Tag: difficult (page 4 of 17)

What Would It Be Like to Live on Mercury?

February 24, 2015 / / 0 Comments


Mercury With Subtle Colors
Mercury's extreme temperatures and lack of an atmosphere would make it very difficult, if not impossible, for people to live on the planet. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington


Excerpt from  space.com
By Joseph Castro, Space.com Contributor


Have you ever wondered what it might be like to homestead on Mars or walk on the moons of Saturn? So did we. This is the first in Space.com's 12-part series on what it might be like to live on or near planets in our solar system, and beyond. Check back each week for the next space destination.
With its extreme temperature fluctuations, Mercury is not likely a planet that humans would ever want to colonize. But if we had the technology to survive on the planet closest to the sun, what would it be like to live there?

To date, only two spacecraft have visited Mercury. The first, Mariner 10, conducted a series of Mercury flybys in 1974, but the spacecraft only saw the lit half of the planet. NASA's MESSENGER spacecraft, on the other hand, conducted flybys and then entered Mercury's orbit — in March of 2013, images from the spacecraft allowed scientists to completely map the planet for the first time.



MESSENGER photos of Mercury show that the planet has water ice at its poles, which sit in permanent darkness. Mining this ice would be a good way to live off the land, but setting up bases at the poles might not be a good idea, said David Blewett, a participating scientist with the Messenger program.

"The polar regions would give you some respite from the strength of the sun on Mercury," Blewett told Space.com. "But, of course, it's really cold in those permanently shadowed areas where the ice is, and that presents its own challenge."

A better option, he said, would probably be to set up a home base not far from one of the ice caps, perhaps on a crater rim, and have a water mining operation at the pole.

Still, dealing with extreme temperatures on Mercury would likely be unavoidable: Daytime temperatures on the planet can reach 800 degrees Fahrenheit (430 degrees Celsius), while nighttime temperatures can drop down to minus 290 degrees Fahrenheit (minus 180 degrees Celsius).

Scientists once believed Mercury was tidally locked with the sun, meaning that one side of the planet always faces the sun because it takes the same amount of time to rotate around its axis as it does to revolve around the star. But we now know that Mercury's day lasts almost 59 Earth days and its year stretches for about 88 Earth days.

Interestingly, the sun has an odd path through the planet's sky over the course of Mercury's long day, because of the interaction between Mercury's spin rate and its highly elliptical orbit around the sun.

"It [the sun] rises in the east and moves across the sky, and then it pauses and moves backwards just a tad. It then resumes its motion towards the west and sunset," said Blewett, adding that the sun appears 2.5 times larger in Mercury's sky than it does in Earth's sky.

And during the day, Mercury's sky would appear black, not blue, because the planet has virtually no atmosphere to scatter the sun's light. "Here on Earth at sea level, the molecules of air are colliding billions of times per second," Blewett said. "But on Mercury, the atmosphere, or 'exosphere,' is so very rarefied that the atoms essentially never collide with other exosphere atoms." This lack of atmosphere also means that the stars wouldn't twinkle at night.



Without an atmosphere, Mercury doesn't have any weather; so while living on the planet, you wouldn't have to worry about devastating storms. And since the planet has no bodies of liquid water or active volcanoes, you'd be safe from tsunamis and eruptions.

But Mercury isn't devoid of natural disasters. "The surface is exposed to impacts of all sizes," Blewett said. It also may suffer from earthquakes due to compressive forces that are shrinking the planet (unlike Earth, Mercury doesn't have tectonic activity).

Mercury is about two-fifths the size of Earth, with a similar gravity to Mars, or about 38 percent of Earth's gravity. This means that you could jump three times as high on Mercury, and heavy objects would be easier to pick up, Blewett said. However, everything would still have the same mass and inertia, so you could be knocked over if someone threw a heavy object at you, he added.

Finally, you can forget about a smooth Skype call home: It takes at least 5 minutes for signals from Mercury to reach Earth, and vice versa.

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Mysterious Galaxy X Found Finally? Dark Matter Hunters Would Like To Believe So

February 17, 2015 / / 0 Comments

Excerpt from techtimes.comAstronomers have long suspected strange ripples in hydrogen gas in the disk of our Milky Way galaxy are caused by the gravity of an unseen dwarf galaxy dominated by dark matter -- and now they think they've found this "Gal...

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Ancient rocks show life could have flourished on Earth 3.2 billion years ago

February 17, 2015 / / 0 Comments


photo of red rocks and blue sky
The oldest samples are sedimentary rocks that formed 3.2 billion years ago in
northwestern Australia. They contain chemical evidence for nitrogen
fixation by microbes.R. Buick / UW



Excerpt from
washington.edu

A spark from a lightning bolt, interstellar dust, or a subsea volcano could have triggered the very first life on Earth.
But what happened next? Life can exist without oxygen, but without plentiful nitrogen to build genes – essential to viruses, bacteria and all other organisms – life on the early Earth would have been scarce.

The ability to use atmospheric nitrogen to support more widespread life was thought to have appeared roughly 2 billion years ago. Now research from the University of Washington looking at some of the planet’s oldest rocks finds evidence that 3.2 billion years ago, life was already pulling nitrogen out of the air and converting it into a form that could support larger communities.

“People always had the idea that the really ancient biosphere was just tenuously clinging on to this inhospitable planet, and it wasn’t until the emergence of nitrogen fixation that suddenly the biosphere become large and robust and diverse,” said co-author Roger Buick, a UW professor of Earth and space sciences. “Our work shows that there was no nitrogen crisis on the early Earth, and therefore it could have supported a fairly large and diverse biosphere.”
The results were published Feb. 16 in Nature.

