Updates on ‘Oumuamua. Maybe it’s a Comet, Actually. Oh, and no Word From Aliens.

On October 19th, 2017, the Panoramic Survey Telescope and Rapid Response System-1 (Pan-STARRS-1) in Hawaii announced the first-ever detection of an interstellar object, named 1I/2017 U1 (aka. ‘Oumuamua). After originally hypothesizing that it was a comet, observations performed by the European Southern Observatory (ESO) and other astronomers indicated that it was likely a strange-looking asteroid measuring about 400 meters (1312 ft) long.

Since that time, multiple surveys have been conducted to determine the true nature of this asteroid, which have included studies of its composition to Breakthrough Listen‘s proposal to listen to it for signs of radio transmissions. And according to the latest findings, it seems that ‘Oumuamua may actually be more icy than previously thought (thus indicated that it is a comet) and is not an alien spacecraft as some had hoped.

The first set of findings were presented in a study that was recently published in the scientific journal Nature, titled “Spectroscopy and thermal modelling of the first interstellar object 1I/2017 U1 ‘Oumuamua“. The study was led by Alan Fitzsimmons of Queen’s University Belfast, and included members from The Open University in Milton Keynes, the Institute for Astronomy (IfA) at the University of Hawaii, and the European Southern Observatory (ESO).

‘Oumuamua, as imaged by the William Herschel Telescope on October 29th, 2017. Credit: Queen’s University Belfast/William Herschel Telescope

As they indicate in their study, the team relied on information from the ESO’s Very Large Telescope in Chile and the William Herschel Telescope in La Palma. Using these instruments, they were able to obtain spectra from sunlight reflected off of ‘Oumuamua within 48 hours of the discovery. This revealed vital information about the composition of the object, and pointed towards it being icy rather than rocky. As Fitzsimmons explained in op-ed piece in The Conversation:

“Our data revealed its surface was red in visible light but appeared more neutral or grey in infra-red light. Previous laboratory experiments have shown this is the kind of reading you’d expect from a surface made of comet ices and dust that had been exposed to interstellar space for millions or billions of years. High-energy particles called cosmic rays dry out the surface by removing the ices. These particles also drive chemical reactions in the remaining material to form a crust of chemically organic (carbon-based) compounds.”

These findings not only addressed a long-standing question about ‘Oumuamua true nature, it also addresses the mystery of why the object did not experience outgassing as it neared our Sun. Typically, comets experience sublimation as they get closer to a star, which results in the formation of a gaseous envelope (aka. “halo”). The presence of an outer layer of carbon-rich material would explain why this didn’t happen ‘Oumuamua.

They further conclude that the red layer of material could be the result of its interstellar journey. As Fitzsommons explained, “another study using the Gemini North telescope in Hawaii showed its color is similar to some ‘trans-Neptunian objects’ orbiting in the outskirts of our solar system, whose surfaces may have been similarly transformed.” This red coloring is due to the presence of tholins, which form when organic molecules like methane are exposed to ultra-violet radiation.

Similarly, another enduring mystery about this object was resolved thanks to the recent efforts of Breakthrough Listen. As part of Breakthrough Initiatives’ attempts to explore the Universe and search for signs of Extra-Terrestrial Intelligence (ETI), this project recently conducted a survey of ‘Oumuamua to determine if there were any signs of radio communications coming from it.

While previous studies had all indicated that the object was natural in origin, this survey was more about validating the sophisticated instruments that Listen relies upon. The observation campaign began on Wednesday, December 13th, at 3:00 pm EST (12:00 PST) using the Robert C. Byrd Greenbank Radio Telescope, the world’s premiere single-dish radio telescope located in West Virginia.

The observations period was divided into four “epochs” (based on the object’s rotational period), the first of which ran from 3:45 pm to 9:45 pm ET (12:45 pm to 6:45 pm PST) on Dec 13th, and last for ten hours. During this time, the observation team monitored ‘Oumuamua across four radio bands, ranging from the 1 to 12 GHz bands. In addition to calibrating the instrument, the survey accumulated 90 terabytes of raw data over after observing ‘Oumuamua itself for two hours.

