Noah's Search: Probing Satellite Imagery for Lost Ark

Moviegoers were recently treated to "Noah," an epic story of bravery and sacrifice from the Old Testament, a saga in which the titular character takes on the divine mission to build an ark to save creation from an apocalyptic deluge.

Outside the big screen, speculation has swirled for decades that the leftovers of Noah's Ark hug the heights of Mt. Ararat in eastern Turkey — at a spot known as the Ararat anomaly. In true detective jargon, call it an "anomaly of interest."

Satellite imagery and analysis may make it possible to resolve the mystery. [Satellite Quiz: How Well Do You Know What's Orbiting Earth?]

Porcher Taylor, a professor of paralegal studies in the School of Professional and Continuing Studies at the University of Richmond, has led the search into the Mt. Ararat anomaly. Taylor's quest began long ago, he said.

"The cognitive genesis of my journey began in 1973, some 41 years ago, in my junior year as a cadet at West Point," he told Space.com. Back then, Taylor came across "credible rumors" ricocheting off the walls of the academy that a CIA spy satellite had accidentally imaged "what appeared to be the bow of a ship sticking up out of the ice cap on Mt. Ararat," Taylor said.

A couple of decades later, Taylor launched his own satellite declassification initiative investigating the Mt. Ararat anomaly imagery.

Drawing on his  21 years of arm-chair sleuthing, Taylor has given unclassified presentations at the Pentagon and the U.S. Naval Surface Warfare Center.

Along the way, he declared victory in convincing the Defense Intelligence Agency in 1995 to declassify five 1949 U.S. Air Force aerial photos of Mt. Ararat. Additionally, thanks to Taylor's invitations, a number of experts over the years have "performed analyses of the satellite imagery, which thankfully tempered my zeal as an amateur," Taylor said.

Biblical proportions

So in this day and age, why continue the journey? The wealth of information provided by DigitalGlobe's satellite imagery keeps Taylor going, he said.

"My ultimate goal has always been that my acquisition over the years of progressively higher- and higher-resolution satellite imagery from DigitalGlobe of the anomaly might definitively change the anomaly into a known entity, either something geological or perhaps something of Biblical proportions," Taylor said.

DigitalGlobe's new and powerful WorldView-3 spacecraft is slated for launch from California'sVandenberg Air Force Base in summer 2014. Among its customer-provided attributes, the satellite will yield 31-centimeter (12 inches) panchromatic resolution, making it the highest-resolution commercial satellite in the world.

"DigitalGlobe's constellation of satellites would be the envy of Indiana Jones," Taylor told Space.com. "I'm grateful and humbled that Digital Globe has flown numerous gratis missions for me over Mt. Ararat over the past decade, especially the QuickBird satellite mission of February 2003 that captured the boat-like form of the anomaly at 15,000 feet, without excessive amounts of snow and ice cover." [See images from Digital Globe]

Precise view

Similar technology has already secured valuable scientific data for other purposes. Satellite imagery has proven to be a valuable tool for providing accurate information about the changing planet, said Kumar Navulur, senior director at DigitalGlobe's Product Development & Labs in Longmont, Colorado.

"State-of-the-art remote-sensing technology and analytics are now so advanced, we can not only view detailed information about man-made features, but also monitor the wonders of some of Mother Nature's hidden treasures," Navulur told Space.com. "For example, we have mapped polar bear patterns in the Arctic and penguin populations in the Antarctic," he said.

Navulur said that satellite imagery provides such a precise view from space "that we are able to proactively observe environmental changes which unravel human footprints from thousands of years ago, such as the Ararat anomaly, and contribute to space archeology in a real and meaningful manner."

Taylor hopes that a future DigitalGlobe satellite image might catalyze a scientific organization like National Geographic to launch an expedition to explore up under the ice cap on Mt. Ararat's Western Plateau at the 15,000-foot level.

The "game-changing" WorldView-3 satellite, Taylor said, "might just accomplish that goal, as that will be the world's first commercial satellite to have that skill set … a quantum leap in satellite technology!"