The authors analyzed 52 samples ranging in age from 2.75 to 3.2 billion years old, collected in South Africa and northwestern Australia. These are some of the oldest and best-preserved rocks on the planet. The rocks were formed from sediment deposited on continental margins, so are free of chemical irregularities that would occur near a subsea volcano. They also formed before the atmosphere gained oxygen, roughly 2.3 to 2.4 billion years ago, and so preserve chemical clues that have disappeared in modern rocks.

Even the oldest samples, 3.2 billion years old – three-quarters of the way back to the birth of the planet – showed chemical evidence that life was pulling nitrogen out of the air. The ratio of heavier to lighter nitrogen atoms fits the pattern of nitrogen-fixing enzymes contained in single-celled organisms, and does not match any chemical reactions that occur in the absence of life.

“Imagining that this really complicated process is so old, and has operated in the same way for 3.2 billion years, I think is fascinating,” said lead author Eva Stüeken, who did the work as part of her UW doctoral research. “It suggests that these really complicated enzymes apparently formed really early, so maybe it’s not so difficult for these enzymes to evolve.”

Genetic analysis of nitrogen-fixing enzymes have placed their origin at between 1.5 and 2.2 billion years ago.

“This is hard evidence that pushes it back a further billion years,” Buick said.

Fixing nitrogen means breaking a tenacious triple bond that holds nitrogen atoms in pairs in the atmosphere and joining a single nitrogen to a molecule that is easier for living things to use. The chemical signature of the rocks suggests that nitrogen was being broken by an enzyme based on molybdenum, the most common of the three types of nitrogen-fixing enzymes that exist now. 

Molybdenum is now abundant because oxygen reacts with rocks to wash it into the ocean, but its source on the ancient Earth – before the atmosphere contained oxygen to weather rocks – is more mysterious.

The authors hypothesize that this may be further evidence that some early life may have existed in single-celled layers on land, exhaling small amounts of oxygen that reacted with the rock to release molybdenum to the water.

“We’ll never find any direct evidence of land scum one cell thick, but this might be giving us indirect evidence that the land was inhabited,” Buick said. “Microbes could have crawled out of the ocean and lived in a slime layer on the rocks on land, even before 3.2 billion years ago.”

Future work will look at what else could have limited the growth of life on the early Earth. Stüeken has begun a UW postdoctoral position funded by NASA to look at trace metals such as zinc, copper and cobalt to see if one of them controlled the growth of ancient life.

Other co-authors are Bradley Guy at the University of Johannesburg in South Africa, who provided some samples from gold mines, and UW graduate student Matthew Koehler. The research was funded by NASA, the UW’s Virtual Planetary Laboratory, the Geological Society of America and the Agouron Institute.

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Yes, that 3D-printed mansion is safe to live in

February 13, 2015 / / 0 Comments


WinSun claims that their new 3D printed five-story building is the tallest of its kind in the world. Credit: 3ders.org
WinSun claims that their new 3D printed five-story building is the tallest of its kind in the world. 


Excerpt from

Back in April, a team of Chinese construction workers used a 3D printer to construct houses. By day’s end, there were 10 standing. They were compact and fairly bare bones — nothing much to look at besides the “wow!” factor of there being as many as — count them — 10. But this time around, those same builders have taken the wraps off an achievement that’s roundly more impressive.
In Suzhou Industrial Park, adjacent to Shanghai, stands a five-story structure that the WinSun Decoration Design Engineering firm claims is “the world’s tallest 3D-printed building.” Next to it is the equally massive 3D-printed mansion, which measures 11,840 square feet. Like the previous buildings, the walls are comprised of a mix of concrete and recycled waste materials, such as glass and steel, and formed layer by printed layer. The company stated that the total cost for the mansion was roughly $161,000. 
In a broader sense, this latest feat is yet another indication of how rapidly additive manufacturing techniques are advancing. Once used primarily as a means to quickly render miniature model versions of products, the technology has reached a point where large-scale printers are now capable of making life-sized working creations, such as automobiles, in mere days. For instance, it took less than 48 hours for start-up Local Motors to print a two-seater called the Strati into existence and drive it off the showroom.
Many of these designs, however, typically don’t amount to much beyond being passion projects meant to push 3D printing into new frontiers and drum up some publicity along the way. One example of this is the massive 3D Print Canal House that’s being constructed entirely on-site along a canal in Amsterdam, a process that’s slated to take longer and is less feasible than standard construction, Phil Reeves of UK-based 3D printing research firm Econolyst recently told CNN.
More promising, though, is a system developed by Behrokh Khoshnevis, a University of Southern California engineering professor. His concept machine, called Contour Crafting, involves a clever combination of mechanical cranes and 3D layering to print and assemble entire homes simultaneously — complete with insulation and indoor plumbing — in less than a day. 

Assembling 3D printed buildings is quite similar to erecting prefab homes. Credit: 3ders.org
Assembling 3D printed buildings is quite similar to erecting prefab homes. 


The approach employed by WinSun isn’t anywhere near that level of sophistication, but it may well prove to be the most practical – at least thus far. There is some labor and equipment costs that comes from trucking in and piecing together the various sections on-site, though the manner in which it all comes together is comparable to the ease of prefab assembly. It’s also reportedly greener thanks to the addition of recycled materials. 
To pitch the advantages of their technology, the company held a news conference to announce that they had taken on orders for 20,000 smaller units as well as highlight some significant cost-cutting figures. According toindustry news site 3Der:
The sheer size of the printer allows for a 10x increase in production efficiency. WinSun estimates that 3D printing technology can save between 30 and 60 percent of building materials and shortens production times by 50 to even 70 percent, while decreasing labor costs by 50 up to even 80 percent. Future applications include 3D printed bridges or tall office buildings that can be built right on site.
WinSun did not respond to a request to disclose how they arrived at those numbers, but Enrico Dini, an Italian civil engineer and chairman of competing start-up Monolite, says that he suspects the calculations may be a tad bit inflated. Still, he emphasized that his own data does back up the claim that, compared to conventional methods, layering may boost overall efficiency. 
“It would be very difficult to fabricate such large sections with traditional concrete casting,” he says. “With 3D printing, you have a lot less waste because you’re only printing out as much material as you need and you can custom shape whole sections on the spot, which can be a big challenge.”