The initial results and data were released last week (Dec. 13th) and are available through the Breakthrough Listen archive. As Andrew Siemion – the Director of Berkeley SETI Research Center who took part in the survey – indicated in a Breakthrough Initiatives press release:

“It is great to see data pouring in from observations of this novel and interesting source. Our team is excited to see what additional observations and analyses will reveal”.

So far, no signals have been detected, but the analysis is far from complete. This is being conducted by Listen’s “turboSETI” pipeline, which combs the data for narrow bandwidth signals that are drifting in frequency. This consists of filtering out interference signals from human sources, then matching the rate at which signals drift relative to the expected drift caused by ‘Oumuamua’s own motion.

In so doing, the software attempts to identify any signals that might be coming from ‘Oumuamua itself. So far, data from the S-band receiver (frequencies ranging from 1.7 to 2.6 GHz) has been processed, and analysis of the remaining three bands – which corresponds to receivers L, X, and C is ongoing. But at the moment, the results seem to indicate that ‘Oumuamua is indeed a natural object – and an interstellar comet to boot.

This is certainly bad news for those who were hoping that ‘Oumuamua might be a massive cylinder-shaped generation ship or some alien space probe sent to communicate with the whales! I guess first contact – and hence, proof we are NOT alone in the Universe – is something we’ll have to wait a little longer for.

Further Reading: The Conversation, Nature, Breakthrough Initiatives

Weekly Space Hangout – Dec 13, 2017: Emilio Enriquez and SETI’s Breakthrough Listen Initiative

Hosts:
Fraser Cain (universetoday.com / @fcain)
Dr. Paul M. Sutter (pmsutter.com / @PaulMattSutter)
Dr. Kimberly Cartier (KimberlyCartier.org / @AstroKimCartier )
Dr. Morgan Rehnberg (MorganRehnberg.com / @MorganRehnberg ChartYourWorld.org)

Special Guests:
Dr. Emilio Enriquez is a Post Doc at the Berkeley SETI Research Center and a member of the Breakthrough Listen Initiative (http://seti.berkeley.edu/listen/). Emilio is the lead author of two recent SETI Research Center publications about Ross 128 b, the nearby exoplanet that researchers feel may have conditions that are conducive to life.

His expertise is in modelling of physical processes in galaxies, such as gas accretion onto galaxies, star formation, stellar feedback, gas accretion onto black holes, among other similar mechanisms. He also works with large multi-wavelength surveys of galaxies to study the connection between galaxies and their central super-massive black holes.

Announcements:

If you would like to join the Weekly Space Hangout Crew, visit their site here and sign up. They’re a great team who can help you join our online discussions!

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Breakthrough Listen is Going to Scan ‘Oumuamua, You Know, Just to be Sure it’s Just an Asteroid and Not a Spaceship.

On October 19th, 2017, the Panoramic Survey Telescope and Rapid Response System-1 (Pan-STARRS-1) in Hawaii announced the first-ever detection of an interstellar asteroid, named 1I/2017 U1 (aka. ‘Oumuamua). Based on subsequent measurements of its shape (highly elongated and thin), there was some speculation that it might actually be an interstellar spacecraft (the name “Rama” ring a bell?).

For this reason, there are those who would like to study this object before it heads back out into interstellar space. While groups like Project Lyra propose sending a mission to rendezvous with it, Breakthrough Initiatives (BI) also announced its plans to study the object using Breakthrough Listen. As part of its mission to search for extra-terrestrial communications, this project will use the Greenbank Radio Telescope to listen to ‘Oumuamua for signs of radio transmissions.

Observations of ‘Oumuamua’s orbit revealed that it made its closest pass to our Sun back in September of 2017, and has been on its way back to interstellar space ever since. When it was observed back in October, it was passing Earth at a distance of about 85 times the distance between Earth and the Moon, and was traveling at a peak velocity of about 315,430 km/h (196,000 mph).

This indicated that, unlike the many Near-Earth Objects (NEOs) that periodically cross Earth’s orbit, this asteroid was not gravitationally bound to the Sun. In November, astronomers using the ESO’s Very Large Telescope (VLT) at the Paranal Observatory in Chile were also able to determine the brightness and color of the asteroid, which allowed for precise calculations of its size and shape.