Dogged determination

Additional analytical techniques have aided Taylor in his mission. He recently made use of a panchromatic texture uniqueness analysis of the anomaly, provided by remote sensing researcher and Ph.D. candidate Francois Luus from the Department of Electrical, Electronic and Computer Engineering at the University of Pretoria, South Africa, and Luus' research supervisor, Sunil Maharaj.

Imagery used in the work was gleaned by the QuickBird satellite mission at 61 centimeters resolution in 2003. All the details of that recent analysis of the Mt. Ararat anomaly can be found in the following six-page report at:http://goo.gl/f8O3gs

Luus told Space.com that Taylor displays the tenacity and dogged determination characteristic of a successful investigator.

"His ability to rally support and repeatedly obtain specially commandeered satellite imagery of the Ararat anomaly is inspiring," Luus said.

Solving the riddle

Luus' texture analysis completed will help Taylor and others determine the anomaly's identity, Luus said.

"The texture uniqueness analysis we performed provides a more objective artificial intelligence perspective that shows us the parts of the anomaly that have novel textures and warrant further investigation," Luus said. "As a remote-sensing researcher, every pixel is given its due consideration, and good imagery is invaluable," he said.

Further study may consider the locations pinpointed by the uniqueness search to find clues about an artifact underlying the anomaly, Luus said.

"We are very excited about the new DigitalGlobe WorldView-3 satellite, which can truly shed some new light on the anomaly with its very high panchromatic and multispectral resolutions," Luus said. "Imagery of this quality may finally solve the riddle of the Ararat anomaly, or at least become the subject of a very satisfying remote sensing analysis," he said.

Source: Space.com 

Mystery object in lake on Saturn's moon Titan intrigues scientists

Nasa's Cassini probe took image last year as it passed by planet's largest moon – nothing seen when other images taken

The mystery object, described as a 'magic island' appeared out of nowhere in radar images of a hydrocarbon sea on Saturn's giant moon, Titan. Photograph: JPL-Caltech/ASI/Cornell/NASA/PA

Scientists are investigating a mystery object that appeared and then vanished again from a giant lake on Titan, the largest moon of Saturn.

They spotted the object in an image taken by Nasa's Cassini probe last year as it swung around the alien moon, more than a billion kilometres from Earth. Pictures of the same spot captured nothing before or some days later.

Little more than a white blob on a grainy image of Titan's northern hemisphere, the sighting could be an iceberg that broke free of the shoreline, an effect of rising bubbles, or waves rolling across the normally placid lake's surface, scientists say.

Astronomers have named the blob the "magic island" until they have a better idea what they are looking at. "We can't be sure what it is yet because we only have the one image, but it's not something you would normally see on Titan," said Jason Hofgartner, a planetary scientist at Cornell University in New York. "It is not something that has been there permanently."

Titan is one of the most extraordinary places in the solar system. The land is strewn with hydrocarbon dunes that rise above lakes fed by rivers of liquid methane and ethane. The atmosphere is so thick, and the gravity so weak, that a human could strap on wings and flap into the air. That air is laced with lethal hydrogen cyanide.

The largest moon of Saturn – there are more than 60 smaller ones – is the only place beyond Earth known to have stable liquids on its surface and rain falling from its skies. Spacecraft have mapped scores of lakes there. The three biggest are named after mythological beasts, the Kraken, Ligeia and Punga, and are large enough to qualify as seas, or mares.

The US team made their curious discovery while poring over radar images of Ligeia mare, a 150-metre-deep sea that stretches for hundreds of kilometres in Titan's northern hemisphere. Among the snapshots taken in 2007, 2009 and 2013 was one with the strange white feature, about six miles off the mountainous southern shore.

NASA handout photo dated 26/04/07 of the area in Titan's Ligeia mare before the object was seen (top) and 10/07/13 of the 'magic island'. Photograph: JPL-Caltech/ASI/Cornell/NASA/PA

Roughly 12 miles long and six miles wide, the bright spot appears in an image dated 10 July 2013 but is missing from pictures of the same spot taken previously and on 26 July. Hofgartner said the team had ruled out any errors in the radar imaging equipment that could result in the blob.