WinSuns 3D printed villa has several rooms and has been deemed to be up to Chinas national safety standards. Credit: 3ders.org
WinSun’s 3D-printed villa has several rooms and has been deemed to be up to China’s national safety standards.

One major concern is whether these large-scale dwellings can hold up over time against the elements. According to 3Der, Ma Rongquan, chief engineer of China Construction Bureau, inspected the building’s structural integrity and found them to be up to code, but was careful to note that state officials have yet to establish specific criteria for assessing the long-term safety of 3D printed architecture.   
And as Dini, who supports the technology, points out, there is the possibility that the use of additive manufacturing may pose some degree of risk. “The only issue is that as the layers of concrete are bonded together, they’re drying at slightly different rates and that’s not very ideal,” he explains. “So there’s maybe a higher chance of it fracturing at the contact point if there’s a strong enough force at play.” 
Regardless, Dini says he’d feel completely safe going inside any floor of either building since construction materials used today are likely to contain special additives to enhance strength and resistance. One such formulation, fiber-reinforced Ductal, has been shown in some tests to be 10 times stronger and last twice as long as regular concrete. He stressed that walls should also be tested to ensure that other properties, such as acoustics, ventilation and thermal insulations are on par with existing buildings.
“In Italy, building standards are extremely strict,” he noted. “But I can’t say I can say the same about China.”

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How Would the World Change If We Found Alien Life?

February 8, 2015 / / 0 Comments







Excerpt from space.com
By by Elizabeth Howell

 In 1938, Orson Welles narrated a radio broadcast of "War of the Worlds" as a series of simulated radio bulletins of what was happening in real time as Martians arrived on our home planet. The broadcast is widely remembered for creating public panic, although to what extent is hotly debated today.

Still, the incident serves as an illustration of what could happen when the first life beyond Earth is discovered. While scientists might be excited by the prospect, introducing the public, politicians and interest groups to the idea could take some time.

How extraterrestrial life would change our world view is a research interest of Steven Dick, who just completed a term as the Baruch S. Blumberg NASA/Library of Congress Chair of Astrobiology. The chair is jointly sponsored by the NASA Astrobiology Program and the John W. Kluge Center, at the Library of Congress. 


Dick is a former astronomer and historian at the United States Naval Observatory, a past chief historian for NASA, and has published several books concerning the discovery of life beyond Earth. To Dick, even the discovery of microbes would be a profound shift for science.

"If we found microbes, it would have an effect on science, especially biology, by universalizing biology," he said. "We only have one case of biology on Earth. It's all related. It's all DNA-based. If we found an independent example on Mars or Europa, we have a chance of forming a universal biology."

Dick points out that even the possibilities of extraterrestrial fossils could change our viewpoints, such as the ongoing discussion of ALH84001, a Martian meteorite found in Antarctica that erupted into public consciousness in 1996 after a Science article said structures inside of it could be linked to biological activity. The conclusion, which is still debated today, led to congressional hearings.

"I've done a book about discovery in astronomy, and it's an extended process," Dick pointed out. "It's not like you point your telescope and say, 'Oh, I made a discovery.' It's always an extended process: You have to detect something, you have to interpret it, and it takes a long time to understand it. As for extraterrestrial life, the Mars rock showed it could take an extended period of years to understand it."


ALH84001 Meteorite
The ALH84001 meteorite, which in a 1996 Science publication was speculated to be host to what could be ancient Martian fossils. That finding is still under dispute today.

Mayan decipherments

In his year at the Library of Congress, Dick spent time searching for historical examples (as well as historical analogies) of how humanity might deal with first contact with an extraterrestrial civilization. History shows that contact with new cultures can go in vastly different directions.

Hernan Cortes' treatment of the Aztecs is often cited as an example of how wrong first contact can go. But there were other efforts that were a little more mutually beneficial, although the outcomes were never perfect. Fur traders in Canada in the 1800s worked closely with Native Americans, for example, and the Chinese treasure fleet of the 15th Century successfully brought its home culture far beyond its borders, perhaps even to East Africa.

Even when both sides were trying hard to make communication work, there were barriers, noted Dick.

"The Jesuits had contact with Native Americans," he pointed out. "Certain concepts were difficult, like when they tried to get across the ideas of the soul and immortality."



A second look by the Mars Global Surveyor at the so-called Viking “Face on Mars” in Cydonia revealed a more ordinary-looking hill, showing that science is an extended process of discovery.


Indirect contact by way of radio communications through the Search for Extraterrestrial Intelligence (SETI), also illustrates the challenges of transmitting information across cultures. There is historical precedence for this, such as when Greek knowledge passed west through Arab translators in the 12th Century. This shows that it is possible for ideas to be revived, even from dead cultures, he said.

It's also quite possible that the language we receive across these indirect communications would be foreign to us. Even though mathematics is often cited as a universal language, Dick said there are actually two schools of thought. One theory is that there is, indeed, one kind of mathematics that is based on a Platonic idea, and the other theory is that mathematics is a construction of the culture that you are in. 

"There will be a decipherment process. It might be more like the Mayan decipherments," Dick said.


The ethics of contact

As Dick came to a greater understanding about the potential c impact of extraterrestrial intelligence, he invited other scholars to present their findings along with him. Dick chaired a two-day NASA/Library of Congress Astrobiology Symposium called "Preparing for Discovery," which was intended to address the impact of finding any kind of life beyond Earth, whether microbial or some kind of intelligent, multicellular life form.

