacting?.
So if your hypothesis is correct the objects orbiting must be distributed to cover more than 3/4 of the orbit.
all you need to know https://en.wikipedia.org/wiki/GPM_J1839%E2%88%9210
I did not learn anything new from the Wikipedia article, and the original article seems fine.
https://www.youtube.com/watch?v=0vKliRMfdTw
https://theconversation.com/a-mysterious-interstellar-radio-...
Stellar taxonomy and ecology is so interesting.
And while pulsar is a cool name, I think we missed our chance to name them whobblars.
I'm curious about a binary system though. Could it, through tidal locking have the stability to produce the longer duration signal?
But I don't think it covers the core of what I meant to suggest/ask: if the object is spinning around 2 axes (for whatever reason) rather than one, that could still be an explanation why the observed periodicity from Earth does not match what we expect its actual rotation period to be.
Since this is HN I'll throw out the idea that it is the breakup and destruction of a Dyson Sphere with material chaotically dripping semi periodically into the primary.