Repeating “Fast Radio Bursts” Detected in Another Galaxy — Probably Not Aliens, Interesting Anyway

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The Green Bank Radio Telescope (NRAO)

A radio astronomy project intended to find signals from intelligent aliens has announced the intriguing detections of “repeating” fast radio bursts (FRBs) from a single source in a galaxy three billion light-years distant. This is definitely an exciting development, but probably not for the reasons you think.

The ambitious $100 million Breakthrough Listen project aims to scan a million stars in our galaxy and dozens of nearby galaxies across radio frequencies and visible light in hopes of discovering a bona fide artificial signal that could be attributed to an advanced alien civilization. But in its quest, Breakthrough Listen has studied the signals emanating from FRB 121102 — and recorded 15 bursts — to better understand what might be causing it.

FRBs remain a mystery. First detected by the Parkes Radio Telescope in Australia, these very brief bursts of radio emissions seemed to erupt from random locations in the sky. But the same location never produced another FRB, making these bizarre events very difficult to understand and impossible to track.

Hypotheses ranged from powerful bursts of energy from supernovae to active galactic nuclei to (you guessed it) aliens, but until FRB 121102 repeated itself in 2015, several of these hypotheses could be ruled out. Supernovae, after all, only have to happen once — this FRB source is repeating, possibly hinting at a periodic energetic phenomenon we don’t yet understand. Also, because FRB 121102 is a repeater, in 2016 astronomers could trace back the location of its source to a dwarf galaxy 3 billion light-years from Earth.

Now we ponder the question: What in the universe generates powerful short bursts of radio emissions from inside a dwarf galaxy, repeatedly?

Using the Green Bank Telescope in the West Virginia, scientists of Breakthrough Listen recorded 400 TB of data over a five hour period on Aug. 26. In these data, 15 FRBs were recorded across the 4 to 8 GHz radio frequency band. The researchers noted the characteristic frequency dispersion of these FRBs, caused by the signal traveling through gas between us and the source.

Now that we have dedicated and extremely detailed measurements of this set of FRBs, astrophysicists can get to work trying to understand what natural phenomenon is generating these bursts. This is the story so far, but as we’re talking radio emissions, mysteries and a SETI project, aliens are never far away…

Probably Not Aliens

It may be exciting to talk about the possibility of aliens generating this signal — as a means of communication or, possibly, transportation via beamed energy — but that avenue of speculation is just that: speculation. But to speculate is understandable. FRBs are very mysterious and, so far, astrophysicists don’t have a solid answer.

But this mystery isn’t without precedent.

In 1967, astronomers Jocelyn Bell Burnell and Antony Hewish detected strange radio pulses emanating from a point in the sky during a quasar survey to study interplanetary scintillation (IPS). The mysterious pulses had an unnaturally precise period of 1.33 seconds. At the time, nothing like it had been recorded and the researchers were having a hard time explaining the observations. But in the back of their minds, they speculated that, however unlikely, the signal might be produced by an alien intelligence.

During a dinner speech in 1977, Bell Burnell recalled the conundrum they faced:

“We did not really believe that we had picked up signals from another civilization, but obviously the idea had crossed our minds and we had no proof that it was an entirely natural radio emission. It is an interesting problem – if one thinks one may have detected life elsewhere in the universe how does one announce the results responsibly? Who does one tell first? We did not solve the problem that afternoon, and I went home that evening very cross here was I trying to get a Ph.D. out of a new technique, and some silly lot of little green men had to choose my aerial and my frequency to communicate with us.”

This first source was nicknamed “LGM-1” (as in “Little Green Men-1”), but far from being an artificial source, the duo had actually identified the first pulsar — a rapidly-spinning, highly magnetized neutron star that generates powerful emissions from its precessing magnetic poles as it rotates.

This is how science works: An interesting signal is detected and theories are formulated as to how that signal could have been generated.

In the case of LGM-1, it was caused by an as-yet-to-be understood phenomenon involving a rapidly-spinning stellar corpse. In the case of FRB 121102, it is most likely an equally as compelling phenomenon, only vastly more powerful.