The symposium participants discussed how to move beyond human-centered views of defining life, how to understand the philosophical and theological problems a discovery would bring, and how to help the public understand the implications of a discovery.

"There is also the question of what I call astro-ethics," Dick said. "How do you treat alien life? How do you treat it differently, ranging from microbes to intelligence? So we had a philosopher at our symposium talking about the moral status of non-human organisms, talking in relation to animals on Earth and what their status is in relation to us."

Dick plans to collect the lectures in a book for publication next year, but he also spent his time at the library gathering materials for a second book about how discovering life beyond Earth will revolutionize our thinking.

"It's very farsighted for NASA to fund a position like this," Dick added. "They have all their programs in astrobiology, they fund the scientists, but here they fund somebody to think about what the implications might be. It's a good idea to do this, to foresee what might happen before it occurs."

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NASA probe snaps amazing image of Ceres

February 6, 2015 / / 0 Comments



    NASA's Dawn space probe has taken the sharpest-yet image of Ceres, a dwarf planet in our solar system's asteroid belt.

    Excerpt from SPACE.com

    By Mike Wall  

    NASA's Dawn spacecraft has taken the sharpest-ever photos of Ceres, just a month before slipping into orbit around the mysterious dwarf planet.

    Dawn captured the new Ceres images Wednesday (Feb. 4), when the probe was 90,000 miles (145,000 kilometers) from the dwarf planet, the largest object in the main asteroid belt between Mars and Jupiter.

    On the night of March 5, Dawn will become the first spacecraft ever to orbit Ceres — and the first to circle two different solar system bodies beyond Earth. (Dawn orbited the protoplanet Vesta, the asteroid belt's second-largest denizen, from July 2011 through September 2012.) 

    "It's very exciting," Dawn mission director and chief engineer Marc Rayman, who's based at NASA's Jet Propulsion Laboratory in Pasadena, California, said of Dawn's impending arrival at Ceres. "This is a truly unique world, something that we've never seen before."


    The 590-mile-wide (950 km) Ceres was discovered by Italian astronomer Giuseppe Piazzi in 1801. It's the only dwarf planet in the asteroid belt, and contains about 30 percent of the belt's total mass. (For what it's worth, Vesta harbors about 8 percent of the asteroid belt's mass.)

    Despite Ceres' proximity (relative to other dwarf planets such as Pluto and Eris, anyway), scientists don't know much about the rocky world. But they think it contains a great deal of water, mostly in the form of ice. Indeed, Ceres may be about 30 percent water by mass, Rayman said.

    Ceres could even harbor lakes or oceans of liquid water beneath its frigid surface. Furthermore, in early 2014, researchers analyzing data gathered by Europe's Herschel Space Observatory announced that they had spotted a tiny plume of water vapor emanating from Ceres. The detection raised the possibility that internal heat drives cryovolcanism on the dwarf planet, as it does on Saturn's moon's Enceladus. (It's also possible that the "geyser" was caused by a meteorite impact, which exposed subsurface ice that quickly sublimated into space, researchers said).

    The interior of Ceres may thus possess liquid water and an energy source — two key criteria required for life as we know it to exist.
    Dawn is not equipped to search for signs of life. But the probe — which is carrying a camera, a visible and infrared mapping spectrometer and a gamma ray and neutron spectrometer — will give scientists great up-close looks at Ceres' surface, which in turn could shed light on what's happening down below. 

    For example, Dawn may see chemical signs of interactions between subsurface water, if it exists, and the surface, Rayman said.
    "That's the sort of the thing we would be looking for — surface structures or features that show up in the camera's eye, or something about the composition that's detectable by one of our multiple spectrometers that could show evidence," he told Space.com. "But if the water doesn't make it to the surface, and isn't in large enough reservoirs to show up in the gravity data, then maybe we won't find it."

    Dawn will also attempt to spot Ceres' water-vapor plume, if it still exists, by watching for sunlight scattered off water molecules above the dwarf planet. But that's going to be a very tough observation to make, Rayman said.

    "The density of the water [observed by Herschel] is less than the density of air even above the International Space Station," he said. "For a spacecraft designed to map solid surfaces of airless bodies, that is an extremely difficult measurement." 

    Merging onto the freeway

    Dawn is powered by low-thrust, highly efficient ion engines, so its arrival at Ceres will not be a nail-biting affair featuring a make-or-break engine burn, as most other probes' orbital insertions are.

    Indeed, as of Friday (Feb. 6), Dawn is closing in on Ceres at just 215 mph (346 km/h), Rayman said —and that speed will keep decreasing every day.

    "You take a gentle, curving route, and then you slowly and safely merge onto the freeway, traveling at the same speed as your destination," Rayman said. "Ion propulsion follows that longer, more gentle, more graceful route."

    Dawn won't start studying Ceres as soon as it arrives. The spacecraft will gradually work its way down to its first science orbit, getting there on April 23. Dawn will then begin its intensive observations of Ceres, from a vantage point just 8,400 miles (13,500 km) above the dwarf planet's surface.

    The science work will continue — from a series of increasingly closer-in orbits, including a low-altitude mapping orbit just 230 miles (375 km) from Ceres' surface — through June 30, 2016, when the $466 million Dawn mission is scheduled to end.
    Rayman can't wait to see what Dawn discovers.

    "After looking through telescopes at Ceres for more than 200 years, I just think it's really going to be exciting to see what this exotic, alien world looks like," he said. "We're finally going to learn about this place."

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    The Mystery of the Blonde-haired Tarim Mummies of China

    February 6, 2015 / / 0 Comments



    Excerpt from 
    historicmysteries.com
    By Shelly Barclay

    The Tarim Mummies or the Mummies of Xinjiang are mysterious mummies that were discovered in the foothills of the Tian Shan Mountains in China. What is so mysterious about them is that some of them date back to roughly 4,000 years ago, a time when it was thought that there were no westerners in that area. However, there must have been, because the Tarim mummies are Caucasian. Not only that, but they wear similar garments and share similar burial practices of some European countries.



