Excerpt from spacedaily.comAccording to the new method, Saturn's day is 10 hours, 32 minutes and 44 seconds long. Tracking the rotation speed of solid planets, like the Earth and Mars, is a relatively simple task: Just measure the time it tak...
Tag: patterns (page 2 of 8)
Excerpt from theguardian.com
Whether it was a Druid temple, an astronomical calendar or a centre for healing, the mystery of Stonehenge has long been a source of speculation and debate. Now a dramatic new theory suggests that the prehistoric monument was in fact “an ancient Mecca on stilts”.
The megaliths would not have been used for ceremonies at ground level, but would instead have supported a circular wooden platform on which ceremonies were performed to the rotating heavens, the theory suggests.
Julian Spalding, an art critic and former director of some of the UK’s leading museums, argues that the stones were foundations for a vast platform, long since lost – “a great altar” raised up high towards the heavens and able to support the weight of hundreds of worshippers.
“It’s a totally different theory which has never been put forward before,” Spalding told the Guardian. “All the interpretations to date could be mistaken. We’ve been looking at Stonehenge the wrong way: from the earth, which is very much a 20th-century viewpoint. We haven’t been thinking about what they were thinking about.”
Since Geoffrey of Monmouth wrote in the 12th century that Merlin had flown the stones from Ireland, theories on Stonehenge, from plausible to absurd, have abounded. In the last decade alone, the monument has been interpreted as “the prehistoric Lourdes” where people brought the sick to be healed by the power of the magic bluestones from Wales and as a haunted place of the dead contrasting with seasonal feasts for the living at nearby Durrington Walls.
The site pored over by archaeologists for centuries still produces surprises, including the outline of stones now missing, which appeared in the parched ground in last summer’s drought and showed that the monument was not left unfinished as some had believed, but was once a perfect circle.
Spalding, who is not an archaeologist, believes that other Stonehenge theorists have fallen into error by looking down instead of up. His evidence, he believes, lies in ancient civilisations worldwide. As far afield as China, Peru and Turkey, such sacred monuments were built high up, whether on manmade or natural sites, and in circular patterns possibly linked to celestial movements.
He said: “In early times, no spiritual ceremonies would have been performed on the ground. The Pharaoh of Egypt and the Emperor of China were always carried – as the Pope used to be. The feet of holy people were not allowed to touch the ground. We’ve been looking at Stonehenge from a modern, earth-bound perspective.”
“All the great raised altars of the past suggest that the people who built Stonehenge would never have performed celestial ceremonies on the lowly earth,” he went on. “That would have been unimaginably insulting to the immortal beings, for it would have brought them down from heaven to bite the dust and tread in the dung.”
Spalding’s theory has not met with universal approval. Prof Vincent Gaffney, principal investigator on the Stonehenge Hidden Landscapes Project at Bradford University, said he held “a fair degree of scepticism” and Sir Barry Cunliffe, a prehistorian and emeritus professor of European archaeology at Oxford University, said: “He could be right, but I know of no evidence to support it”.
The archaeologist Aubrey Burl, an authority on prehistoric stone circles, said: “There could be something in it. There is a possibility, of course. Anything new and worthwhile about Stonehenge is well worth looking into, but with care and consideration.”
On Monday Spalding publishes his theories in a new book, titled Realisation: From Seeing to Understanding – The Origins of Art. It explores our ancestors’ understanding of the world, offering new explanations of iconic works of art and monuments.
Stonehenge, built between 3000 and 2000BC, is England’s most famous prehistoric monument, a UNESCO World Heritage site on Salisbury Plain in Wiltshire that draws more than 1 million annual visitors. It began as a timber circle, later made permanent with massive blocks of stone, many somehow dragged from dolerite rock in the Welsh mountains. Spalding believes that ancient worshippers would have reached the giant altar by climbing curved wooden ramps or staircases.
Originally Posted at in5d.com The following is the alleged result of the actions of one or more scientists creating a covert, unauthorized notebook documenting their involvement with an Above Top Secret government program. Government publications and information obtained by the use of public tax monies cannot be subject to copyright. This document is released into the public domain for all citizens of the United States of America. THE ‘MAJIC PROJECTS’ SIGMA is the project whic [...]
Excerpt from csmonitor.com
Researchers at Queen Mary University of London have found the first evidence of false memories in non-human animals.
It has long been known that humans – even those of us who aren't famous news anchors – tend to recall events that did not actually occur. The same is likely true for mice: In 2013, scientists at MIT induced false memories of trauma in mice, and the following year, they used light to manipulate mice brains to turn painful memories into pleasant ones.
Now, researchers at Queen Mary University of London have shown for the first time that insects, too, can create false memories. Using a classic Pavlovian experiment, co-authors Kathryn Hunt and Lars Chittka determined that bumblebees sometimes combine the details of past memories to form new ones. Their findings were published today in Current Biology.
“I suspect the phenomenon may be widespread in the animal kingdom," Dr. Chittka said in a written statement to the Monitor.
First, Chittka and Dr. Hunt trained their buzzing subjects to expect a reward if they visited two artificial flowers – one solid yellow, the other with black-and-white rings. The order didn’t matter, so long as the bee visited both flowers. In later tests, they would present a choice of the original two flower types, plus one new one. The third type was a combination of the first two, featuring yellow-and-white rings. At first, the bees consistently selected the original two flowers, the ones that offered a reward.
But a good night’s sleep seemed to change all that. One to three days after training, the bees became confused and started incorrectly choosing the yellow-and-white flower (up to fifty percent of the time). They seemed to associate that pattern with a reward, despite having never actually seen it before. In other words, the bumblebees combined the memories of two previous stimuli to generate a new, false memory.
“Bees might, on occasion, form merged memories of flower patterns visited in the past,” Chittka said. “Should a bee unexpectedly encounter real flowers that match these false memories, they might experience a kind of deja-vu and visit these flowers expecting a rich reward.”
Bees have a rather limited brain capacity, Chittka says, so it’s probably useful for them to “economize” by storing generalized memories instead of minute details.
“In bees, for example, the ability to learn more than one flower type is certainly useful,” Chittka said, “as is the ability to extract commonalities of multiple flower patterns. But this very ability might come at the cost of bees merging memories from multiple sequential experiences.”
Chittka has studied memory in bumblebees for two decades. Bees can be raised and kept in a lab setting, so they make excellent long-term test subjects.
“They are [also] exceptionally clever animals that can memorize the colors, patterns, and scents of multiple flower species – as well as navigate efficiently over long distances,” Chittka said.
In past studies, it was assumed that animals that failed to perform learned tasks had either forgotten them or hadn’t really learned them in the first place. Chittka’s research seems to show that animal memory mechanisms are much more elaborate – at least when it comes to bumblebees.