Basically, they determined that it was 400 meters (1312 ft) long and very narrow, indicating that it was shaped somewhat like a cigar. What’s more, the idea of a cigar or needle-shaped spacecraft is a time-honored concept when it comes to science fiction and space exploration. Such a ship would minimize friction and damage from interstellar gas and dust, and could rotate to provide artificial gravity.

For all of these reasons, it is understandable why some responded to news of this asteroid by making comparisons to a certain science fiction novel. That would be Arthur C. Clarke’s Rendezvous with Rama, a story of a cylindrical space ship that travels through the Solar System while on its way to another star. While a natural origin is the more likely scenario, there is no consensus on what the origin this object might be – other than the theory that it came from the direction of Vega.

Hence why Breakthrough Listen intends to explore ‘Oumuamua to determine whether it is truly an asteroid or an artifact. Established in January of 2016, Listen is the largest scientific research program aimed at finding evidence of extra-terrestrial intelligence with established SETI methods. These include using radio observatories to survey 1,000,000 of the closest stars (and 100 of the closest galaxies) to Earth over the course of ten years.

Breakthrough Listen will monitor the 1 million closest stars to Earth over a ten year period. Credit: Breakthrough Initiatives

Listen’s observation campaign will begin on Wednesday, December 13th, at 3:00 pm EST (12:00 PST), using the Greenbank Radio Telescope. This 100-meter telescope is the world’s premiere single-dish radio telescope and is capable of operating at millimeter and submillimeter wavelengths. It is also the mainstay of the NSF-funded Green Bank Observatory, located in West Virginia.

The first phase of observations will last a total of 10 hours, ranging from the 1 to 12 GHz bands, and will broken down into four “epochs” (based on the object’s rotational period). At present, ‘Oumuamua is about 2 astronomical units (AUs) – or 299,200,000 km; 185,900,000 mi – away from Earth, putting it at twice the distance between the Earth and the Sun. This places it well beyond the orbit of Mars, and over halfway between Mars and Jupiter.

At this distance, the Green Bank Telescope will take less than a minute to detect an omni-directional transmitter with the power of a cellphone. In other words, if there is a alien signal coming from this object, Breakthrough Listen is sure to sniff it out in no time! As Andrew Siemion, Director of Berkeley SETI Research Center and a member of Breakthrough Listen, explained in a BI press statement:

“‘Oumuamua’s presence within our solar system affords Breakthrough Listen an opportunity to reach unprecedented sensitivities to possible artificial transmitters and demonstrate our ability to track nearby, fast-moving objects. Whether this object turns out to be artificial or natural, it’s a great target for Listen.”

Even if there are no signals to be heard, and no other evidence of extra-terrestrial intelligence is detected, the observations themselves are a opportunity for scientists and the field of radio astronomy in general. The project will observe ‘Oumuamua in portions of the radio spectrum that it has not yet been observed at, and is expected to yield information about the possibility of water ice or the presence of a “coma” (i.e. gaseous envelop) around the object.

During the previous survey, data gathered using the VLT’s FOcal Reducer and low dispersion Spectrograph (FORS) indicated that ‘Oumuamua was likely a dense and rocky asteroid with a high metal content and little in the way of water ice. Updated information provided by the Greenbank Telescope could therefore confirm or cast doubt on this, thus reopening the possibility that it is actually a comet.

Regardless of what it finds, this survey is likely to be a feather in the cap of Breakthrough Listen, which already demonstrated it’s worth in terms of non-SETI astronomy this past summer. At that time, and using the Green Bank Radio Telescope, the Listen science team at UC Berkeley observed 15 Fast Radio Bursts (FRBs) for the fist time coming from a dwarf galaxy three billion light-years from Earth.

Still, I think we can all agree that an extra-terrestrial spaceship would be the most exciting possibility (and perhaps the most frightening!). And it is very safe to say that some of us will be awaiting the results of the survey with baited breath. Luckily, we’ll only have to wait two more days to see if humanity is still alone in the Universe or not! Stay tuned!