    The first of the Tarim mummies was discovered by Wang Binghua in 1978. Wang had been searching for ancient settlements along in the northeast of Xinjiang when a local man directed him to Quizilchoqa. It was there that Wang uncovered the first mysterious Tarim mummy. Over time, these mummies were discovered in four different sites in the Tarim Basin area.  More than one hundred of them have been uncovered so far.


    The Tarim mummies are unusually well preserved. This is interesting because the people who buried them did not practice mummification. The sites where these mummies have been found, lie on the edges of the Taklamakan Desert. When these ancient people buried their dead, the hot climate and rocky soil helped to keep the deceased’s body preserved, though it should have decomposed hundreds of years ago. Some of these corpses rival the Ancient Egyptian mummies in their extraordinary preserved state.
    Another very strange thing about the Tarim mummies is the attire in which they were buried. If the fact that some of them had blond hair and blue eyes hadn’t given away the fact that they were westerners that had settled in what is now Xinjiang, the clothing they wore when they were buried would have. 


    One of the mummies, the Yingpan Man, was six feet six inches tall and wore a red tunic with gold embroidery. He also wore a gold foil burial mask. This burial clothing is far more indicative of western influence than of Eastern. Other Tarim mummies have also been found wearing decidedly western clothing. One of the oddest bits of clothing found any of these mummies are the flat-brimmed pointy “witch hats” that were discovered on the “Witches of Subeshi.”

    Researchers have been able to decipher a number of things about the people who buried these mummies since their discovery. This is largely due to the work of Dr. Victor Mair, the man who brought the Tarim mummies into the public eye. It is known that the ancient people rode horses, used chariots and had at least some medical knowledge. One of the Tarim mummies was found with evidence of a surgical wound on its neck, which had been sutured at some point.

    Since the discovery of the caucasian-featured Tarim mummies in Xinjiang, scientists have been trying to uncover links between the ancient people who buried these mummies and modern citizens of the area. Thus far, several links have been discovered and hypothesized, but it is difficult to make them public or credible because of political unrest in the area. Nonetheless, there are many people who are certain that the Tarim mummies represent the first Caucasians to settle in the area. If this is fact, then it will mean that western man settled in the area roughly one thousand years before scientists had previously thought they did.

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    Robots Can Learn to Perform Tasks by “Watching” YouTube Videos

    February 1, 2015 / / 0 Comments


    https://i0.wp.com/www.darpa.mil/uploadedImages/Content/NewsEvents/Releases/2015/MSEEresearchers.png?resize=640%2C428
    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  

    Robots can learn to recognize objects and patterns fairly well, but to interpret and be able to act on visual input is much more difficult.  Researchers at the University of Maryland, funded by DARPA’s Mathematics of Sensing, Exploitation and Execution (MSEE) program, recently developed a system that enabled robots to process visual data from a series of “how to” cooking videos on YouTube. Based on what was shown on a video, robots were able to recognize, grab and manipulate the correct kitchen utensil or object and perform the demonstrated task with high accuracy—without additional human input or programming.  

    “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

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    Elon Musk drops space plans into Seattle’s lap

    February 1, 2015 / / 0 Comments




    Excerpt from seattletimes.com

    Elon Musk thought three major trends would drive the future: the Internet, the quest for sustainable energy and space exploration. He’s got skin in all three games.

    Of all the newcomers we’ve seen here lately, one of the more interesting is Elon Musk.

    The famous entrepreneur isn’t going to live here, at least not yet. But earlier this month he did announce plans to bulk up an engineering center near Seattle for his SpaceX venture. The invitation-only event was held in the shadow of the Space Needle.
    If the plan happens, SpaceX would join Planetary Resources and Blue Origin in a budding Puget Sound space hub. With talent from Boeing, the aerospace cluster and University of Washington, this offers fascinating potential for the region’s future.

    Elon Musk sounds like the name of a character from a novel that would invariably include the sentence, “he had not yet decided whether to use his powers for good or for evil.”

    He is said to have been the inspiration for the character Tony Stark, played by Robert Downey Jr. in the “Iron Man” movies. He’s also been compared to Steve Jobs and even Thomas Edison.

    The real Musk seems like a nice-enough chap, at least based on his ubiquitous appearances in TED talks and other venues.

    Even the semidishy essay in Marie Claire magazine by his first wife, Justine, is mostly about the challenge to the marriage as Musk became very rich, very young, started running with a celebrity crowd and exhibited the monomaniacal behavior common to the entrepreneurial tribe.

    A native of South Africa, Musk emigrated to Canada and finally to the United States, where he received degrees from the University of Pennsylvania’s prestigious Wharton School. He left Stanford’s Ph.D. program in applied physics after two days to start a business.
    In 1995, he co-founded Zip2, an early Internet venture for newspapers. Four years later, he co-founded what would become PayPal. With money from eBay’s acquisition of PayPal, he started SpaceX. He also invested in Tesla Motors, the electric-car company, eventually becoming chief executive. Then there’s Solar City, a major provider of solar-power systems.

    Musk has said that early on he sensed three major trends would drive the future: the Internet, the quest for sustainable energy and space exploration. He’s got skin in all three games.

    At age 43, Musk is seven years younger than Jeff Bezos and more than 15 years younger than Bill Gates.

    His achievements haven’t come without controversy. Tesla played off several states against each other for a battery factory. Nevada, desperate to diversify its low-wage economy, won, if you can call it that.

    The price tag was $1.4 billion in incentives and whether it ever pays off for the state is a big question. A Fortune magazine investigation showed Musk not merely as a visionary but also a master manipulator with a shaky deal. Musk, no shrinking violet, fired back on his blog.