Through a process of elimination, the scientists have whittled the number of potential explanations down to four. It could be one or more icebergs floating around, or material in suspension beneath the surface. But Cassini's radar might also have picked upseen a rush of bubbles coming from the depths of the sea, or captured the first signs of deep-sea waves on Titan.

Last year's Cassini fly-by found that Ligeia mare, Titan's second-largest lake, was as smooth as glass. The tranquil expanse of liquid methane and ethane had no waves or surface ripples larger than 1mm.

The profound stillness may be because the wind on Titan is so feeble. But that could be changing. Titan's orbital path and tilted axis make for seasons that last for seven Earth years. The northern hemisphere is gently warming now, as spring gives way to summer, which arrives in earnest in 2017. Warmer weather brings stronger winds, and stronger windswhich bring waves.

"This may be waves picking up. The sun is shining brighter, and that energy can be powering the winds. All you would need is a light breeze, around half a metre per second," said Hofgartner, whose study appeared in the journal Nature Geoscience.

But the wind on Titan may never be strong enough to stir truly impressive waves. "If you had a large enough surfboard, you could certainly float there, but I don't think you'd really get the waves you'd want," Hofgartner said. The hydrocarbon seas, he added, are a chilly -180C.

If waves are the cause of the curious white blob, then Cassini spotted them before they had spread more widely across the sea. Follow-up images in the next few months are expected to shed more light on the mystery.

"We now have the first tantalising glimpse of some sort of dynamical process in one of Titan's largest seas," said John Zarnecki, professor ofspace science at the Open University.

"The observations with Cassini's radar are close to the limit of sensitivity so hard to interpret. But they do seem to be the first sign of something going on in the sea. Is it floating solids or erupting gas bubbles from below or wave action? We just don't know. The one thing we can say with certainty is that we just have to go back to Titan – but this time with a sea floater so that we can see close up just what is happening in the seas of this incredible place."

In March, some of the researchers who worked with Hofgartner reported what may have been glimpses of tiny waves on another Titan sea, called Punga mare. Instruments aboard Cassini found that sunlight reflecting off the sea was brighter than expected in places, an effect that could be caused by waves lapping at the shore.

Nasa has toyed with the idea of sending a boat to sail on the seas of Titan, but the proposal lost out to a mission to Mars. There are still hopes of exploring the moon with two other Nasa missions. One would fly a balloon on Titan and release a drone to map the surface. The other aims to drop a submarine into the largest of Titan's seas, the 300-metre-deep Kraken mare.

Source: The Guardian

SPACEX UNVEIL NEW MARS PASSENGER SPACESHIP

A company that has flown unmanned capsules to the Space Station unveiled a spacecraft designed to ferry up to seven astronauts to low-Earth orbit that SpaceX founder Elon Musk says will lower the cost of going to space.

The futuristic, cone-headed craft dubbed Dragon V2 featured landing legs that pop out and a propulsion system designed to land almost anywhere “with the accuracy of a helicopter,” Musk said Thursday at the Southern California rocket builder’s headquarters near Los Angeles International Airport.

The technology would enable rapid reloading and reusability of the spacecraft, he said. He noted that in the past, many rockets and space craft return to Earth in a fireball, rendering them unusable.

“You can just reload, propel it and fly again,” Musk said. “This is extremely important for revolutionizing access to space because as long as we continue to throw away rockets and space crafts, we will never truly have access to space. It’ll always be incredibly expensive.”

The capsule also features a bright, sleek interior with swing-up computer screens at the control station, a two-level seating system to accommodate up to seven astronauts and large windows for them to marvel at Earth’s curvature.

The cone-shaped cap can open to allow for the manned craft to dock at the Space Station on its own.

The spacecraft also has more powerful engines, better heat shields, the landing legs and backup parachutes to ensure a soft landing.