Further Reading: Breakthrough Initiatives

Breakthrough Detects Repeating Fast Radio Bursts Coming from Distant Galaxy

In July of 2015, Russian billionaire Yuri Milner announced the creation of Breakthrough Listen, a decade-long project that would conduct the largest survey to date for signs of extra-terrestrial communications (ETI). As part of his non-profit organization, Breakthrough Initiatives, this survey would rely on the latest in instrumentation and software to observe the 1,000,000 closest stars and 100 closest galaxies.

Using the Green Bank Radio Telescope in West Virginia, the Listen science team at UC Berkeley has been observing distant stars for over a year now. And less than a week ago, they observed 15 Fast Radio Bursts (FRBs) coming from a dwarf galaxy located three billion light-years away. According to a study that described their findings, this was the first time that repeating FRBs have been seen coming from this source at these frequencies.

The team’s study, titled “FRB 121102: Detection at 4 – 8 GHz band with Breakthrough Listen backend at Green Bank“, was recently published in The Astronomers Telegraph. Led by Dr. Vishal Gajjar – a postdoctoral researcher at the University of California, Berkeley – the team conducted a detailed survey of FRB 121102. This repeating FRB source is located in a dwarf galaxy in Auriga constellation, some 3 billion light-years from Earth.

The NSF’s Arecibo Observatory, which is located in Puerto Rico, is the world largest radio telescope. Credit: NAIC

To clarify, FRBs are brief, bright pulses of radio waves that are periodically detected coming from distant galaxies. This strange astronomical phenomena was first detected in 2007 by Duncan Lorimer and David Narkovic using the Parkes Telescope in Australia. To honor their discovery, FRBs are sometimes referred to as “Lorimer Bursts”. Many FRB sources have been confirmed since then, some of which were found repeating.

The source known as FRB 121101 was discovered back on November 2nd, 2012, by astronomers using the Arecibo radio telescope. At the time, it was the first FRB to be discovered; and by 2015, it became the first FRB to be seen repeating. This effectively ruled out the possibility that repeating FRBs were caused by catastrophic events, which had previously been theorized.

And in 2016, FRB 121102 was the first FRB to have its location pinpointed to such a degree that its host galaxy could be identified. As such, the Listen science team at UC Berkeley was sure to add FRB 121102 to their list of targets. And in the early hours of Saturday, August 26th, Dr. Vishal Gajjar – a postdoctoral researcher at UC Berkeley – observed FRB 121102 using the Green Bank Radio Telescope (GBRT) in West Virginia.

Using the Digital Backend instrument on the GBRT, Dr. Gajjar and the Listen team observed FRB 121102 for five hours. From this, they accumulating 400 terabytes of data in the entire 4 to 8 GHz frequency band which they then analyzed for signs of short pulses over a broad range of frequencies. What they found was evidence of 15 new pulses coming from FRB 121102, which confirmed that it was in a newly active state.

The Green Bank Telescope, located in West Virginia. Credit: NRAO

In addition, their observations revealed that the brightest of these 15 emissions occurred at around 7 GHz. This was higher than any repeating FRBs seen to date, which indicated for the first time that they can occur at frequencies higher than previously thought. Last, but not least, the high-resolution data the Listen team collected is expected to yield valuable insights into FRBs for years to come.

This was made possible thanks to the Digital Backend instrument on the GBRT, which is able to record several GHz of bandwidth simultaneously and split the information into billions of individuals channels. This enables scientists to study the proprieties and the frequency spectrum of FRBs with greater precision, and should lead to new theories about the causes of these radio emissions.

So even if these particular signals should prove to not be an indication of extra-terrestrial intelligence, Listen is still pushing the boundaries of what is possible with radio astronomy. And given that Breakthrough Listen is less than two years into its proposed ten-year survey, we can expect many more sources to be observed and studied in the coming years. If there’s evidence of ETI to be found, we’re sure to find out about it sooner or later!

And be sure to check out this video of the Green Bank Telescope and the surveys it allows for, courtesy of Berkeley SETI:

Further Reading: Breakthrough Initiatives

Breakthrough Listen Publishes First Analysis Of 692 Stars In ET Search

In July of 2015, Breakthrough Initiatives – a non-profit dedicated to the search for extra-terrestrial intelligence, founded by Yuri Milner – announced the creation of Breakthrough Listen. A ten-year initiative costing $100 million, this program was aimed at using the latest in instrumentation and software to conduct the largest survey to date for extraterrestrial communications, encompassing the 1,000,000 closest stars and 100 closest galaxies.