    SpaceX is a combination of the practical and the hyperambitious, some would say dreamy.

    On the practical side, the company is one of those chosen by the U.S. government to resupply the International Space Station. Musk also hopes to put 4,000 satellites in low-Earth orbit to provide inexpensive Internet access worldwide.

    The satellite venture will be based here, with no financial incentives from the state.

    But he also wants to make space travel less expensive, generate “a lot of money” through SpaceX, and eventually establish a Mars colony.

    “SpaceX, or some combination of companies and governments, needs to make progress in the direction of making life multiplanetary, of establishing a base on another planet, on Mars — being the only realistic option — and then building that base up until we’re a true multiplanet species,” he said during a TED presentation.

    It’s heady stuff. And attractive enough to lead Google and Fidelity Investments to commit $1 billion to SpaceX.

    Also, in contrast with the “rent-seeking” and financial plays of so many of the superwealthy, Musk actually wants to create jobs and solve practical problems.

    If there’s a cautionary note, it is that market forces alone can’t address many of our most serious challenges. Indeed, in some cases they make them worse.

    Worsening income inequality is the work of the hidden hand, unfettered by antitrust regulation, progressive taxation, unions and protections against race-to-the-bottom globalization.

    If the hidden costs of spewing more carbon into the atmosphere are not priced in, we have today’s market failure exacerbating climate change. Electric cars won’t fix that as long as the distortions favoring fossil fuels remain.

    So a broken, compromised government that’s cutting research dollars and failing to invest in education and forward-leaning infrastructure is a major impediment.

    The United States did not reach the moon because of a clever billionaire, but through a national endeavor to serve the public good. I know, that’s “so 20th century.” 

    Also, as Northwestern University economist Robert Gordon might argue, visionaries such as Thomas Edison grabbed relatively low-hanging fruit, with electrification creating huge numbers of jobs. 

    Merely recovering the lost demand of the Great Recession has proved difficult. Another electrificationlike revolution that lifts all boats seems improbable.

    I’m not sure that’s true. But it will take more than Iron Man to rescue the many Americans still suffering.

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    Why Bill Nye ‘The Science Guy’ Calls Evolution ‘Undeniable’ and Creationism ‘Inane’

    January 26, 2015 / / 0 Comments



    Picture of thousands of galaxies
    Gazing at galaxy clusters like Abell 2218, it's hard to imagine how we fit into the cosmos. Evolution can help with that, says Bill Nye.
    Photograph by NASA, ESA, and Johan Richard (Caltech, USA)


    Darwin's theory explains so much of the world, from bumblebees to human origins, says the Science Guy.


    Excerpt from
    By Jane J. Lee

    With a jaunty bow tie and boyish enthusiasm, Bill Nye the Science Guy has spent decades decoding scientific topics, from germs to volcanoes, for television audiences. Last February, the former engineer defended the theory of evolution in a televised debate with young-Earth creationist Ken Ham, a vocal member of a group that believes the Earth is only 6,000 years old. Nye's decision to engage Ham kicked up plenty of criticism from scientists and creationists alike.

    The experience prompted the celebrity science educator to write a "primer" on the theory of evolution called Undeniable: Evolution and the Science of Creation. In his new book, Nye delights in how this fundamental discovery helps to unlock the mysteries of everything from bumblebees to human origins to our place in the universe.

    Who do you hope will read this book?
    Grown-ups who have an interest in the world around them, people coming of age who have an interest in science, people who still want to know how the world works.

    This is the big concern of mine with respect to the organization Answers in Genesis and Ken Ham and all those guys: their relentless, built-in attempts to indoctrinate a generation of science students on a worldview that is obviously wrong.

    I worry about these kids—they're part of my society. We can't raise a generation of students who don't understand the fundamental idea in all of life science, any more than you want to raise a generation of kids who don't understand chemistry or physics or arithmetic.

    How and when did you first encounter creationism?
    About 20 years ago. I was a member of the Northwest Skeptics, which is the Seattle-based skeptics organization. We met people who insisted that the Earth was 6,000 years old. The inanity took my breath away. When you understand anything about astronomy or have just a rudimentary understanding of radioactivity, the Earth is patently not 6,000 years old. It's silly.

    It's been said that a good way of convincing people of something is to appeal to their emotions. What do you think?
    That's my business! In the book, I purposely spend a lot of time in the first person. The reason is, we find stories compelling. Stories are how we remember things, how we organize things.

    By telling a story in the first person, it's hard to dismiss. If I say, "I remember the time I met Ivan the gorilla," it's really difficult for the listener or reader to go, "No, you don't!"

    When you say, "I feel," it's really hard for the reader to say, "No, you don't." Yes, I do. I did a lot of that in the book...

    Picture of a sweat bee pollinating a deadly nightshade flower
    A fascination with bees and flight drew a young Bill Nye into the world of science and evolution.
    Photograph by Mark W Moffett, National Geographic



    Picture of the Earth seen from the International Space Station
    One of the most fundamental ideas in explaining life on Earth is the theory of evolution, says Nye.
    Photograph by NASA Earth Observatory

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    The Best Star Gazing Binoculars for 2015

    January 24, 2015 / / 0 Comments




    Excerpt from space.com

    Most people have two eyes. Humans evolved to use them together (not all animals do). People form a continuous, stereoscopic panorama movie of the world within in their minds. With your two eyes tilted upward on a clear night, there's nothing standing between you and the universe. The easiest way to enhance your enjoyment of the night sky is to paint your brain with two channels of stronger starlight with a pair of binoculars. Even if you live in — or near — a large, light-polluted city, you may be surprised at how much astronomical detail you'll see through the right binoculars!
    Our editors have looked at the spectrum of current binocular offerings. Thanks to computer-aided design and manufacturing, there have never been more high-quality choices at reasonable prices. Sadly, there's also a bunch of junk out there masquerading as fine stargazing instrumentation. We've selected a few that we think will work for most skywatchers.
    There was a lot to consider: magnification versus mass, field of view, prism type, optical quality ("sharpness"), light transmission, age of the user (to match "exit pupil" size, which changes as we grow older), shock resistance, waterproofing and more. 