“I think we need to move beyond understanding animal memory as either storing or not storing stimuli or episodes,” Chittka said. “The contents of memory are dynamic. It is clear from studies on human memory that they do not just fade over time, but can also change and integrate with other memories to form new information. The same is likely to be the case in many animals.”
Chittka hopes this study will lead to a greater biological understanding of false memories – in animals and humans alike. He says that false memories aren’t really a “bug in the system,” but a side effect of complex brains that strive to learn the big picture and to prepare for new experiences.
“Errors in human memory range from misremembering minor details of events to generating illusory memories of entire episodes,” Chittka said. “These inaccuracies have wide-ranging implications in crime witness accounts and in the courtroom, but I believe that – like the quirks of information processing that occur in well known optical illusions – they really are the byproduct of otherwise adaptive processes.”
“The ability to memorize the overarching principles of a number of different events might help us respond in previously un-encountered situations,” Chittka added. “But these abilities might come at the expense of remembering every detail correctly.”
So, if generating false memories goes hand in hand with having a nervous system, does all this leave Brian Williams off the hook?
“It is possible that he conflated the memories,” Chittka said, “depending on his individual vulnerability to witnessing a traumatic event, plus a possible susceptibility to false memories – there is substantial inter-person variation with respect to this. It is equally possible that he was just ‘showing off’ when reporting the incident, and is now resorting to a simple lie to try to escape embarrassment. That is impossible for me to diagnose.”
But if Mr. Williams genuinely did misremember his would-be brush with death, Chittka says he shouldn’t be vilified.
Excerpt from thenextdigit.com
Recently, a new research has been done, which found that the ancient cities were similar to the current modern-day cities in terms of size as well as the density of those settlements. In the research paper, the researcher explains that modern cities with large amount of populations as well as density, are similar to the characteristics of ancient cities. The research claims that the character of the inhabitants of ancient cities is similar to those of inhabitants of modern cities.The study was done by the researchers at Santa Fe Institute and at the University of Colorado Boulder. The main objective of the researchers is to find the functionality of the settlements and they started to find out whether current cities and ancient cities are similar in nature.
Scott Ortman, Researcher at Department of Anthropology, University of Colorado Boulder says,
“Our findings indicate the fundamental processes behind the emergence of scaling in modern cities have structured human settlement organization throughout human history, and that contemporary urban systems are best-conceived as lying on a continuum with the smaller-scale settlement systems known from historical and archaeological research.”
The researcher grouped together and analyzes the structures as well as dimensions of both cities and estimated the way of construction of monuments, housing styles, the amount of people stayed in a region and so on. They found the place or region where the density was high, the productivity was more.
Ortman also said that the results were amazing and unbelievable for them and added that the modern world is radically different from the ancient world with its capitalism, democracy, industrialization and so on. They also noticed that, once the population of a particular area grew, then the productivity of that same place rose high. Even a few patterns that are used in the ancient human societies were same as that we are following in our modern urban system.
“It was amazing and unbelievable,” Ortman said. “We’ve been raised on a steady diet, telling us that, thanks to capitalism, industrialization, and democracy, the modern world is radically different from worlds of the past. What we found here is that the fundamental drivers of robust socioeconomic patterns in modern cities precede all that.”
Excerpt from sciencerecorder.com
| Armed with one of the largest telescopes in the world, the aptly named Very Large Telescope at the ESO Observatory in Chile, astronomers are conducting a search for what they once were certain had to be a brown dwarf star. The only problem is that now the star seems to have vanished without evidence. What happened? Brown dwarfs, compared to their better known red dwarf counterparts are significantly cooler, dimmer objects which at a glance bear more resemblance to planets than to other stars. Although they release heat and bear a chemical composition similar to that of the sun, astronomers tend to refer to them as “failed stars,” since they are too small to set off any thermonuclear reactions within their cores. This particular vanishing dwarf was thought to be part of a double-star system, the V471 Tauri, located within the Taurus constellation, only 163 light years from Earth. Within this system, the stars orbit each other in 12 hour intervals, which causes the brightness to diminish every six hours, when one star crosses directly in front of the other. |
However, the timing of this eclipse never happened at an entirely predictable pace, leading the researchers to suspect that a brown dwarf’s gravitational pull was pushing on the stars and causing the lapse – it’s the only thing consistent with the minimal lapsing patterns. With the use of a new powerful camera called SPHERE, they set out to plot out the location of the brown dwarf, but found nothing where they predicted it would be. “This is how science works,” said Adam Hardy, the study’s lead author who remains undaunted by the road ahead. The new study was published this week by the journal, Astrophysical Journal Letters. “Observations with new technology can either confirm or, as in this case, disprove earlier ideas.” Perhaps most intriguing is that while a brown dwarf appears to be hiding from them, the cluster it waxes influence over is among the brightest and largest of deep-sky objects visible in the evening sky. The binary star system is found in what astronomers call the Hyades cluster, named for the nymphs of Greek mythology who are responsible for the rain. |
Excerpt from seattletimes.com
A decision to list the captive orca Lolita for federal protection is expected to set the stage for a lawsuit from advocates seeking the whale’s release.
By Hal Bernton
Seattle Times staff reporter
The National Oceanic and Atmospheric Administration (NOAA) announced Wednesday the decision to list Lolita as part of the southern resident killer whales of Puget Sound, which already are considered endangered under the federal act.
Whale activists, who petitioned for this status, have long campaigned for Lolita’s return to Puget Sound. They hope the listing will provide a stronger legal case to release Lolita than did a previous lawsuit that centered on alleged violations of the federal Animal Welfare Act.
“This gives leverage under a much stronger law,” said Howard Garrett of the Whidbey Island based Orca Network, which hopes a San Juan Island cove will one day serve as the site for Lolita to re-enter the wild.
NOAA Fisheries officials on Wednesday described their decision in narrow terms, which set no broader precedents. It does not address whether Lolita should be released from the Seaquarium.
“This is a listing decision,” said Will Stelle, the NOAA Fisheries regional administrator for the West Coast. “It is not a decision to free Lolita.”
Aquarium officials have repeatedly said they have no intention of releasing the orca.
“Lolita has been part of the Miami Seaquarium family for 44 years,” said Andrew Hertz, Seaquarium general manager, in a statement.
“Lolita is healthy and thriving in her home where she shares habitat with Pacific white-sided dolphins. There is no scientific evidence that ... Lolita could survive in a sea pen or the open waters of the Pacific Northwest, and we are not willing to treat her life as an experiment.”