On Thursday, April. 20th, at the Breakthrough Discuss conference, the organization shared their analysis of the first year of Listen data. Gathered by the Green Bank Radio Telescope, this data included an analysis of 692 stars, as well as 11 events that have been ranked for having the highest significance. The results have been published on the project’s website, and will soon be published in the Astrophysical Journal.

Since 2016, Breakthrough Listen has been gathering data with the Green Bank Radio Telescope in West Virginia, the Lick Observatory’s Automated Planet Finder on Mt. Hamilton in California, and the Parkes Radio Telescope in Australia. This data is analyzed by the Listen science team at the Berkeley SETI Research Center (BSRC), who rely on a specially-designed data pipeline to scan through billions of radio channels for any sign of unique signals.

The Green Bank Telescope (GBT), a radio telescope located at the Green Bank Observatory in West Virginia. Credit: greenbankobservatory.org

While the results were not exactly definitive, this is just the first step in a program that will span a decade. As Dr. Andrew Siemion, the Director of the BSRC, explained in a BI press release:

“With the submission of this paper, the first scientific results from Breakthrough Listen are now available for the world to review. Although the search has not yet detected a convincing signal from extraterrestrial intelligence, these are early days. The work that has been completed so far provides a launch pad for deeper and more comprehensive analysis to come.”

The Green Bank Telescope searched for these signals using its “L-band” receiver, which gathers data in frequencies ranging from 1.1 to 1.9 GHz. At these frequencies, artificial signals can be distinguished from natural sources, which includes pulsars, quasars, radio galaxies and even the Cosmic Microwave Background (CMB). Within these parameters, the BSRC team examined 692 stars from its primary target list.

For each star, they conducting three five-minutes observation periods, while also conducting five-minute observations on a set of secondary targets. Combined with a Doppler drift search – a perceived difference in frequency caused by the motion of the source or receiver (i.e. the star and/or Earth) – the Listen science team identified channels where radio emission were seen for each target (aka. “hits”).

The Parkes radio telescope, one of the telescopes comprising CSIRO’s Australia Telescope National Facility. Credit: CSIRO/David McClenaghan

This led to a combined 400 hours and 8 petabytes worth of observational data. All together, the team found millions of hits from the sample data as a whole, and eleven events that rose above the threshold for significance. These events (which are listed here) took place around eleven distant stars and ranged from to 25.4 to 3376.9 SNR (Signal-to-Noise Ratio).

However, the vast majority of the overall hits were determined to be the result of radio frequency interference from local sources. What’s more, further analysis of the 11 events indicated that it was unlikely that any of the signals were artificial in nature. While these stars all exhibited their own unique radio “fingerprints”, this is not necessarily an indication that they are being broadcast by intelligent species.

But of course, finding localized and unusual radio signals is an excellent way to select targets for follow-up examination. And if there is evidence to be found out there of intelligent species using radio signals to communicate, Breakthrough Listen is likely to be the one that finds them. Of all the SETI programs mounted to date, Listen is by far the most sophisticated.

Not only do its radio surveys cover 10 times more sky than previous programs, but its instruments are 50 times more sensitive than telescopes that are currently engaged in the search for extra-terrestrial life. They also cover 5 times more of the radio spectrum, and at speeds that are 100 times as fast. Between now and when it concludes in the coming decade, the BSRC team plans to release updated Listen data once every six months.

Aerial view of the Automated Planet Finder at the Lick Observatory. Credit: Lick Observatory/Laurie Hatch

In the meantime, they are actively engaging with signal processing and machine learning experts to develop more sophisticated algorithms to analyze the data they collect. And while they continue to listen for extra-solar sources of life, Breakthrough Starshot continues to develop the first concept for a laser-driven lightsail, which they hope will make the first interstellar voyage in the coming years.