The least likely explanation of FRB 121102 makes a LOT of assumptions, namely: aliens that have become so incredibly technologically advanced (think type II or even type III on the Kardashev Scale) that they can fire a (presumably) narrow beam directly at us through intergalactic space over and over again (to explain the repeated FRB detections) — the odds of which would be vanishingly low — unless the signal is omnidirectional, so they’d need to access way more energy to make this happen. Another assumption could be that intelligent, technologically advanced civilizations are common, so it was only a matter of time before we saw a signal like FRB 121102.

Or it could be a supermassive black hole (say) doing something very energetic that science can’t yet explain.

Occam’s razor suggests the latter might be more reasonable.

This isn’t to say aliens don’t exist or that intelligent aliens aren’t transmitting radio signals, it just means the real cause of this particular FRB repeater is being generated by a known phenomenon doing something unexpected, or a new (and potentially more exciting) phenomenon that’s doing something exotic and new. It doesn’t always have to be aliens.

h/t:

Alien vs. Comet: Is the SETI “Wow!” Signal Dead? (Astroengine Video)

There’s a new hypothesis about what happened on August 15, 1977, and, sadly, it doesn’t involve aliens — just a photobombing comet. I was surprised about the controversy surrounding Antonio Paris’ research into the possibility of comets generating radio signals at 1420MHz and mimicking the famous “Wow!” signal nearly 40 years ago, so I decided to record Astroengine’s second YouTube video on the topic. Enjoy! And remember to subscribe and like, there’s a lot more to come!

SETI “Wow!” Signal Wasn’t Chatty Aliens After All — It Was a Fizzing Comet

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Big Ear Radio Observatory

On Aug. 15, 1977 at 10:16 p.m. ET Ohio State University’s Big Ear radio telescope detected a curious signal from deep space. Nearly 40 years later, we finally know what caused it and, sadly, it’s not aliens.

For decades, the signal has been the strongest piece of “go-to” evidence that intelligent extraterrestrials are out there in our galaxy. When found by astronomer Jerry Ehman on that fateful night, the 72-second signal — that had been recorded on a computer printout — certainly stood out.

While pointing at three star systems called Chi Sagittarii in the constellation of Sagittarius, Big Ear had picked up a powerful burst of radio waves. To the untrained eye, the assortment of printed digits might not mean much, but as I wrote in 2016, those letters and numbers could hold the answer to the biggest question we’re currently asking of the universe: Are we alone?

The Big Ear printout contains a bunch of apparently random numbers and letters, but Ehman’s red pen circles a cluster of digits “6EQUJ5” with other circles around a “6” and “7” on separate columns. This particular code first uses the numbers 1-9 and then the alphabet A-Z to denote signal strength. As the burst suggests, the signal strength hit “6” and then blasted through the letters reaching a peak of “U” before subsiding back into the numerical scale at “5.” There was then a slight wave trailing the main signal (hence the circled “6″ and “7″). The wave profile of the “Wow!” signal is graphically envisaged here. (Discovery News, April 18, 2016)

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Maksim Rossomakhin

The maddening thing about the Wow! signal has always been a lack of replication. To science, one random signal in the dark proves nothing. It would be like trying to plot a trend line on a graph with one data point. More data is obviously needed and yet, since 1977, there’s been no other radio signal quite like it.

Curious, yes. Definite proof of chatty aliens? A solid nope.

So, when researching other possible causes of the Wow! signal that were also rare occurrences (but not aliens), Antonio Paris of St Petersburg College, Fla. (and an ex-analyst of the US Department of Defense), suggested that the signal might have been generated by one of two comets that serendipitously drifted into the line of sight of the Big Ear radio telescope.

In 1977, neither 266P/Christensen and 335P/Gibbs were known of (they were discovered in 2006 and 2008 respectively) and Paris calculated that both comets would have been in the right place in the sky when the Wow! signal was recorded.

What’s more, the Wow! signal has a frequency of 1420MHz — the same frequency that neutral hydrogen radiates at. Hydrogen is abundant in our universe, so this frequency is commonly observed in astronomy.

At first blush, observing in this frequency to look for alien transmissions might seem like a fool’s errand; if the universe is humming in hydrogen noise, why would aliens bother using that frequency to ping their extraterrestrial neighbors?

Through SETI logic, the frequency of neutral hydrogen might be used by advanced civilizations as a kind of interstellar water cooler. It is the most abundant signal in the universe, every intelligent life-form would know this. So why not use 1420MHz as THE frequency to communicate across the light-years in hopes that other civilizations might already be tuned in?

