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
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Is the Universe a Holographic Projection?

Luke and Obi-Wan look at a 3D hologram of Leia projected by R2D2 (Star Wars)
Luke and Obi-Wan look at a 3D hologram of Leia projected by R2D2 (Star Wars)

Could our cosmos be a projection from the edge of the observable Universe?

Sounds like a silly question, but scientists are seriously taking on this idea. As it happens, a gravitational wave detector in Germany is turning up null results on the gravitational wave detection front (no surprises there), but it may have discovered something even more fundamental than a ripple in space-time. The spurious noise being detected at the GEO600 experiment has foxed physicists for some time. However, a particle physicist from the accelerator facility Fermilab has stepped in with his suspicion that the GEO600 “noise” may not be just annoying static, it might be the quantum structure of space-time itself
Continue reading “Is the Universe a Holographic Projection?”

Introducing the Multiple Kill Vehicle (a.k.a. The Scariest Thing I’ve Seen All Day)

The MKV in an unnervingly steady hover (MDA)
The MKV in an unnervingly steady hover (MDA)

The ominously named Multiple Kill Vehicle (MKV) is the next advanced robotic weapon that could be deployed in space to defend against multiple incoming missiles. Designed and built by the US Missile Defence Agency, this little hovering craft will carry multiple anti-missile warheads to see off several threats.

To be honest, I didn’t write this post for the sake of showing off this robotic military tool, I actually think this is an interesting development for small, autonomous spacecraft. Also, when I watched the video of the test flight of the MKV, I had a wave of fear come over me. It may be small, but I sure wouldn’t like to bump into it during a dark orbit
Continue reading “Introducing the Multiple Kill Vehicle (a.k.a. The Scariest Thing I’ve Seen All Day)”

Pinhole Camera Solargraphy

The Clifton Suspension Bridge, Bristol, a single 6-month exposure solargraph (© Justin Quinnell)
The Clifton Suspension Bridge, Bristol, a single 6-month exposure solargraph (© Justin Quinnell)

Armed with the most basic photography device and plenty of time, Justin Quinnell has captured some of the most unique and entrancing views of the Sun over my hometown of Bristol. When I first saw this image, the iconic Clifton Suspension Bridge instantly jumped out at me. It took me a while to figure out what was going on, but after getting engrossed in Justin’s website all about pinhole photography, I soon realised this was a six-month exposure, capturing the Sun’s motion from winter solstice (December 21st, 2007) to summer solstice (June 19th, 2008)…
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High Resolution Earth Rise Video by Kaguya (SELENE)

A little bit of beautiful - the Earth rises over the lunar horizon (JAXA)
A little bit of beautiful - the Earth rises over the lunar horizon (JAXA)

Using its High Definition Television (HDTV) camera, the Japanese lunar probe Kaguya captured an astounding video of the Earth slowly rising above the lunar horizon. The video was actually released at the start of this month, but it has only just come to my attention. The video was recorded on September 30th, as the probe orbited 100 km above the Moon. Stunning.

See the tele-view “Full-Earth Rise” »

See the wide-angle Earth-set »

Read more about “Full-Earth Rise” »

Astroengine.com Selected for “Top 10 Space Blogs”

Astroengine in the Top 10!
W00t!

A huge thank you goes to Dave Mosher at the excellent blog Space Disco for adding Astroengine.com to the Blogs.com “Top 10 Space Blogs”! Not only did my site make it into the top 10, by sheer alphabetical luck, Astroengine is also right at the top. Awesome! I’ll wear my badge with pride.

Dave, I owe you a pint some time!