And of course, we here in the Solar System are looking forward to missions in the coming decade that will search for life right here, in our own backyard. These include missions to Europa, Enceladus, Titan, and other “ocean worlds” where life is believed to exist in some exotic form!

Breakthrough Listen‘s data analysis can be found here. Director Andrew Siemion also took to Facebook Live on Thursday, April 20th, to presents the results of Listen’s first year of study.And be sure to check out this video that marked the launch of Breakthrough Initiatives:

Further Reading: Breakthrough Initiatives, Berkeley SETI

 

The Search Is On For Alien Signals Around Tabby’s Star


There’s a remote chance that inexplicable light variations in a star in the Northern Cross may be caused by the works of an alien civilization.

1,480 light years from Earth twinkles one of the greatest mysteries of recent times.  There in the constellation Cygnus the Swan, you’ll find a dim, ordinary-looking point of light with an innocent sounding name — Tabby’s Star.  Named for Louisiana State University astronomer  Tabetha Boyajian, who was the lead author on a paper about its behavior, this star has so confounded astronomers with its unpredictable ups and downs in its brightness, they’ve gone to war on the object, drilling down on it with everything from the Hubble to the monster 393.7-inch (10-meter) Keck Telescope in Hawaii.

Tabby’s Star was uncovered by the Kepler Space Telescope during its examination of of more than 150,000 stars in the Milky Way. Kepler sought out stars accompanied by planets. By recording tiny, repeating fading of the star’s light as a planet passes in front a star, astronomers could determine the planet’s size, orbit and much more. All told, Kepler nabbed more than 2,300 new planets orbiting a host of stars in the constellations Lyra and Cygnus.

This graph shows the big dip in brightness of KIC 8462852 around 800 days (center) followed after 1500 days whole series of dips of varying magnitude up to 22%. The usual drop in light when an exoplanet transits its host star is a fraction of a percent. The star’s normal brightness has been set to “1.00” as a baseline. Credit: Boyajian et. all
This graph shows the big dip in brightness of KIC 8462852 around 800 days (center) followed after 1500 days whole series of dips of varying magnitude up to 22%. The usual drop in light when an exoplanet transits its host star is a fraction of a percent. The star’s normal brightness has been set to “1.00” as a baseline. Credit: Boyajian et. all

Among the stars Kepler viewed in its survey was one KIC 8462852 (Tabby’s Star). Unlike the others, its light dimmed in a completely unpredictable way. Things in orbit produce repeatable patterns, so astronomers began searching for alternative explanations. Might the star be variable? Lots of stars undergo physical changes such as pulsations or even explosions that cause them to vary in brightness. Nope. Based on its type, a stable star similar to the sun, and the fact that most of the time, it remains shining with a steady light, it didn’t fit the pattern.

Tabby's Star shines at magnitude +11.7 in the constellation Cygnus the Swan (Northern Cross) high in the southwestern sky at nightfall in late October. A 6-inch or larger telescope will easily show it. Source: Stellarium
Tabby’s Star shines at magnitude +11.7 in the constellation Cygnus the Swan (Northern Cross) high in the southwestern sky at nightfall in late October. A 6-inch or larger telescope will easily show it. Source: Stellarium

The star dims by as much as 22% for days at a time at irregular intervals. Stars fade and re-brighten, but not in the way this star does according to astronomers. Researchers ruled out many possibilities including instrumental errors, starspots (like sunspots but on other stars), dust rings seen around young, evolving stars (this is an older star) and pulsations that can cloak it with light-absorbing dust clouds. Dust clouds don’t work because they’d warm up in the star’s light and radiate heat that we could detect with infrared telescopes. We see no excess of glowing dust, ruling that possibility out, too.

Casting about for potential answers, Boyajian and team hit on the hypothesis that an enormous cloud of comets might be behind the light fluctuations. Imagine these comets, fragile creatures that they are, breaking up into fragments that cascade into smaller pieces over time, creating a host of irregular and chaotic variations in Tabby’s light.