Orcas, also known as killer whales, are found in many of the world’s oceans. The southern resident population, which spends several months each year in Puget Sound, is the only group listed in the U.S. under the Endangered Species.
The three pods in the population were reduced by captures by marine parks between 1965 and 1975, NOAA says. Among them was a roundup in Penn Cove where seven whales were captured, including Lolita.
The southern resident pods now number fewer than 80. Possible causes for the decline are reduced prey, pollutants that could cause reproductive problems and oil spills, according to NOAA Fisheries.
Under the Endangered Species Act, it is illegal to cause a “take” of a protected orca, which includes harming or harassing them.
Wednesday, NOAA officials said holding an animal captive, in and of itself, does not constitute a take.
Orca activists are expected to argue in their lawsuit that Lolita's cramped conditions result in a prohibited take.
There is “rising public scorn for the whole idea of performing orcas,” said Garrett, who hopes Seaquarium will decide to release Lolita without a court order.
But NOAA officials still have concerns about releasing captive whales, and any plan to move or release Lolita would require “rigorous scientific review,” the agency said in a statement.
The concerns include the possibility of disease transmission, the ability of a newly released orca to find food and behavior patterns from captivity that could impact wild whales.
NOAA said previous attempts to release captive orcas and dolphins have often been unsuccessful and some have ended in death.
Garrett said the plan for Lolita calls for her to be taken to a netted area of the cove, which could be enlarged later. She would be accompanied by familiar trainers who could “trust and reassure her every bit of the way,” he said.
The controversy over releasing captive whales has been heightened by the experience of Keiko, a captive orca that starred in the 1993 movie “Free Willy,” about a boy who pushed for the release of a whale.
In 1998, Keiko was brought back to his native waters off Iceland to reintroduce him to life in the wild. That effort ended in 2003 when he died in a Norwegian fjord.
Garrett, who visited Keiko in Iceland in 1999, said he was impressed by the reintroduction effort, and that there was plenty of evidence that Keiko was able to catch fish on his own.
“The naysayers predicted that as soon as he got into the (Icelandic) waters he would die, and wild orcas would kill him,” Garrett said. “He proved that 180-degrees wrong. He loved it.”
Mark Simmons, who for two years served as director of animal husbandry for the Keiko-release effort, has a different view. He says Keiko never was able to forage for fish on his own, and that he continued to seek out human contact at every opportunity.
Simmons wrote a book called “Killing Keiko,” that accuses the release effort of leading to a long slow death for the orca, which he says lacked food and then succumbed to an infection.
“It’s not really the fact that Keiko died, but how he died,” Garrett said Wednesday.
 |
University of Maryland computer scientist Yiannis Aloimonos (center) is developing robotic systems able to visually recognize objects and generate new behavior based on those observations. DARPA is funding this research through its Mathematics of Sensing, Exploitation and Execution (MSEE) program. (University of Maryland Photo) |
From darpa.mil
January 29, 2015
DARPA program advances robots’ ability to sense visual information and turn it into action
“The MSEE program initially focused on sensing, which involves perception and understanding of what’s happening in a visual scene, not simply recognizing and identifying objects,” said Reza Ghanadan, program manager in DARPA’s Defense Sciences Offices. “We’ve now taken the next step to execution, where a robot processes visual cues through a manipulation action-grammar module and translates them into actions.”
Another significant advance to come out of the research is the robots’ ability to accumulate and share knowledge with others. Current sensor systems typically view the world anew in each moment, without the ability to apply prior knowledge.
“This system allows robots to continuously build on previous learning—such as types of objects and grasps associated with them—which could have a huge impact on teaching and training,” Ghanadan said. “Instead of the long and expensive process of programming code to teach robots to do tasks, this research opens the potential for robots to learn much faster, at much lower cost and, to the extent they are authorized to do so, share that knowledge with other robots. This learning-based approach is a significant step towards developing technologies that could have benefits in areas such as military repair and logistics.”
The DARPA-funded researchers presented their work today at the 29th meeting of the Association for the Advancement of Artificial Intelligence. The University of Maryland paper is available here: http://ow.ly/I30im
 |
| Various features on a smooth part of the comet's surface in the region named Imhotep. |
Excerpt from wired.com
The Rosetta spacecraft has been studying comet 67P/Churyumov-Gerasimenko up close since August, collecting data of unprecedented detail and taking pictures of a starkly beautiful comet-scape. While the Philae lander has enjoyed much of the spotlight—partly thanks to its now-famous triple landing—Rosetta has been making plenty of its own discoveries.
One of the biggest came last month, when scientists found that the chemical signature of the comet’s water is nothing like that on Earth, contradicting the theory that crashing comets supplied our planet with water. Comet 67P belongs to the Jupiter family of comets, and the findings also imply that these kinds of comets were formed at a wider range of distances from the sun than previously thought, says Michael A’Hearn, a planetary scientist at the University of Maryland, College Park, and member of the Rosetta science team.
Today, scientists have published the first big set of results from Rosetta in a slew of papers in the journal Science. The results include measurements and analyses of the comet’s shape, structure, surface, and the surrounding dust and gas particles. Here are just a few of the amazing things they’ve discovered about Rosetta’s comet so far:
The surface is fantastically weird
The comet has quite the textured landscape, covered with steep cliffs, boulders, weird bumps, cracks, pits, and smooth terrain. There are fractures of all sizes, including one that’s several yards wide and stretches for more than half a mile along the comet’s neck. Researchers don’t yet know what caused these cracks. The pits have steep sides and flat bottoms, ranging in size from a few tens to hundreds of feet wide. Jets of dust shoot out from some of the pits, suggesting that the ejection of material formed these features. Another strange feature is what scientists are calling goosebumps—weird bumpy patches found particularly on steep slopes.
While other features such as pits and fractures range in sizes, all of the goosebumps are about 10 feet wide. No one knows what kind of process would make the bumps, but whatever it is could have played an important part in the comet’s formation. It may be breezy Rosetta spotted dune- and ripple-like patterns,wind tails behind rocks, and even moats surrounding rocks, suggesting that a light breeze may blow dust along the surface. Such a gentle wind would have to come from gases leaking from below.
Because of the extremely low gravity on the comet, it wouldn’t take a strong gust to blow things around. It may have formed from two separate pieces Or not. The most distinct feature of comet 67P is its odd, two-lobed shape, which resembles a duck. Although scientists have seen this lobed structure in other comets before, namely Borrelly and Hartley 2, none are as pronounced as comet 67P’s. Borrelly and Hartley 2 look more like elongated potatoes while 67P has a clearly defined head and body. The strange shape suggests the comet was once two separate pieces called cometesimals—what are now the duck’s head and body—that stuck together.