But a SETI signal would need to stand out from the crowd — it would need to be powerful and possess other qualities that hint at its artificial nature. But should a comet quickly pass through the observing window of a radio telescope, Paris predicted that the received 1420MHz signal might mimic that of an artificial source.

And this year, an opportunity presented itself. Comet 266P/Christensen would pass through the sky in a similar orbital position as it did in 1977. During an observing campaign from November 2016 to February 2017, Paris studied the radio frequencies coming from the region and from the comet itself. He also compared these observations with other known comets.

The upshot: 266P is indeed producing a strong 1420MHz signal, as are other comets.

“The results of this investigation, therefore, conclude that cometary spectra are detectable at 1420 MHz and, more importantly, that the 1977 “Wow!” Signal was a natural phenomenon from a solar system body,” he writes in a study published in the Journal of the Washington Academy of Sciences

It appears that, in this case, the signal wasn’t aliens trying to make contact with us; it was a chance comet that just happened to be in the right place at the right time.

So, back to that alien megastructure

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Fox

What Do You See When SETI’s Allen Telescope Array Is Aimed At The Sun?

A comparison between an observation of the sun using the ATA's 2.75 GHz band (left) and SOHO's 195A filter. Both are near-simultaneous observations on Oct. 1, 2009 (Saint-Hilaire et al., 2011)
A comparison between an observation of the sun using the ATA's 2.75 GHz band (left) and SOHO's 195A filter. Both are near-simultaneous observations on Oct. 1, 2009 (Saint-Hilaire et al., 2011).

And no, “aliens” isn’t the answer.

The Allen Telescope Array (ATA), located near Hat Creek, California, isn’t only used by the SETI Institute to seek out signals from extraterrestrial civilizations. The 42 6.1-meter antennae form an interferometer that can be used for a variety of astronomical studies — in reality, this is the main focus of the project. SETI studies “piggyback” the active astronomical research, passively collecting data.

Due to the radio interferometer’s wide field of view, one surprising use of the ATA is solar astronomy — at radio frequencies. The ATA can be used to simultaneously observe the whole of the solar disk at a range of frequencies rarely studied. As outlined in a recent arXiv publication, a University of California, Berkeley, team of astronomers headed by Pascal Saint-Hilaire have carried out the first ATA solar study, producing images of the sun in a light we rarely see it in (shown above).

According to the paper, active regions were observed at radio and microwave frequencies, spotting the emissions associated with bremsstrahlung — electromagnetic radiation generated by accelerated charged particles caught in intense magnetic fields, a feature typical inside solar active regions. Also, coronal interactions, or gyroresonance, between solar plasma and plasma waves (propagating along magnetic field lines) was detected.

Combining the ATA’s wide field of view, range of frequencies and high resolution, it looks like the ATA is the only solar radiotelescope on the planet.

For more on this fascinating study, read “Allen Telescope Array Multi-Frequency Observations of the Sun,” Saint-Hilaire et al., 2011. arXiv:1111.4242v1 [astro-ph.SR]

Why Is SETI Not An Interstellar Switchboard?

Monolith by highdarktemplar on DeviantArt.
"Monolith" by highdarktemplar on DeviantArt.

On reading an article in The Daily Galaxy today, I was interested by what the author had to say. In a nutshell, the article pointed out that it is a big mistake to believe we are the only intelligent life in the Milky Way.

Why is that?

The only reason given was that there are billions of stars, it is therefore foolish to think we are the only example of an advanced species. Unfortunately, there is no evidence to suggest that we aren’t the only intelligent life form in our galaxy. Just because there are hundreds of billions of stars possibly with billions of habitable planets does not constitute evidence that we’re not alone. That’s what science is all about, formulating a theory and then gathering the evidence. Simply saying, “There’s lots of stars, therefore there must be an intelligent species out there,” doesn’t cut it.

Dr Frank Drake toiled with this idea to eventually arrive at the famous Drake Equation, a concept I have never felt at ease with:

At first glance, we could say that the Drake equation really is nonsense (after all, how can any equation predict more than one intelligent civilization in our galaxy, when we only have experience of one: us), and that we are the only kids on the Milky Way block. — from If There’s an Alien Race Living on our Doorstep, Why Can’t We Hear Them?