In a NASA briefing with reporters last year, Musk said Dragon V2 would look futuristic like an “alien spaceship” and promised “it’s going to be cool.”

Since the shuttle fleet retired in 2011, NASA has depended on Russian rockets to transport astronauts to orbit and back, paying nearly $71 million per seat. The space agency has said it wants U.S. companies to fill the void by 2017 and has doled out seed money to spur innovation.

SpaceX short for Space Exploration Technologies Corp, has made four cargo runs to the giant orbiting outpost some 200 miles above Earth. Just last month, its Dragon capsule splashed into the Pacific, returning nearly 2 tons of science experiments and old equipment.

Companies competing for the right to ferry station astronauts need to design a spacecraft that can seat a crew of four or more and be equipped with life support systems and an escape hatch in case of emergency. SpaceX has said it’s designing a seven-seat spacecraft.

SpaceX and longtime NASA contractor Boeing Co. are “more or less neck and neck” in the competition, but there’s a long way to go before astronauts can rocket out of the atmosphere on private spacecraft, said John Logsdon, professor emeritus of political science and international affairs at George Washington University.

Logsdon said progress by private companies is slower than anticipated mainly because Congress has not fully funded NASA’s budget request for the effort. He said it’s important for the U.S. to wean its reliance on Russia given the political tension over the annexation of Crimea.

“It’s essential to have our own capability to transport people to space,” he said. “This is an important step in that direction.”

Firing Missiles at Mars – What Could Possibly Go Wrong?

It doesn’t take a rocket scientist to figure out that a group trying to raise money to shoot missiles at Mars is from the U.S. No matter what the reason, is blasting holes in another planet a good idea? And what IS their reason anyway?

Explore Mars, a non-profit group in Beverly, Massachusetts, is appealing for funds for a project it calls Exolance, whose purpose would be to probe deeper into the surface of Mars than any previous missions by firing missiles into the planet’s crust. The missiles would contain instruments design to withstand the impact so they can radio subterranean data back to Earth – data that Exolance hopes will include evidence of life on Mars.

Curiosity’s drill can only dig about an inch. NASA’s upcoming InSight lander mission will dig down five meters but isn’t looking for life, while the European Space Agency’sExoMars rover will probe two meters for life but only in one spot.

Exolance uses archery metaphors to explain its plan. The Arrows are small, lightweight penetrating probes originally designed for the military (bunker-busting weapons technology) that will pierce the surface to a depth of five or more meters. The life-detection equipment will send data to a surface transmitter which relays it to an orbiter that sends it to Earth. Multiple Arrows will be shot by a Quiver dispenser as it descends to the surface, so that they are spread across a wide surface area.

Explore Mars will test Exolance in the Mojave Desert in 2014 to prove the instruments can withstand the impact. Then it needs to convince NASA, SpaceX or another private company to take the probes to Mars as part of another mission.

NASA sent two penetrating probes to Mars in 1999 but the shock of impact knocked out the instruments. It has fired probes into sand and ice for a possible mission to Jupiter’s moon Europa.

Missiles, bunker-busting, arrows, penetration … not exactly terminology that says peaceful space exploration. What could possibly go wrong?

Source: MU

Bus-Sized Asteroid Makes Close Pass by Earth…but That’s Not the Scariest Part

A bus-sized asteroid passed by the Earth at a distance closer than the moon Saturday — but the more disconcerting part is how little warning astronomers had of the event.

Scientists learned of the 25-foot asteroid named 2014 HL129 just three days before it came within 186,000 miles of Earth.

The asteroid was spotted by astronomers with the Mt. Lemmon Survey, located in the Catalina Mountains of Arizona.

Watch this animation of HL129′s trajectory: HERE

Though Saturday’s event was only a close shave, incidents like the 65-foot-wide meteor that crashed in Russia in February 2013 — which went undetected until it was too late — are why NASA and other government space agencies around the world are working to better predict these giant space rocks that can have catastrophic consequences.