The other possibility is that erosion ate away the parts around the neck. Preliminary evidence points to the first hypothesis.
“Probably most of us on the OSIRIS team lean toward thinking it was two cometesimals,” A’Hearn said. (OSIRIS is one of Rosetta’s imaging instruments.) But the scientists won’t have conclusive evidence until they study the comet in more detail. For example, they now see layering along the neck—if erosion carved out the comet’s duck shape, they should find the same same layering pattern continuing onto the other side of the neck.
Black, with a tinge of red
Even Rosetta’s color pictures show a grayish comet, but if you were to see it in person, you would see a pitch-black chunk of dust and ice, as it reflects only six percent of incoming light. By comparison, the moon reflects 12 percent of incoming light and Earth reflects 31 percent. But comet 67P’s not completely black, as it has a hint of red. Water, water, nowhere? The comet’s covered in opaque, organic compounds. Although comet 67P is undoubtedly icy, it hardly shows any water ice on its surface at all.
Which isn’t too surprising, as comets Tempel 1 and Hartley 2 didn’t have much ice on their surfaces either, A’Hearn says. Rosetta has yet to see sunlight reach every side of the comet yet, so there may still be some icy patches hidden from view. But, researchers do see the comet spraying water vapor into space, which means water ice likely lies just beneath the surface. The ice doesn’t have to be more than a centimeter deep to be invisible from the infrared instruments that detect the ice. Indeed, the data from Philae’s first bounce suggested that there’s a hard layer of ice beneath 4 to 8 inches of dust.
This duck floats
If you could find a big enough pond, that is. Like other known comets, the density of comet 67P is about half that of water ice. Initial measurements reveal that it’s also very porous—as much as 80 percent of it may be empty space. Rosetta has found depressions, which may have formed when the surface collapsed over particularly porous material underneath.
Different from every angle
As the comet nears the sun, it heats up, and ices and other volatile chemicals sublimate, spraying gases into space. So far, the most prominent gases that have been ejected are water vapor, carbon dioxide, and carbon monoxide. They spew out in different amounts from different parts of the comet. In particular, a lot of the water has been observed gushing out from the neck.The comet will continue to get more active as it reaches its closest approach to the sun in mid-August. It will burst with stronger jets of gas and dust, and maybe even blast off chunks of itself. If the comet is this interesting now, A’Hearn says, just wait until it gets to its nearest point to the sun, when it’s just 1.29 times farther from the sun than Earth is.
Excerpt from
csmonitor.com
Vikings may have been family men who traveled with their wives to new lands, according to a new study of ancient Viking DNA.
Maternal DNA from ancient Norsemen closely matches that of modern-day people in the North Atlantic isles, particularly from the Orkney and Shetland Islands.
The findings suggest that both Viking men and women sailed on the ships to colonize new lands. The new study also challenges the popular conception of Vikings as glorified hoodlums with impressive seafaring skills.
"It overthrows this 19th century idea that the Vikings were just raiders and pillagers," said study co-author Erika Hagelberg, an evolutionary biologist at the University of Oslo in Norway. "They established settlements and grew crops, and trade was very, very important."
Vikings hold a special place in folklore as manly warriors who terrorized the coasts of France, England and Germany for three centuries. But the Vikings were much more than pirates and pillagers. They established far-flung trade routes, reached the shores of present-day America, settled in new lands and even founded the modern city of Dublin, which was called Dyfflin by the Vikings.
Some earlier genetic studies have suggested that Viking males traveled alone and then brought local women along when they settled in a new location. For instance, a 2001 study published in the American Journal of Human Genetics suggested that Norse men brought Gaelic women over when they colonized Iceland.
Modern roots
To learn more about Norse colonization patterns, Hagelberg and her colleagues extracted teeth and shaved off small wedges of long bones from 45 Norse skeletons that were dated to between A.D. 796 and A.D. 1066. The skeletons were first unearthed in various locations around Norway and are now housed in the Schreiner Collection at the University of Oslo.The team looked at DNA carried in the mitochondria, the energy powerhouses of the cell. Because mitochondria are housed in the cytoplasm of a woman's egg, they are passed on from a woman to her children and can therefore reveal maternal lineage. The team compared that material with mitochondrial DNA from 5,191 people from across Europe, as well as with previously analyzed samples from 68 ancient Icelanders.
The ancient Norse and Icelandic genetic material closely matched the maternal DNA in modern North Atlantic people, such as Swedes, Scots and the English. But the ancient Norse seemed most closely related to people from Orkney and Shetland Islands, Scottish isles that are quite close to Scandinavia.
Mixed group
"It looks like women were a more significant part of the colonization process compared to what was believed earlier," said Jan Bill, an archaeologist and the curator of the Viking burial ship collection at the Museum of Cultural History, a part of the University of Oslo.That lines up with historical documents, which suggest that Norse men, women and children — but also Scottish, British and Irish families — colonized far-flung islands such as Iceland, Bill told Live Science. Bill was not involved with the new study.
"This picture that we have of Viking raiding — a band of long ships plundering — there obviously would not be families on that kind of ship," Bill said. "But when these raiding activities started to become a more permanent thing, then at some point you may actually see families are traveling along and staying in the camps."
As a follow-up, the team would like to compare ancient Norse DNA to ancient DNA from Britain, Scotland and the North Atlantic Isles, to get a better look at exactly how all these people are related, Hagelberg said.
The findings were published today (Dec. 7) in the journal Philosophical Transactions of the Royal Society B.
How will the world end? From ‘demonic’ AI to nuclear war — seven scenarios that could end human race
news.nationalpost.com
Humanity may have already created its own nemesis, Professor Stephen Hawking warned last week. The Cambridge University physicist claimed that new developments in the field of artificial intelligence (AI) mean that within a few decades, computers thousands of times more powerful than in existence today may decide to usurp their creators and effectively end humanity’s 100,000-year dominance of Earth.
This Terminator scenario is taken seriously by many scientists and technologists. Before Prof. Hawking made his remarks, Elon Musk, the genius behind the Tesla electric car and PayPal, had stated that “with artificial intelligence, we are summoning the demon,” comparing it unfavourably with nuclear war as the most potent threat to humanity’s existence.
Aside from the rise of the machines, many potential threats have been identified to our species, our civilization, even our planet. To keep you awake at night, here are seven of the most plausible.
1. ASTEROID STRIKE
Our solar system is littered with billions of pieces of debris, from the size of large boulders to objects hundreds of kilometres across. We know that, from time to time, these hit the Earth. Sixty-five-million years ago, an object – possibly a comet a few times larger than the one on which the Philae probe landed last month – hit the Mexican coast and triggered a global winter that wiped out the dinosaurs. In 1908, a smaller object hit a remote part of Siberia and devastated hundreds of square kilometres of forest. Last week, 100 scientists, including Lord Rees of Ludlow, the Astronomer Royal, called for the creation of a global warning system to alert us if a killer rock is on the way.
