Strange radio signal from Proxima Centauri

[DavidCummings]

TL;DR Summary

Interested in opinions regarding the radio signal from Proxima Centauri.

https://www.scientificamerican.com/...66Wbqql-hoo91hA1WnCl9Azwqa84ly-zS6cjBiDFzlK8o

Excerpt:

Most curiously, it occupies a very narrow band of the radio spectrum: 982 megahertz, specifically, which is a region typically bereft of transmissions from human-made satellites and spacecraft . “We don’t know of any natural way to compress electromagnetic energy into a single bin in frequency” such as this one, Siemion says. Perhaps, he says, some as-yet-unknown exotic quirk of plasma physics could be a natural explanation for the tantalizingly concentrated radio waves. But “for the moment, the only source that we know of is technological.”

 

[StandardsGuy]

They didn't give the bandwidth. That would be an interesting fact. But it has no modulation and it drifts. Those facts don't suggest ETI, so it's most likely natural. It sounds like they have almost ruled out Earth sources. If they do, it is something that will teach us something with enough study.

 

[Jarvis323]

Does anyone know if the data available to download somewhere?

 

[DavidCummings]

They didn't give the bandwidth. That would be an interesting fact. But it has no modulation and it drifts. Those facts don't suggest ETI, so it's most likely natural. It sounds like they have almost ruled out Earth sources. If they do, it is something that will teach us something with enough study.

Thanks for bringing up the points about modulation and drift. That's interesting.

 

[Buzz Bloom]

it has no modulation and it drifts.

Are the drifts regular or irregular? If regular, it could be related to planet orbital effects.

 

[StandardsGuy]

Unknown. I take it the signal has not been re-observed.

https://www.msn.com/en-us/news/technology/alien-hunters-detect-mysterious-radio-signal-from-nearby-star/ar-BB1c3rJU

 

[SpaceJacob]

Until scientists proved that there is civilization in Alpha Centauri, these signals mean nothing. However, I don't deny the possibility of reaching this star system in the far future. I heard that uncrewed mission to Alpha Centauri for 2069. Btw, I think many new space agencies and aerospace companies will become leaders by that time. I have high hopes for a British rocket manufacturing company; I'm sure that someone here has probably heard about it. They also use innovative technologies; therefore, I think it would be a good decision for all leading space agencies to work together and achieve better results. Who knows, perhaps, Alpha Centauri is closer than it seems.

 

[stefan r]

Until scientists proved that there is civilization in Alpha Centauri, these signals mean nothing. ...

It is a unique data point that has never been observed before. Hard to get more significant and meaningful in astronomy.

 

[sophiecentaur]

Hard to get more significant and meaningful in astronomy.

I'd have to argue with that. For significance, you need corroboration / repeatability and a one-off doesn't have that. It's worth pointing out that only the direction of the source can be measured and if the observation is brief, there is no clue about the actual distance. Moreover, the directivity of RF receiving antenna is usually pretty poor so the signal definitely came from 'somewhere in that sort of direction' .

 

[Vanadium 50]

This so-called result has not been published, so we're just talking about rumor. Although @sophiecentaur , the angular resolution of radio telescopes might be better than you think. It's about an arcsecond for the best arrays - better than your eyeball.

 

[sophiecentaur]

the angular resolution of radio telescopes might be better than you think. It's about an arcsecond for the best arrays - better than your eyeball.

I wasn't sure about the numbers involved but, looking at Hubble and other images, I can see many more than just one star in a radius of 1 arc second. Whilst the most obvious candidate would be the brightest (and often the nearest), visually, that's not a clincher.

 

[Vanadium 50]

Again, it might be better than you think. We don't know what measurements were made or when they were made (because we don't have a paper - just rumors), but Proxima Centauri is moving against the background stars at an arcsecond every few months.

 

[sophiecentaur]

Again, it might be better than you think. We don't know what measurements were made or when they were made (because we don't have a paper - just rumors), but Proxima Centauri is moving against the background stars at an arcsecond every few months.

Bah! Too danged clever for their own good, these Astronomers. They are champions of lateral thinking and can get all sorts of information out of what they see. Proper motion, then...

How long was the source detected for?

 

[Vanadium 50]

How long was the source detected for?

We don't know. No paper. Just rumors.

And while most motion is proper motion, parallax is not hugely smaller.

 

[stefan r]

How long was the source detected for?

From astronomy.com:

Although the press reports are a bit unclear on exactly how and when Parkes detected the signal, it apparently showed up during five 30-minute periods over several days, all while the telescope was pointing directly at Proxima. Notably, when the telescope was turned away from the star, the signal vanished. Ultimately, the signal’s origin appears tightly constrained within a 16'-wide circle — roughly half the size of the Full Moon — around Proxima Centauri on the sky.

I'd have to argue with that. For significance, you need corroboration / repeatability and a one-off doesn't have that. It's worth pointing out that only the direction of the source can be measured and if the observation is brief, there is no clue about the actual distance. Moreover, the directivity of RF receiving antenna is usually pretty poor so the signal definitely came from 'somewhere in that sort of direction' .

All data points need to be corroborated and repeated. But all repeated measurements had to be measured once before they could be repeated.

The signal originating from a planet orbiting Proxima Centauri is among the most mundane options. A radio signal originating in our own Oort cloud would be a big deal. Would be the first directly detected object in the Oort cloud. A signal originating from the Carina-Sagittarius arm would need to be a huge transmitter. If transmitters are "lurking about" near the Great Emu we really need to figure out what they are, why they are lurking, and which way are they moving. Any distance (except inside Earth orbit) is interesting and should be observed more closely.