NASA’s Near-Earth Object Program estimates that more than 90 percent of the near-Earth objects larger than one kilometer have already been discovered, but 90 percent of those 140 meters or larger are still being tracked down.

Last year, NASA announced the Asteroid Grand Challenge, which encouraged the general public to get involved in the various aspects of asteroid hunting. Watch NASA’s video about this project:

But what’s to be done if a threatening asteroid is found? NASA is working on ideas to take care of that problem, too. One option includes sending up a weighted robotic spacecraft to collide with the object to send it off course, but this would require years of prior warning. Other ideas involve nuclear explosions or a spacecraft that could serve as a “gravity tractor” and change an asteroid’s velocity just enough to avoid a collision with the planet.

NASA’s Near Object Program has more detailed information about HL129.

Source: The Blaze

Fast Radio Bursts (FRBs): Natural Phenomena or ET Signal?

Astronomers have been scratching their heads over a series of mysterious radio bursts, so rare & intense, up until recently many of them even questioned their cosmic origin. First detected in 2007 through a telescope in Australia, the radio signals are known as fast radio bursts (FRBs) or Lorimer bursts, in honor of West Virginia University astrophysicistDuncan Lorimer, who was the first to discover & describe them on a scientific paper.

Since then, fewer than a dozen FRBs have been detected, the last one by the Arecibo observatory in Puerto Rico, on November 2, 2012 --as reported by National Geographic 2 weeks ago. By now we've only established 3 factors about the bursts: They are incredibly fast (lasting only a few milli-seconds), incredibly bright, and they seem to come from really, REALLY far away (as in billions of light years away).

But what causes them?

Because the signals are so brief and bright, they must be coming from a rather dense source, says astronomer Scott Ransom of the National Radio Astronomy Observatory. “That means a compact object – i.e., a neutron star or a black hole – is likely somehow to blame,” he says.
Just what that compact object is has yet to be explained. One theory suggests that giant flares erupting from highly magnetic neutron stars, known as magnetars, cause the bursts. Others suggest the bursts result from colliding neutron stars or black holes, evaporating primordial black holes, large magnetic stars, or are the death spasms produced when massive, slowly spinning neutron stars collapse into black holes. That last object, proposed in 2013, is known as a blitzar.

Notice that all these hypotheses have 1 thing in common: they assume the bursts are caused by some natural, albeit exotic phenomena. But would it be so ludicrous to speculate that FRBs have an artificial origin? That's what I humbly proposed on my Mysterious Universe column last week; something that could be easily dismissed as the nonsensical delusions of a woo-woo schmuck...

Well, turns out I'm not the only schmuck wondering about FRBs: In a comment left at the NatGeo page, none other than SETI founder Frank Drake is also proposing these mysterious bursts might be good candidates for a signal sent by some advanced civilization:

Indeed, [...] it is a worthy speculation that the FRBs might be a “hailing” message from a distant altruistic civilization. For many years, SETI scientists have speculated about the possible design of a hailing signal — a signal which announces loudly the existence of another civilization, and possibly leads the receiving civilization to a radio channel bearing much information. Without knowing which stars might be the home of other intelligent civilizations, the sending civilization might well adopt a strategy of sending hailing signals to large numbers of potential ETI-supporting stars. To achieve maximum probability of discovery, the right strategy is to send a very narrow-beam, powerful signal. In this case, one can send to only one star at a time, and so the strategy leads to a paradigm in which the transmitting beam is steered to a large number of stars sequentially, leading to the signals being detected possibly as short bursts which may repeat after some long time period. So we should search for more FRBs!

The famous 'Wow!' signal, detected on August 15, 1977, which to this day is still considered the signal closest to filling the criteria of what intelligent ETs would be transmitting through outer space --or at least, the criteria of what modern science currently assumes intelligent ETs would be capable of doing…

There was also a time, when astronomers seriously considered the possibility that pulsars were actually alien beacons, perhaps built & used by some incredibly powerful space-faring civilization, to help them navigate through the stellar oceans. The fact that both pulsars are now largely considered a natural phenomenon --the same as FRBs-- IMO speak of the current paradigm incongruence we're stuck in: On the one hand, scientists assure us that intelligent life is more than likely widespread throughout the Cosmos; but on the other hand, to propose an observed astronomical event as a sign of these assumed extraterrestrial civilizations, is still largely regarded as a wild speculation --Martian face, anyone?