Probability: remote in our lifetime, but one day we will be hit.
Result: there has been no strike big enough to wipe out all life on Earth – an “extinction-level event” – for at least three billion years. But a dino-killer would certainly be the end of our civilization and possibly our species.
2. ARTIFICIAL INTELLIGENCE
Prof. Hawking is not worried about armies of autonomous drones taking over the world, but something more subtle – and more sinister. Some technologists believe that an event they call the Singularity is only a few decades away. This is a point at which the combined networked computing power of the world’s AI systems begins a massive, runaway increase in capability – an explosion in machine intelligence. By then, we will probably have handed over control to most of our vital systems, from food distribution networks to power plants, sewage and water treatment works, and the global banking system. The machines could bring us to our knees without a shot being fired. And we cannot simply pull the plug, because they control the power supplies.
Probability: unknown, although computing power is doubling every 18 months. We do not know if machines can be conscious or “want” to do anything, and sceptics point out that the cleverest computers in existence are currently no brighter than cockroaches.
Result: if the web wakes up and wants to sweep us aside, we may have a fight on our hands (perhaps even something similar to the man vs. machines battle in the Terminator films). But it is unlikely that the machines will want to destroy the planet – they “live” here, too.
3. A GENETICALLY CREATED PLAGUE
This is possibly the most terrifying short-term threat because it is so plausible. The reason Ebola has not become a worldwide plague – and will not do so – is because it is so hard to transmit, and because it incapacitates and kills its victims so quickly. However, a modified version of the disease that can be transmitted through the air, or which allows its host to travel around for weeks, symptom-free, could kill many millions. It is unknown whether any terror group has the knowledge or facilities to do something like this, but it is chilling to realize that the main reason we understand Ebola so well is that its potential to be weaponized was quickly realized by defence experts.
Probability: someone will probably try it one day.
Result: potentially catastrophic. “Ordinary” infectious diseases such as avian-flu strains have the capability to wipe out hundreds of millions of people.
4. NUCLEAR WAR
This is still the most plausible “doomsday” scenario. Despite arms-limitations treaties, there are more than 15,000 nuclear warheads and bombs in existence – many more, in theory, than would be required to kill every human on Earth. Even a small nuclear war has the potential to cause widespread devastation. In 2011, a study by NASA scientists concluded that a limited atomic war between India and Pakistan involving just 100 Hiroshima-sized detonations would throw enough dust into the air to cause temperatures to drop more than 1.2C globally for a decade.
Probability: high. Nine states have nuclear weapons, and more want to join the club. The nuclear wannabes are not paragons of democracy.
Result: it is unlikely that even a global nuclear war between Russia and NATO would wipe us all out, but it would kill billions and wreck the world economy for a century. A regional war, we now know, could have effects far beyond the borders of the conflict.
5. PARTICLE ACCELERATOR DISASTER
Before the Large Hadron Collider (LHC), the massive machine at CERN in Switzerland that detected the Higgs boson a couple of years ago, was switched on, there was a legal challenge from a German scientist called Otto Rossler, who claimed the atom-smasher could theoretically create a small black hole by mistake – which would then go on to eat the Earth.
The claim was absurd: the collisions in the LHC are far less energetic than those caused naturally by cosmic rays hitting the planet. But it is possible that, one day, a souped-up version of the LHC could create something that destroys the Earth – or even the universe – at the speed of light.
Probability: very low indeed.
Result: potentially devastating, but don’t bother cancelling the house insurance just yet.
6. ‘GOD’ REACHES FOR THE OFF-SWITCH
Many scientists have pointed out that there is something fishy about our universe. The physical constants – the numbers governing the fundamental forces and masses of nature – seem fine-tuned to allow life of some form to exist. The great physicist Sir Fred Hoyle once wondered if the universe might be a “put-up job”.
More recently, the Oxford University philosopher Nick Bostrom has speculated that our universe may be one of countless “simulations” running in some alien computer, much like a computer game. If so, we have to hope that the beings behind our fake universe are benign – and do not reach for the off-button should we start misbehaving.
Probability: according to Professor Bostrom’s calculations, if certain assumptions are made, there is a greater than 50% chance that our universe is not real. And the increasingly puzzling absence of any evidence of alien life may be indirect evidence that the universe is not what it seems.
Result: catastrophic, if the gamers turn against us. The only consolation is the knowledge that there is absolutely nothing we can do about it.
7. CLIMATE CATASTROPHE
Almost no serious scientists now doubt that human carbon emissions are having an effect on the planet’s climate. The latest report by the Intergovernmental Panel on Climate Change suggested that containing temperature rises to below 2C above the pre-industrial average is now unlikely, and that we face a future three or four degrees warmer than today.
This will not literally be the end of the world – but humanity will need all the resources at its disposal to cope with such a dramatic shift. Unfortunately, the effects of climate change will really start to kick in just at the point when the human population is expected to peak – at about nine billion by the middle of this century. Millions of people, mostly poor, face losing their homes to sea-level rises (by up to a metre or more by 2100) and shifting weather patterns may disrupt agriculture dramatically.
Probability: it is now almost certain that CO2 levels will keep rising to 600 parts per billion and beyond. It is equally certain that the climate will respond accordingly.
Result: catastrophic in some places, less so in others (including northern Europe, where temperature rises will be moderated by the Atlantic). The good news is that, unlike with most of the disasters here, we have a chance to do something about climate change now.
Humanity may have already created its own nemesis, Professor Stephen Hawking warned last week. The Cambridge University physicist claimed that new developments in the field of artificial intelligence (AI) mean that within a few decades, computers thousands of times more powerful than in existence today may decide to usurp their creators and effectively end humanity’s 100,000-year dominance of Earth.
This Terminator scenario is taken seriously by many scientists and technologists. Before Prof. Hawking made his remarks, Elon Musk, the genius behind the Tesla electric car and PayPal, had stated that “with artificial intelligence, we are summoning the demon,” comparing it unfavourably with nuclear war as the most potent threat to humanity’s existence.
Aside from the rise of the machines, many potential threats have been identified to our species, our civilization, even our planet. To keep you awake at night, here are seven of the most plausible.
Getty Images / ThinkStockAn artist's depiction of an asteroid approaching Earth.