    The best binoculars for you

    "Small" astronomy binoculars would probably be considered "medium" for bird watching, sports observation and other terrestrial purposes. This comes about as a consequence of optics (prism type and objective size, mostly). "Large" binoculars are difficult to use for terrestrial applications and have a narrow field of view. They begin to approach telescope quality in magnification, resolution and optical characteristics.

    Most of our Editors' Choicesfor stargazing binoculars here are under $300. You can pay more than 10 times that for enormous binocular telescopes used by elite enthusiasts on special mounts! You'll also pay more for ruggedized ("mil spec," or military standard) binoculars, many of which suspend their prisms on shock mounts to keep the optics in precise alignment.

    Also, our Editors' Choices use Porro prism optics. Compact binoculars usually employ "roof" prisms, which can be cast more cheaply, but whose quality can vary widely. [There's much more about Porro prisms in our Buyer's Guide.]
    We think your needs are best served by reviewing in three categories.
    • Small, highly portable binoculars can be hand-held for viewing ease.
    • Medium binoculars offer higher powers of magnification, but still can be hand-held, if firmly braced.
    • Large binoculars have bigger "objective" lenses but must be mounted on a tripod or counterweighted arm for stability.
    Here's a detailed look at our Editor's Choice selections for stargazing binoculars:

    Best Small Binoculars 

    Editor's Choice: Oberwerk Mariner 8x40 (Cost: $150)

    Oberwerk in German means "above work." The brand does indeed perform high-level optical work, perfect for looking at objects above, as well as on the ground or water. Founder Kevin Busarow's Mariner series is not his top of the line, but it benefits greatly from engineering developed for his pricier models. The Oberwerk 8x40’s treat your eyes to an extremely wide field, at very high contrast, with razor-sharp focus; they are superb for observing the broad starscapes of the Milky Way. Just 5.5 inches (14 cm) from front to back and 6.5 inches wide (16.5 cm), the Mariners are compact and rugged enough to be your favorite "grab and go binoculars." But at 37 ounces, they may be more than a small person wants to carry for a long time.


    Runner-Up: Celestron Cometron 7x50 (Cost: $30)

    Yes, you read that price correctly! These Celestron lightweight, wide-field binoculars bring honest quality at a remarkably low price point. The compromise comes in the optics, particularly the prism's glass type (you might see a little more chromatic aberration around the edges of the moon, and the exit pupil isn't a nice, round circle). Optimized for "almost infinitely distant" celestial objects, these Cometrons won't focus closer than about 30 feet (9.1 meters).  But that's fine for most sports and other outdoor use. If you're gift-buying for multiple young astronomers – or you want an inexpensive second set for yourself – these binoculars could be your answer. Just maybe remind those young folks to be a little careful around water; Celestron claims only that the Cometrons are "water resistant," not waterproof. 


    Honorable Mention: Swarovski Habicht 8x30 (Cost: $1,050)

    From the legendary Austrian firm of Swarovski Optik, these "bins" are perfect. Really. Very sharp. Very lightweight. Very wide field. Very versatile. And very expensive! Our editors would have picked them if we could have afforded them. 

    Honorable Mention: Nikon Aculon 7x50 (Cost: $110) 

    Nikon's legendary optical quality and the large, 7mm exit pupil diameter make these appropriate as a gift for younger skywatchers. 

    Best Medium Binoculars

    Editor's Choice: Celestron SkyMaster 8x56 (Cost: $210)

    A solid, chunky-feeling set of quality prisms and lenses makes these binoculars a pleasant, 38oz. handful. A medium wide 5.8 degrees filed of view and large 7mm exit pupil brings you gently into a sweet sky of bright, though perhaps not totally brilliant, stars. Fully dressed in a rubber wetsuit, these SkyMasters are waterproof. Feel free to take them boating or birding on a moist morning. Their optical tubes were blown out with dry nitrogen at the factory, then sealed. So you can expect them not to fog up, at least not from the inside. Celestron's strap-mounting points on the Skymaster 8x56 are recessed, so they don't bother your thumbs, but that location makes them hard to fasten. 


    Runner-Up: Oberwerk Ultra 15x70 (Cost: $380)

    The most rugged pair we evaluated, these 15x70s are optically outstanding. Seen through the Ultra's exquisitely multi-coated glass, you may find yourself falling in love with the sky all over again. Oberwerk's method of suspending their BAK4 glass Porro prisms offers greater shock-resistance than most competitors’ designs. While more costly than some comparable binoculars, they deliver superior value. Our only complaint is with their mass: At 5.5 lbs., these guys are heavy!  You can hand-hold them for a short while, if you’re lying down. But they are best placed on a tripod, or on a counterweighted arm, unless you like shaky squiggles where your point-source stars are supposed to be. Like most truly big binoculars, the eyepieces focus independently; there’s no center focus wheel. These "binos" are for true astronomers. 


    Honorable Mention: Vixen Ascot 10x50 (Cost:$165)

    These quirky binoculars present you with an extremely wide field. But they are not crash-worthy – don't drop them in the dark – nor are they waterproof, and the focus knob is not conveniently located. So care is needed if you opt for these Vixen optics. 