Source: Daily Grail

Recharge Your Cosmic Awe With These Images Of Galaxies In Deep Space

It's really hard to remember that we live in a beautiful, insane universe, crammed with astonishing miracles of creation. So as a public service, we're sharing some absolutely stunning images of galaxies in deep space. Look at these, and remember to reach for greatness!

Arp 227 (a shell galaxy named NGC 474 and the blue spiral galaxy called NGC 470) and NGC 467, surrounded by faint shells, an evidence of another interacting galaxy system, within the boundaries of the constellation Pisces, some 100 million light-years distant. 

Galaxies on a Collision Course in the Hubble Ultra Deep Field Image, a small region of space in the constellation Fornax, photographed between September 2003 and January 2004 by the Hubble Space Telescope. This image contains at least 10,000 galaxies that existed between 400 and 800 million years after the Big Bang.

A "Big Baby" galaxy in the Hubble Ultra Deep Field

Abell 2218, a galaxy cluster about 2.1 billion light-years from the Earth in the northern constellation of Draco. It not only magnifies the images of hidden galaxies, but also distorts them into long, thin arcs.

Abell 68, a galaxy cluster about 2 billion light-years away. The fuzzy collection of blobs in the middle and upper left is a swarm of galaxies, each with hundreds of billions of stars.

NGC 7769, 7770 and 7771 , in the constellation Pegasus, about 200 million light-years away

A trio of galaxies often called the Draco Group, located in the northern constellation of Draco. From left to right: the edge-on spiral NGC 5981, the elliptical NGC 5982 and the face-on spiral NGC 5985, about 100 million light-years from us

Source: io9

This Immersive Video Makes You Feel Like You're Floating Upside Down

For a dizzying start to your week, grab your headphones and watch Underlapse at full screen. This time-lapse video takes you around an inverted world and screws with your brain in the process.

By altering the position of spatial cues, floating the Earth above our heads and suggesting the motion of clouds beneath our feet, Underlapse creates an unnerving experience, one that makes the familiar world a touch foreign. But even if you feel a little lost in inverted space, it's hard not to appreciate the view.

Déjà Vu: Bright Fireball Explodes Over Russia (Video)

Russians may be forgiven for thinking the sky is falling.

A super-bright meteor exploded over the northern Russian city of Murmansk early Saturday morning (April 19), a little more than a year after another airburst lit up the skies above Chelyabinsk, about 1,300 miles (2,090 kilometers) to the southeast.

Source: Space.com

Mars Missions Could Make Humanity a Multi-Planet Species, NASA Chief Says

In order for humanity to survive into the distant future, we need to visit and learn how to survive on other worlds, according to NASA chief Charles Bolden.

NASA is in the process of developing technologies that are expected to help humans get to Mars and beyond. Landing astronauts on Mars and even establishing a long-term human presence on the Red Planet is just one step toward learning how to live on a different world, Bolden said during the Humans 2 Mars Summit in Washington, D.C., Tuesday (April 22).

"If this species is to survive indefinitely, we need to become a multi-planet species," Bolden said. "One reason we need to go to Mars is so that we can learn a little bit about living on other planets ... Mars is a steppingstone in the steppingstone approach to other solar systems and other galaxies and things that people have always dreamed of but frequently don't talk about." [The Boldest Mars Missions in History]

deally, the first crewed mission to Mars will represent the culmination of many incremental steps — like NASA's ambitious plan to retrieve an asteroid and park it near the moon — taken to safely get humans to and from Mars, NASA officials have said.

Under the space agency's current framework, NASA officials hope to launch humans to Mars by the 2030s after sending an astronaut crew to an asteroid by 2025.