Our solar system is littered with billions of pieces of debris, from the size of large boulders to objects hundreds of kilometres across. We know that, from time to time, these hit the Earth. Sixty-five-million years ago, an object – possibly a comet a few times larger than the one on which the Philae probe landed last month – hit the Mexican coast and triggered a global winter that wiped out the dinosaurs. In 1908, a smaller object hit a remote part of Siberia and devastated hundreds of square kilometres of forest. Last week, 100 scientists, including Lord Rees of Ludlow, the Astronomer Royal, called for the creation of a global warning system to alert us if a killer rock is on the way.
Probability: remote in our lifetime, but one day we will be hit.
Result: there has been no strike big enough to wipe out all life on Earth – an “extinction-level event” – for at least three billion years. But a dino-killer would certainly be the end of our civilization and possibly our species.
Warner Bros.When artificial intelligence becomes self-aware, there is a chance it will look something like this scene from Terminator 3.
Prof. Hawking is not worried about armies of autonomous drones taking over the world, but something more subtle – and more sinister. Some technologists believe that an event they call the Singularity is only a few decades away. This is a point at which the combined networked computing power of the world’s AI systems begins a massive, runaway increase in capability – an explosion in machine intelligence. By then, we will probably have handed over control to most of our vital systems, from food distribution networks to power plants, sewage and water treatment works, and the global banking system. The machines could bring us to our knees without a shot being fired. And we cannot simply pull the plug, because they control the power supplies.
Result: if the web wakes up and wants to sweep us aside, we may have a fight on our hands (perhaps even something similar to the man vs. machines battle in the Terminator films). But it is unlikely that the machines will want to destroy the planet – they “live” here, too.
Handout/AFP/Getty ImagesLaboratory technicians and physicians work on samples during research on the evolving Ebola disease in bats, at the Center for Emerging and Zoonotic Diseases research Laboratory of the National Institute for Communicable Diseases in Pretoria on Nov. 21, 2011.
This is possibly the most terrifying short-term threat because it is so plausible. The reason Ebola has not become a worldwide plague – and will not do so – is because it is so hard to transmit, and because it incapacitates and kills its victims so quickly. However, a modified version of the disease that can be transmitted through the air, or which allows its host to travel around for weeks, symptom-free, could kill many millions. It is unknown whether any terror group has the knowledge or facilities to do something like this, but it is chilling to realize that the main reason we understand Ebola so well is that its potential to be weaponized was quickly realized by defence experts.
Probability: someone will probably try it one day.
Result: potentially catastrophic. “Ordinary” infectious diseases such as avian-flu strains have the capability to wipe out hundreds of millions of people.
AP Photo/U.S. Army via Hiroshima Peace Memorial MuseumA mushroom cloud billows about one hour after a nuclear bomb was detonated above Hiroshima, Japan Aug. 6, 1945.
This is still the most plausible “doomsday” scenario. Despite arms-limitations treaties, there are more than 15,000 nuclear warheads and bombs in existence – many more, in theory, than would be required to kill every human on Earth. Even a small nuclear war has the potential to cause widespread devastation. In 2011, a study by NASA scientists concluded that a limited atomic war between India and Pakistan involving just 100 Hiroshima-sized detonations would throw enough dust into the air to cause temperatures to drop more than 1.2C globally for a decade.
Probability: high. Nine states have nuclear weapons, and more want to join the club. The nuclear wannabes are not paragons of democracy.
Result: it is unlikely that even a global nuclear war between Russia and NATO would wipe us all out, but it would kill billions and wreck the world economy for a century. A regional war, we now know, could have effects far beyond the borders of the conflict.
CERN)/MCTThis is one of the huge particle detectors in the Large Hadron Collider, a 17 mile-long tunnel under the French-Swiss border. Scientists are searching for evidence of what happened right after- and perhaps before- the Big Bang.
Before the Large Hadron Collider (LHC), the massive machine at CERN in Switzerland that detected the Higgs boson a couple of years ago, was switched on, there was a legal challenge from a German scientist called Otto Rossler, who claimed the atom-smasher could theoretically create a small black hole by mistake – which would then go on to eat the Earth.
The claim was absurd: the collisions in the LHC are far less energetic than those caused naturally by cosmic rays hitting the planet. But it is possible that, one day, a souped-up version of the LHC could create something that destroys the Earth – or even the universe – at the speed of light.
Probability: very low indeed.
Result: potentially devastating, but don’t bother cancelling the house insurance just yet.
AP Photo/Oculus Rift/FoxThis photo shows a scene fromX-Men: Days of Future Past virtual reality experience. Oxford University philosopher Nick Bostrom has speculated that our universe may be one of countless "simulations" running in some alien computer, much like a computer game.
Many scientists have pointed out that there is something fishy about our universe. The physical constants – the numbers governing the fundamental forces and masses of nature – seem fine-tuned to allow life of some form to exist. The great physicist Sir Fred Hoyle once wondered if the universe might be a “put-up job”.
More recently, the Oxford University philosopher Nick Bostrom has speculated that our universe may be one of countless “simulations” running in some alien computer, much like a computer game. If so, we have to hope that the beings behind our fake universe are benign – and do not reach for the off-button should we start misbehaving.
Probability: according to Professor Bostrom’s calculations, if certain assumptions are made, there is a greater than 50% chance that our universe is not real. And the increasingly puzzling absence of any evidence of alien life may be indirect evidence that the universe is not what it seems.
Result: catastrophic, if the gamers turn against us. The only consolation is the knowledge that there is absolutely nothing we can do about it.
AP Photo/Charles Rex ArbogastFloodwaters from the Souris River surround homes near Minot State University in Minot, N.D. on June 27, 2011. Global warming is rapidly turning America the beautiful into America the stormy and dangerous, according to the National Climate Assessment report released Tuesday, May 6, 2014.
Almost no serious scientists now doubt that human carbon emissions are having an effect on the planet’s climate. The latest report by the Intergovernmental Panel on Climate Change suggested that containing temperature rises to below 2C above the pre-industrial average is now unlikely, and that we face a future three or four degrees warmer than today.
This will not literally be the end of the world – but humanity will need all the resources at its disposal to cope with such a dramatic shift. Unfortunately, the effects of climate change will really start to kick in just at the point when the human population is expected to peak – at about nine billion by the middle of this century. Millions of people, mostly poor, face losing their homes to sea-level rises (by up to a metre or more by 2100) and shifting weather patterns may disrupt agriculture dramatically.
Probability: it is now almost certain that CO2 levels will keep rising to 600 parts per billion and beyond. It is equally certain that the climate will respond accordingly.
Result: catastrophic in some places, less so in others (including northern Europe, where temperature rises will be moderated by the Atlantic). The good news is that, unlike with most of the disasters here, we have a chance to do something about climate change now.