How can you arrive at the conclusion that we are not the only intelligent life in the galaxy simply because there are a lot of stars?

Familiarity

What can we expect ET to look like?
What can we expect ET to look like?

It is true that the Milky Way contains billions of stars, of which a high percentage probably have exoplanets not dissimilar to Earth orbiting them. There’s every chance that a smaller percentage of those Earth-like terrestrial exoplanets have some kind of basic life form slivering around (or indeed swimming, flying, walking or ‘talking’). Also, there’s the chance that some of these exoplanets have nurtured something that we’d consider to be ‘intelligent.’

Now this is where things start to get a bit tricky.

There are massive international efforts under way to find any kind of extraterrestrial life. We’re toasting soil samples on Mars in the hope of finding the biological signature, and we’re using full-blown antennae scouring the skies for any organized signal from an intelligent alien species. However, whether we are looking for microbial life in the Solar System or something a little more sophisticated beyond, our search for extraterrestrial life is based on only one model: Earth.

It’s all very well saying that we should be looking for other possible forms of life, but if we have no experience of it, how do we know what to look for?

It’s a similar question to, “What is beyond a black hole’s event horizon?” We have no idea, because we cannot experience it, the physics of our Universe simply do not apply beyond an event horizon.

There are a lot of ideas, theories and conjecture but at the end of the day, we have to assume ET will have some trait we are familiar with.

When looking for intelligent extraterrestrials we make the assumption that these civilizations have progressed in a similar way to us, eventually transmitting radio signals (perhaps even laser beacons) to communicate on their home world, between planets with their own kind, or even reaching out into the cosmos, signalling their presence to other life forms capable of receiving interstellar signals.

We’ve been leaking radio signals into space for the last century and we are constantly communicating with our planetary probes. There’s every chance that if there’s an intelligent alien (with a radio receiver) within 100 light years, we may have already been detected. We are also being a bit more proactive these days, using programs such as Messaging Extraterrestrial Intelligence (METI) to make our presence known. (But what should we be saying?)

SETI, METI, SETA… SETT?

The Arecibo radio antenna, used by SETI
The Arecibo radio antenna, used by SETI

Unfortunately, apart from one isolated case, the Search for Extraterrestrial Intelligence (SETI) has drawn up blanks, we don’t think we’ve heard anything in the cosmos that’s originated from an alien.

On this single null result, we could jump to the conclusion that there is no other form of ‘intelligent’ life in our galaxy. Say if the ‘Rare Earth‘ theory is correct, and we are indeed the only form of intelligent life in our galaxy? But there are other explanations. What if ET is signalling via another method? What if there is some interstellar mechanism that is hindering (or even blocking) the transmission of electromagnetic communications? All these questions are valid as there is no scientific evidence to support otherwise. It’s very quiet out there, a fact that is bugging scientists quite a bit, and this problem been dubbed the Fermi Paradox.

The Milky Way is very old, in fact, the oldest star in our galaxy has been burning for 13.2 billion years (compare that with the age of the Universe at 13.74 billion years); you’d logically think that something resembling an intelligent civilization would have popped into existence in that time. If they did, surely we’d have detected them by now, wouldn’t we?

Actually, this spawns yet another debate: Have ancient interstellar alien civilizations come and gone? Was there a frenzy of intelligent life popping up all over the galaxy in the billions of years that our Sun was a proto-star surrounded by a proto-planetary disk? If old alien intelligence has since become extinct, our few thousand years as an evolving civilization is a mere spark in universal time scales. Could it be that we’ll have to wait until we can actually visit interstellar destinations first-hand to do the SETI equivalent of an archaeological dig, looking for alien artefacts? Perhaps SETI should be changed to the Search for Extraterrestrial Artefacts (SETA), where we’d have to look for evidence of alien civilizations past.

Dyson Microcosm by justravelin on DeviantArt
"Dyson Microcosm" by justravelin on DeviantArt

There’s another factor to consider. What if an advanced extraterrestrial civilization simply isn’t transmitting? If this is the case, perhaps we should consider a Search for Extraterrestrial Technology (SETT). In this case we could look for alien megastructures, searching for the stuff of science fiction. These structures could include examples of Dyson Spheres, huge alien-made hollow spheres containing a star; a means to harvest all the stellar energy for a vastly advanced civilization.