"We, today, are Earth-reliant," Bolden said. "We're dependent on being on this planet. We are not a multi-planet species yet … Only multi-planet species survive for long periods of time."

In general, the architecture for a mission to Mars is not like the Apollo program that brought astronauts to the moon for the first time. The current plan could involve sending multiple spacecraft to the Mars system over the course of years, however, the plan to get to Mars is an evolving process, William Gerstenmaier, NASA's associate administrator for the agency's human exploration and operations mission directorate, said during the conference today.

"We're starting to take a different approach toward Mars than we have before," Gerstenmaier said. "Our classic [ideas for Mars] missions were more Apollo-style in a way — where we launched everything within a year and we sent the armada of spacecraft … toward Mars. I think we're going to do that maybe over a period of time, over a period of years and build more of an evolvable piece.

"It's not a single mission, but it really is the pioneering aspect," Gerstenmaier added. "Once that mental change starts … and you're looking at it in the long term, then you invest in some things that might actually take longer to go do, but they may be more sustainable."

Learning more about Mars also has tangible effects right now, Bolden said. Understanding the Red Planet could also help scientists peer into the past and future of Earth.

"Mars' formation and evolution are comparable to Earth’s and we know that at one time Mars had conditions suitable for life," Bolden wrote in a post on Space.com. "What we learn about the Red Planet may tell us more about our own home planet's history and future and help us answer a fundamental human question — does life exist beyond Earth?"

Source: Space.com

Arecibo Observatory Detects Mysterious, Energetic Radio Burst

A brief, blazing burst of radio waves detected by the Arecibo Observatorycould herald a turning of the tide for a peculiar class of cosmic signals. Until recently, the signals had only ever been detected by a telescope in Australia, a pattern that fueled doubts about their origin.

Fewer than a dozen of these bursts, lasting for only a few thousandths of a second, have ever been reported. Called “fast radio bursts,” the signals are cosmic enigmas that appear to come from the very, very distant universe. But since the first burst discovery in 2007, scientists have not only wondered what kind of cosmic object could produce such a tremendously bright, short-lived radio pulse – but have disagreed about whether the bursts are even celestial.

“There are more theories than there are bursts,” says West Virginia University astronomer Duncan Lorimer, an author on the paper describing the burst, posted to the arXiv on April 10.

On November 2, 2012, a blast of radio waves collided with the Arecibo Observatory in Puerto Rico, where the world’s largest single-dish radio telescope lives. Rain or shine, day or night, the 305-meter dish collects radio waves from the cosmos, which are then processed into data for scientists to study.

The data gathered at 6:35 am UT revealed a massive, 3-millisecond spike. Unlike the radio blasts emitted by some pulsars, the burst did not recur. It briefly blazed and then disappeared. Called FRB 121102, the burst was very similar to six earlier events that constitute the entire reported population of ultrafast radio bursts – a population that until November 2012 had only been seen by one telescope, in Australia.

But transience is only part of what makes these signals so weird. Their chief peculiarity lies in just how dang far away they seem to be.

Normally, radio waves travel at the speed of light. This means that all the different wavelengths and frequencies of radio waves emitted by the same object – say, a pulsar – should arrive on Earth in one big batch.

But if something is sufficiently far away, that changes. Longer, lower frequency waves traveling through the cosmos have a trickier time getting to Earth. Clouds of ionized interstellar particles – electrons, primarily – form roadblocks that slow and redirect these longer waves, causing them to follow a more sinuous path. As a result, the longer waves arrive just a bit later than their shorter kin – sometimes, the difference is only a fraction of a second.

That delay in arrival times is called “dispersion,” and it lets astronomers estimate how far away the waves are coming from. The longer the delay, the more intergalactic junk that got in the way. And since scientists think they know how much junk there is, they can use the dispersion measurement to approximate a distance, or at least identify whether an object lives inside or outside the Milky Way.