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bbc.com
Artist Carrie Paterson has long dreamed of beaming messages far out to the emptiness of space. Except her messages would have an extra dimension – smell.
By broadcasting formulae of aromatic chemicals, she says, aliens could reconstruct all sorts of whiffs that help to define life on Earth: animal blood and faeces, sweet floral and citrus scents or benzene to show our global dependence on the car. This way intelligent life forms on distant planets who may not see or hear as we do, says Paterson, could explore us through smell, one of the most primitive and ubiquitous senses of all.
It is nearly 40 years since the Arecibo facility sent messages out into space (Wikipedia)
Her idea is only the latest in a list of attempts to hail intelligent life outside of the Solar System. Forty years ago this month, the Arecibo radio telescope in Puerto Rico sent an iconic picture message into space – and we’ve arguably been broadcasting to aliens ever since we invented TV and radio.
However in recent years, astronomers, artists, linguists and anthropologists have been converging on the idea that creating comprehensible messages for aliens is much harder than it seems. This week, Paterson and others discussed the difficulties of talking to our cosmic neighbours at a conference called Communicating Across the Cosmos, held by Seti (Search for Extraterrestrial Intelligence). It seems our traditional ways of communicating through pictures and language may well be unintelligible – or worse, be catastrophically misconstrued. So how should we be talking to ET?
Lost in translation?
We have always wanted to send messages about humanity beyond the planet. According to Albert Harrison, a space psychologist and author of Starstruck: Cosmic Visions in Science, Religion and Folklore, the first serious designs for contacting alien life appeared two centuries ago, though they never got off the ground.
In the 1800s, mathematician Carl Gauss proposed cutting down lines of trees in a densely forested area and replanting the strips with wheat or rye, Harrison wrote in his book. “The contrasting colours would form a giant triangle and three squares known as a Pythagoras figure which could be seen from the Moon or even Mars.” Not long after, the astronomer Joseph von Littrow proposed creating huge water-filled channels topped with kerosene. “Igniting them at night showed geometric patterns such as triangles that Martians would interpret as a sign of intelligence, not nature.”
But in the 20th Century, we began to broadcast in earnest. The message sent by Arecibo hoped to make first contact on its 21,000 year journey to the edge of the Milky Way. The sketches it contained, made from just 1,679 digital bits, look cute to us today, very much of the ‘Pong’ video game generation. Just before then, Nasa’s Pioneer 10 and 11 space probes each carried a metal calling card bolted onto their frame with symbols and drawings on the plaque, showing a naked man and woman.
Yet it’s possible that these kinds of message may turn out to be incomprehensible to aliens; they might find it as cryptic as we find Stone Age etchings.
Antique tech
“Linear drawings of a male and a female homo sapiens are legible to contemporary humans,” says Marek Kultys, a London-based science communications designer. ”But the interceptors of Pioneer 10 could well assume we are made of several separate body parts (i.e. faces, hair and the man’s chest drawn as a separate closed shapes) and our body surface is home for long worm-like beings (the single lines defining knees, abdomens or collarbones.).”
Man-made tech may also be an issue. The most basic requirement for understanding Voyager’s Golden Record, launched 35 years ago and now way out beyond Pluto, is a record player. Aliens able to play it at 16 and 2/3 revolutions a minute will hear audio greetings in 55 world languages, including a message of ‘Peace and Friendship’ from former United Nations Secretary General Kurt Waldheim. But how many Earthlings today have record players, let alone extraterrestrials?
Our sights and sounds of Earth might be unintelligible to an alien audience (Nasa)
Time capsule
Inevitably such messages become outdated too, like time capsules. Consider the case of the Oglethorpe Atlanta Crypt of Civilization – a time capsule sealed on Earth in 1940, complete with a dry martini and a poster of Gone With the Wind. It was intended as a snapshot of 20th Century life for future humans, not aliens, but like an intergalactic message, may only give a limited picture to future generations. When, in 61,000 years, the Oglethorpe time capsule is opened, would Gone With The Wind have stood the test of time?
This message was taken into the stars by Pioneer - but we have no idea if aliens would be able to understand it (Nasa)
Kultys argues that all these factors should be taken into account when we calculate the likelihood of communicating with intelligent life. The astronomer Frank Drake’s famous equation allows anyone to calculate how many alien species are, based on likely values of seven different factors. At a UK Royal Society meeting in 2010 Drake estimated there are roughly 10,000 detectable civilisations in the galaxy. Yet Kultys points out that we should also factor in how many aliens are using the same channel of communications as us, are as willing to contact us as we are them, whose language we hope to learn, and who are physically similar to us.
Another barrier we might consider is the long distance nature of trans-cosmos communication. It means that many years ‒ even a thousand ‒ could pass between sending a message and receiving a reply. Paterson sees romance in that. “Our hope for communication with another intelligent civilisation has a melancholic aspect to it.
We are on an island in a vast, dark space. Imagine if communication… became like an exchange of perfumed love letters with the quiet agony of expectation... Will we meet? Will we be as the other imagined? Will the other be able to understand us?”
Ready for an answer?
Anthropologist John Traphagan of the University of Texas in Austin has been asking the same question, though his view is more cautious. "When it comes to ET, you'll get a signal of some kind; not much information and very long periods between ‘Hi, how are you?’ and whatever comes back. We may just shrug our shoulders and say 'This is boring’, and soon forget about it or, if the time lag wasn't too long, we might use the minimal information we get from our slow-speed conversation to invent what we think they're like and invent a kind concept of what they're after.”
The aliens in Independence Day (1996) did not come in peace (20th Century Fox)
Consider how easy it is to mess up human-to-human communications; I got Traphagan’s first name wrong when I e-mailed him for this article. An apology within minutes cleared up the confusion, yet if he had been an alien anthropologist on some distant planet it would have taken much longer to fix. He later confessed: "I could have thought this is a snooty English journalist and our conversation might never have happened."
Even if Earth’s interstellar messaging committees weeded out the typos, cultural gaffes are always a possibility. These can only be avoided by understanding the alien’s culture – something that’s not easy to do, especially when you’ve never met those you’re communicating with.
Rosy picture
So, what is the best way to communicate? This is still up for grabs – perhaps it’s via smell, or some other technique we haven’t discovered yet. Clearly, creating a message that is timeless, free of cultural bias and universally comprehensible would be no mean feat.
But for starters, being honest about who we are is important if we want to have an extra-terrestrial dialogue lasting centuries, says Douglas Vakoch, director of interstellar message composition at Seti. (Otherwise, intelligent civilisations who’ve decoded our radio and TV signals might smell a rat.)