Cheers, Ian

GOCE is Suffering Major Delays, But Should be Dominating Space by February

No, it isn't sci-fi. It's the Porche of orbital engineering (GOCE/ESA)
No, it isn't sci-fi. It's the Porche of orbital engineering (GOCE/ESA)

The European Space Agency’s Gravity field and state-steady Ocean Circulation Explorer (GOCE) should be in space by now. In fact it should have been launched back on September 10th, but it wasn’t to be. After the spacecraft (which has a striking resemblance to something a little more sci-fi… like a star destroyer) had been sealed into the payload bay of the Rockot launch vehicle at Plesetsk cosmodrome 800 km from Moscow, I assumed that was it, we wouldn’t be seeing GOCE ever again. But there was a glitch in the guidance and navigation subsystem of the Breeze KM third stage, thus postponing GOCE’s big day. GOCE was cracked open from its rocket powered cocoon to await a Rockot oil change.

Now it seems the delays are mounting up for this amazing experiment and a launch doesn’t seem possible until February at the earliest…
Continue reading “GOCE is Suffering Major Delays, But Should be Dominating Space by February”

Saturn’s Hexagonal North Pole: What is Causing It?

Infrared observations of the south pole of Saturn as taken by the Cassini mission in 2007 and 2008 (NASA)
Infrared observations of the south pole of Saturn as taken by the Cassini mission in 2007 and 2008 (NASA)

The mystery of Saturn’s hexagonal shape embedded in its violent north polar cyclone just became more intriguing.

NASA’s Cassini probe has been orbiting the ringed gas giant for four years and has just returned some of the most detailed images of the planet’s stormy atmosphere to date. The south pole has been mapped and the north polar region has been imaged in near-infrared wavelengths. The north pole is currently facing away from the Sun, so by observing the atmosphere in these wavelengths, Cassini scientists can see Saturn’s cloud formations silhouette against the background glow of the gas giant’s internal heat. This provides the perfect opportunity to see the hexagon in unprecedented detail.

So what is generating this mysterious six-sided shape?
Continue reading “Saturn’s Hexagonal North Pole: What is Causing It?”

Enigmatic Magnetar Blasts to Life Inside Our Galaxy

An artist impression of one of the most intensely magnetic phenomena in our known Universe, the magnetar (ESO/L. Calcada)
An artist impression of one of the most intensely magnetic phenomena in our known Universe, the magnetar (ESO/L. Calcada)

It was identified as a gamma-ray burst, resulting from a massive explosion in a distant, young galaxy. Then astronomers realised that this flaring object was much closer to home, in fact it was a gamma-ray source within the Milky Way. Astronomers detected 40 visible-light flashes, only for the source to vanish as quickly as it mysteriously appeared. So what generated this huge firework display for astronomers to originally mistaken it for a gamma-ray burst?

It seems we have an answer, and it has surprised many.

One of the rarest objects ever observed may have sprung to life in our galaxy after a long period of calm. This object is a young neutron star with a magnetic field a billion billion times stronger than the Earth’s, otherwise known as a magnetar
Continue reading “Enigmatic Magnetar Blasts to Life Inside Our Galaxy”

“Apologies for calling it the Hay-dron Collider the other night, pure ignorance.”

Did he REALLY just say that? Brian Cox's expression says it all... (still from the BBC's Newsnight program)
You did NOT just say that! Brian Cox's expression says it all... (still from the BBC's Newsnight program)

It’s days like this that I worry for the future of science in the UK…

Sure, Sir David King is the former Chief Scientific Advisor for the UK government, but the opinions he voiced on last week’s BBC Newsnight airing caught my breath. If his short-sighted and ill informed ideas are indicative of the UK government’s science funding strategy, I’d suggest all UK-funded particle physicists pack up and move to Europe or the US.

In the aftermath of the LHC grand event on Wednesday, outspoken Newsnight host Jeremy Paxman was joined by King and the ever impressive Professor Brian Cox. The topic focused on how the Large Hadron Collider (LHC) will benefit mankind. As the media had been buzzing about the event for weeks, it was great to see a leading news opinion program set aside six minutes for a particle physics debate.

And what a debate it was! Let’s put it this way, Brian Cox got pretty irritated by King’s point that “brilliant people” should be attracted into other challenges to mankind, rather than focusing their attention on “navel searching” projects like the LHC. Brian’s response was awesome
Continue reading ““Apologies for calling it the Hay-dron Collider the other night, pure ignorance.””