If astronomers are interpreting the bursts’ dispersion measures correctly, then the bursts came from billions and billions of light-years away – in other words, they’re nowhere near our cosmic neighborhood. And nobody knows what they are.

“The sources of the bursts are undoubtedly exotic by normal standards,” Cornell University astronomer Jim Cordes wrote in Science.

The ultrafast pulses take their name from Lorimer, who spotted and described the first burst in 2007. That mysterious signal, estimated to have traveled roughly 3 billion light-years before colliding with Earth, stunned astronomers. Many of them questioned whether it was an artifact produced by the telescope that detected it, the Parkes Observatory’s 64-meter telescope in Australia.

In the years after the discovery, skepticism grew. A new class of terrestrial radio bursts detected by the Parkes telescope in 2010 cast more doubt on the original Lorimer burst. Those Earth-based signals, called perytons, opened the door to the possibility that even if real, the original burst was actually coming from much closer to home.

Another Parkes-detected burst, reported in 2012, didn’t do much to alleviate doubts.

But that summer, a third Lorimer burst was described at the International Astronomical Union’s general assembly in Beijing, China; as it turned out, this burst would be one member of a quartet that astronomers would announce the next year in Science. By the end of July, 2013, the total reported stood at six.

“The discovery of fast radio bursts at the Parkes Observatory, if confirmed at other observatories, would be a monumental discovery, comparable to that of cosmological gamma-ray bursts and even pulsars,” Shrinivas Kulkarni, an astronomer at Caltech, told Scientific American at the time.

Strength in numbers was helping the bursts achieve legitimacy, but there was no escaping that they’d all been detected by the same telescope. And until another observatory saw something similar, skeptics could easily question whether the signals were a product of the telescope and its location, rather than the cosmos.

“In fairness, it’s not a bad question to ask at all,” Lorimer says. “Whenever you make a new discovery, it’s very important to have it confirmed by different groups, using different equipment.”

Now, the Arecibo detection of FRB 121102 strongly suggests the signals are not a Parkes artifact, and furthermore, that they’re not terrestrial in origin.

“I’m certainly very excited to see such a convincing result from another team using a different observatory,” says astronomer Michael Keith of the University of Manchester, who was not involved in the current study.

So the questions astronomers are asking are: How far have the bursts traveled? And what, exactly, are they?

“My hunch has always been that they’re extragalactic,” Lorimer says. “But that’s really nothing more than a hypothesis at this point.”

Overall, the dispersion measures do seem to suggest an extragalactic origin. There are many more electrons between Earth and the bursts than can be explained by the Milky Way’s interstellar electrons; but it’s still possible that intervening nebulas could be clouding the measurement, Kulkarni says. He suggests the signals could be coming from spinning neutron stars known as radio rotating transients, or RRATs, that live in our galaxy and also emit a single pulse.

Because the signals are so brief and bright, they must be coming from a rather dense source, says astronomer Scott Ransom of the National Radio Astronomy Observatory. “That means a compact object – i.e., a neutron star or a black hole – is likely somehow to blame,” he says.

Just what that compact object is has yet to be explained. One theory suggests that giant flares erupting from highly magnetic neutron stars, known as magnetars, cause the bursts. Others suggest the bursts result from colliding neutron stars or black holes, evaporating primordial black holes, large magnetic stars, or are the death spasms produced when massive, slowly spinning neutron stars collapse into black holes. That last object, proposed in 2013, is known as a blitzar.

More observations should help teams pinpoint the bursts’ origin. Already, more detections from Parkes are coming down the pipeline, and Ransom says he’s looking through the Green Bank Telescope’s data for similar signals. But what astronomers are really hoping for is a way to find the bursts in real-time – then, they might be able to identify an optical source, like a host galaxy. In addition to supporting an extragalactic origin, that would also allow scientists to use the bursts to probe the characteristics of the intervening intergalactic medium and its ions.

“We really need to get their precise positions,” Ransom says. “That will let us see where they originate – hopefully in or near other galaxies where we can get their distances.”

Source: National Geographic