These are all options, and we shouldn’t close any possibility, no matter how extreme they may be.

Conclusion

There’s a reason why we haven’t received a signal via SETI, but we have no idea about what it could be. We really could be alone in the Milky Way. But then again, there’s a huge number of reasons why we might not be receiving a message from an intelligent species.

SETI may not be an interstellar switchboard, but the reasons for this are far from obvious. The theory that we are alone is just as valid as the theory that we are actually a part of a vast interstellar ecosystem. Until we have scientific evidence, we can’t say either way.

Could Active-SETI Learn From… Twitter?

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The Search for Extraterrestrial Intelligence (SETI) has been an ongoing endeavour for the last 50 years. Detecting radio communications from an alien civilization would be the most profound event in mankind’s history; its effect would change the way we view our origin and our place in the Universe. It could mean that far from “being alone” we could be existing in a cosmic ecosystem, where life is more common than not and advanced extraterrestrial civilizations are no longer science fiction. A positive SETI signal would affect us globally; science, religion, society, daily life would alter radically.

Unfortunately, SETI is currently drawing up blanks. Apart from one or two inconclusive signs, it looks like we live in a dead part of the galaxy. Life As We Know It™ is an Earth-only affair. Who knows, we might be searching for another five decades and still be no closer to answering the question “are we alone?

Not to be too downhearted, scientists have been trying to make our presence felt by reversing SETI; we’ve been Messaging Extraterrestrial Intelligence (METI, a.k.a. “Active-SETI”) ever since we attached a plaque depicting the human form and a handy galactic map to Earth to the side of the Pioneer probes in the 1970s. Now we send a variety of radio signals to the stars in the hope of attracting ET’s attention.

But what signal do we send? Do we send a message with only good stuff from Earth? Or should we send a more gritty message, detailing our flaws as well as achievements? What actually makes a “good” METI signal in the first place?

Perhaps SETI could take some advice from the evolving social media scene, after all, when done right, there’s no more efficient way of conveying a clear message via 140 characters or less…
Continue reading “Could Active-SETI Learn From… Twitter?”

If There’s an Alien Race Living on our Doorstep, Why Can’t We Hear Them?

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An alien civilization could be transmitting, but we can't hear them (© Steve Swayne via Flickr)

As I was watching Battlestar Galactica last night, I was thinking about the lack of alien civilizations in the show. To be honest, I tire easily of humanoid alien beings with curiously shaped heads synonymous with Star Trek et al., so I’m loving the fact a far-off human colony created their own evil race, the Cylons. So far, so good, I’m getting sucked into BSG (will it be as good as, or even better than Bablyon 5? That has yet to be seen, but it looks promising).

These thoughts took me back to an Astroengine article I wrote in November with my usual gripe about our obsession for looking under rocks on Mars (The Search For Life, What’s the Point?). I reached the conclusion that I’d much rather be pottering around in an empty cosmos, devoid of life, than bumping into an angry neighbour who wants to probe/assimilate/hybridize me. Science fiction musings I know, but it isn’t that far from some of the conclusions that could arrive from using the famous Drake equation that underpins our incessant search for intelligent extraterrestrial life.

Today, I was referred to some research addressing the Fermi Paradox, although we haven’t heard from our extra-terrestrial neighbours yet, doesn’t mean they’re not transmitting. The galaxy could be teeming with intelligent aliens, but we just can’t hear them
Continue reading “If There’s an Alien Race Living on our Doorstep, Why Can’t We Hear Them?”

The Search For Life, What’s the Point?

Another mission, another brave “search for life”…

Is it me, or does virtually every robotic foray into space have some ET-searching component attached? In the case of Mars exploration, every lander and rover’s prime directive is find life, evidence of past life, potential for life or the building blocks of life. Even the very first man-made artefact to land (crash) on the planet, the 1971 Soviet Mars 2 mission, was designed to find organic compounds and… any sign of life.

On writing an article yesterday (“Wasteful” Sample Storage Box Removed from Mars Science Laboratory), I started to think that we might just be trying a little too hard and spending too much money on this endeavour. Perhaps there’s another way for us to work out if we are, indeed, an interplanetary (possibly intergalactic?) oasis, or a component of a biological cosmic zoo…
Continue reading “The Search For Life, What’s the Point?”