The golden discs aboard the Voyager spacecraft require aliens to understand how to play a record (Nasa)
“Let's not try to hide our shortcomings,” says Vakoch. “The message we should send to another world is straightforward: We are a young civilisation, in the throes of our technological adolescence. We're facing a lot of problems here on Earth, and we're not even sure that we'll be around as a species when their reply comes in. But in spite of all of these challenges, we humans also have hope – especially hope in ourselves."
Yet ultimately what matters, says Paterson, is that they stop and consider the beings who sent them a message; the people who wanted to say: “Here are some important things. Here’s our DNA, here is some maths and universal physics. And here is our longing and desire to say “I’m like you, but I’m different.”
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Stardust got in their eyes.
In the spring a group of astronomers who go by the name of Bicep announced that they had detected ripples in the sky, gravitational waves that were the opening notes of the Big Bang. The finding was heralded as potentially the greatest discovery of the admittedly young century, but some outside astronomers said the group had underestimated the extent to which interstellar dust could have contaminated the results — a possibility that the group conceded in its official report in June.
Now a long-awaited report by astronomers using data from the European Space Agency’s Planck satellite has confirmed that criticism, concluding that there was enough dust in Bicep’s view of the sky to produce the swirly patterns without recourse to primordial gravitational waves.
“We show that even in the faintest dust-emitting regions there are no ‘clean’ windows in the sky,” the Planck collaboration, led by Jean-Loup Puget of the Astrophysical Institute in Paris, wrote in a paper submitted to the journal Astronomy & Astrophysics and posted online Monday.
As a result, cosmologists like the Bicep crew cannot ignore dust in their calculations. “However,” said Jonathan Aumont, another of the Planck authors, also from the Paris institute, “our work does not imply that they did not measure at all a cosmological signal.
Moreover, due to the very different observation techniques and signal processing in the Bicep2 and Planck experiments, we cannot say how much of the signal they measured is due to dust” and how much to gravitational waves.
So this is not the end of the story, both the Planck scientists and the Bicep group agree. But the original euphoria that the secrets of inflation and quantum gravity might be at hand has evaporated. Planck and Bicep are now collaborating on a detailed comparison of their results.
John M. Kovac of the Harvard-Smithsonian Center for Astrophysics, lead author of the Bicep paper, said the new report confirmed in greater detail the trend suggested by the first Planck papers in the spring, which indicated there is more dust even in the cleanest parts of the galaxy than anyone had thought.
Raphael Flauger of the Institute for Advanced Study in Princeton, N. J., who first raised the issue of dust in the Bicep report, said it confirmed what he had thought. “It doesn’t leave a lot of wiggle room,” he wrote in an email, “and it seems clear that at least the majority of the signal is caused by dust.”
The gravitational waves may exist, although they would be weaker than the Bicep analysis indicated, causing theorists to reshuffle their ideas. As Richard Bond, an early universe expert at the University of Toronto and a Planck team member, put it: “Planck showed that dust could possibly be the entire Bicep2 signal, but Planck alone cannot decide. We have to do this in combination with Bicep2.”
The joint comparison and Planck’s own polarization maps are due at the end of the year.
If true, Bicep’s detection of gravitational waves would confirm a theory that the universe began with a violent outward antigravitational swoosh known as inflation, the mainspring of Big Bang theorizing for the last three decades.
The disagreement over the Bicep finding will not mean the end of inflation theory; it just means it will be harder for cosmologists to find out how it worked. The Bicep group and an alphabet soup of competitors are soldiering on with new telescopes and experiments aimed at peeling away the secrets of the sky.
Michael S. Turner, a cosmologist at the University of Chicago, said: “This is going to be a long march, but the goal of probing the earliest moments of the universe makes it well worth the effort. Dust is the bane of the existence of astrophysicists — and cosmologists. It is everywhere, and yet our understanding of it is very poor.”
Others are less optimistic. Paul J. Steinhardt of Princeton University, a critic of the Bicep paper — and of inflation theory — said in an email that the Bicep paper should be retracted, “and we should return to good scientific practice.”
The Bicep observations are the deepest look yet into a thin haze of microwaves, known as cosmic background radiation, left over from end of the Big Bang, when the cosmos was about 380,000 years old.
According to theory, the onset of inflation, less than a trillionth of a second after time began, should have left ripples in space-time known as gravitational waves. They would manifest as corkscrew patterns in the direction of polarization of the cosmic microwaves.
The Bicep group — its name is an acronym for Background Imaging of Cosmic Extragalactic Polarization — is led by Dr. Kovac; Jamie Bock of Caltech; Clement Pryke of the University of Minnesota; and Chao-Lin Kuo of Stanford. They have deployed a series of radio telescopes at the South Pole in search of the swirl pattern. Their most recent, Bicep2, detected a signal in the sweet spot for some of the most popular models of inflation, leading to a splashy news conference and a summer of controversy and gossip.
As the critics pointed out, things besides quantum ripples from the beginning of time could produce those swirls, including light from interstellar dust polarized by magnetic fields in space.
Planck, launched in 2008 to survey the cosmic microwave sky, can distinguish the characteristic signature of dust by comparing the sky brightness in several radio frequencies, as well as measuring its direction of polarization. Bicep2, in contrast, looked at only one frequency, 150 gigahertz.
The Bicep astronomers asked for Planck data on their patch of sky, but it was not available until now because of suspected instrument problems, Dr. Aumont said. So they extrapolated from existing data to conclude that there was little dust interfering with their observations.
The new Planck report has knocked the pins out from under that. But there are still large uncertainties that leave room for primordial gravitational waves at some level. For example, the Planck team had to extrapolate some of its own measurements.
As the Planck report says, “This result emphasizes the need for a dedicated joint Planck-Bicep2 analysis.”
The group hopes this analysis will include data from the latest Bicep telescope, called the Keck Array, which has been gathering data for several months. In an interview this summer, Dr. Kovac said, “It’s been a funny year to be in the spotlight like this.” He said the group stood behind its work, even if the ultimate interpretation of the measurements is up for grabs.
Acknowledging that dust would not be as sexy a discovery as ripples from inflation, Dr. Kovac said, “It’s really important as an experimentalist that you can divorce yourself from an investment in what the answer is.”
He went on: “One thing that would distress me bitterly is if a major mistake in the measurement or of the analysis would come to light. The most pressing question is, what are the dust contributions to the signal?”
Stay tuned.
Lyman Page, an astrophysicist at Princeton, said the episode illustrated the messy progress of science.
“Taking a step back,” he said by email, “it is amazing that a precise measurement of the cosmos can be made, discussed in fullness, and refuted by another measurement in such a short amount of time. It is testament to a healthy field.”
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