Artist's impression of an orbiting swarm of dusty comet fragments around Tabby's Star. Could these be responsible for its peculiar dips in brightness or is there a biological reason?  A small red dwarf star (above, left) lies near Tabby's. Credit: NASA/JPL-Caltech
Artist’s impression of an orbiting swarm of dusty comet fragments around Tabby’s Star. Could these be responsible for its peculiar dips in brightness or is there a biological reason?  A small red dwarf star (above, left) lies near Tabby’s. Credit: NASA/JPL-Caltech

While that may be a reach, there’s even a stranger possibility.  Jason Wright, an assistant professor of astronomy at Penn State, would like us to consider an alien civilization as the cause. Although the possibility is a remote one, he asks us to consider that an alien civilization may be building a megastructure known as a Dyson Sphere around its home star. A Dyson Sphere is a hypothetical sphere constructed around a star. Built of enormous solar panels, it would capture the star’s energy and convert it into electricity to power a technological civilization.

Now imagine if you will, thousands of huge panels in various stages of construction and position orbiting Tabby’s Star, and you just might have an explanation for its mysterious ups and downs. Far-fetched? Of course. But there may be a way to prove it.

The Green Bank Telescope is the world’s largest, fully-steerable telescope. The GBT’s dish is 100-meters by 110-meters in size, covering 2.3 acres of space. The telescope is currently being used in a new SETI (Search for Extraterrestrial Intelligence) attempt to look for possible alien radio signals from Tabby's Star. Credit: NRAO/AUI/NSF
The Green Bank Telescope is the world’s largest, fully-steerable telescope. The GBT’s dish is 100-meters by 110-meters in size, covering 2.3 acres of space. The telescope is currently being used in a new SETI (Search for Extraterrestrial Intelligence) attempt to look for possible alien radio signals from Tabby’s Star. Credit: NRAO/AUI/NSF

A technologically advanced civilization would presumably need to communicate over long distances just like humans do. We use radio and TV, both of which transmit at very specific and narrow frequencies. Every time you go up and down the radio dial, each station you hear is beaming powerful radio waves at a specific frequency or vibration rate. Natural processes are more casual with a broader spread of frequencies. If we could detect a powerful signal at a specific frequency coming from Tabby’s Star, it could potentially be an indication of an alien species at work transmitting their own version of Dancing with the Stars.

One possibility for the weird light variations from Tabby's Star might be a Dyson Sphere built by an alien civilization around the star to harness its power. Credit: UC Berkeley
One possibility for the weird light variations from Tabby’s Star might be a Dyson Sphere built by an alien civilization around the star to harness its power. Credit: UC Berkeley

So how do we do this? How can even know what frequencies they’ll be using to transmit? Well, you take the Green Bank Radio Telescope, the largest fully steerable radio telescope on the planet, and hook it up with a new SETI instrument that can look at an enormous swath of bandwidth simultaneously in billions of different radio channels. That’s exactly what happened Wednesday night (Oct. 26) as part of the Breakthrough Listen project, a $100 million initiative by Russian tycoon Yuri Milner to search for intelligent life in the universe.  

University of California Berkeley astronomers devoted eight hours of scope time last night “listening” to Tabby’s Star for potential signs of an extraterrestrial civilization. They’ll spend two more nights in the coming two months at it and then analyze the data, a process that will take more than a month. Perhaps then we’ll finally get an answer. I hope it’s an alien one, but of course that’s a long shot. Stay tuned.

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Is Alpha Centauri The Best Place To Look For Aliens?

For generations, human beings have fantasized about the possibility of finding extra-terrestrial life. And with our ongoing research efforts to discover new and exciting extrasolar planets (aka. exoplanets) in distant star systems, the possibility of actually visiting one of these worlds has received a real shot in the arm. Unfortunately, given the astronomical distances involved, not to mention the cost of mounting an expedition, doing so presents numerous significant challenges.

However, Russian billionaire Yuri Milner and the Breakthrough Foundation – an international organization committed to exploration and scientific research –  is determined to mount an interstellar mission to Alpha Centauri, our closest stellar neighbor, in the coming years. With the backing of such big name sponsors as Mark Zuckerberg and Stephen Hawking, his latest initiative (named “Project Starshot“) aims to send a tiny spacecraft to the Alpha Centauri system to search for planets and signs of life.

Continue reading “Is Alpha Centauri The Best Place To Look For Aliens?”