    Best Large Binoculars

    Don't even think about hand-holding this 156-ounce beast! The SkyMaster 25x100 is really a pair of side-by-side 100mm short-tube refractor telescopes. Factor the cost of a sturdy tripod into your purchase decision, if you want to go this big.  The monster Celestron comes with a sturdy support spar for mounting. Its properly multi-coated optics will haul in surprising detail from the sky.  Just make sure your skies are dark; with this much magnification, light pollution can render your images dingy. As with many in the giant and super-giant class of binoculars, the oculars (non-removable eyepieces) focus separately, each rotating through an unusually long 450 degrees.  Getting to critical focus can be challenging, but the view is worth it. You can resolve a bit of detail on face of the new moon (lit by "Earthshine") and pick out cloud bands on Jupiter; tha's pretty astonishing for binoculars. 


    Runner-Up: Orion Astronomy 20x80 (Cost: $150)

    These big Orions distinguish themselves by price point; they're an excellent value. You could pay 10 times more for the comparably sized Steiners Military Observer 20x80 binoculars! Yes, the Orions are more delicate, a bit less bright and not quite as sharp. But they do offer amazingly high contrast; you'll catch significant detail in galaxies, comets and other "fuzzies." Unusually among such big rigs, the Astronomy 20x80 uses a center focus ring and one "diopter" (rather than independently focusing oculars); if you’re graduating from smaller binoculars, which commonly use that approach, this may be a comfort. These binoculars are almost lightweight enough to hold them by hand. But don't do that, at least not for long periods. And don't drop them. They will go out of alignment if handled roughly. 


    Honorable Mention: Barska Cosmos 25x100 (Cost: $230)

    They are not pretty, but you're in the dark, right? Built around a tripod-mountable truss tube, these Barskas equilibrate to temperature quickly and give you decent viewing at rational cost. They make for a cheaper version of our Editors' Choice Celestron SkyMasters. 

    Honorable Mention: Steiner Observer 20x80 (Cost: $1,500)

    Not at all a practical cost choice for a beginning stargazer, but you can dream, can't you? These Steiner binoculars are essentially military optics "plowshared" for peaceful celestial observing. 

    Why we chose NOT to review certain types

    Image stabilized?

    Binoculars with active internal image stabilization are a growing breed. Most use battery-powered gyroscope/accelerometer-driven dynamic optical elements. We have left this type out of our evaluation because they are highly specialized and pricey ($1,250 and up). But if you are considering active stabilization, you can apply the same judgment methods detailed in our Buyer's Guide.

    Comes with a camera?

    A few binoculars are sold with built-in cameras. That seems like a good idea. But it isn't, at least not for skywatching. Other than Earth's moon, objects in the night sky are stingy with their photons. It takes a lengthy, rock-steady time exposure to collect enough light for a respectable image. By all means, consider these binocular-camera combos for snapping Facebook shots of little Jenny on the soccer field. But stay away from them for astronomy.

    Mega monster-sized?

    Take your new binoculars out under the night sky on clear nights, and you will fall in love with the universe. You will crave more ancient light from those distant suns. That may translate into a strong desire for bigger stereo-light buckets.

    Caution: The next level up is a quantum jump of at least one financial order of magnitude. But if you have the disposable income and frequent access to dark skies, you may want to go REALLY big. Binocular telescopes in this class can feature interchangeable matching eyepieces, individually focusing oculars, more than 30x magnification and sturdy special-purpose tripods. Amateurs using these elite-level stereoscopes have discovered several prominent comets.

    Enjoy your universe

    If you are new to lens-assisted stargazing, you'll find excellent enhanced views among the binocular choices above. To get in deeper and to understand how we picked the ones we did, jump to our Buyer's Guide: How to Choose Binoculars for Sky Watching.

    You have just taken the first step to lighting up your brain with star fire. May the photons be with you. Always. 

    Skywatching Events 2015

    Once you have your new binoculars, it's time to take them for a spin. This year intrepid stargazers will have plenty of good opportunities to use new gear.

    On March 20, for example, the sun will go through a total solar eclipse. You can check out the celestial sight using the right sun-blocking filters for binoculars, but NEVER look at the sun directly, even during a solar eclipse. It's important to find the proper filters in order to observe the rare cosmic show. 

    Observers can also take a look at the craggy face of the moon during a lunar eclipse on April 4. Stargazers using binoculars should be able to pick out some details not usually seen by the naked eye when looking at Earth's natural satellite.

    Skywatchers should also peek out from behind the binoculars for a chance to see a series of annual meteor showers throughout the year.

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    Time to see Comet Lovejoy fly past Pleiades before it leaves for 8,000 years

    January 24, 2015 / / 0 Comments

    Comet C/2014 Q2 (Lovejoy) is visible to sky watchers using binoculars on clear nights in January 2015. (Jet Propulsion Laboratory)California sky watchers may be able to see two celestial bodies zooming past Earth in the next few days with just a pair...

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    Using X-rays, scientists read 2,000 year old scrolls charred by Mount Vesuvius

    January 20, 2015 / / 0 Comments


    Mount Vesuvius today



    By Amina Khan 
    Excerpt from latimes.com

    Talk about reading between the lines! Scientists wielding X-rays say they can, for the first time, read words inside the charred, rolled-up scrolls that survived the catastrophic eruption of Mt. Vesuvius nearly two millenniums ago.
    Testing the scroll
    Researchers Daniel Delattre, left, and Emmanuel Brun observe the scroll before X-ray phase contrast imaging begins. (J. Delattre)
    The findings, described in the journal Nature Communications, give hope to researchers who have until now been unable to read these delicate scrolls without serious risk of destroying them.
    The scrolls come from a library in Herculaneum, one of several Roman towns that, along with Pompeii, was destroyed when Mt. Vesuvius erupted in AD 79. This library, a small room in a large villa, held hundreds of handwritten papyrus scrolls that had been carbonized from a furnace-like blast of 608-degree-Fahrenheit gas produced by the volcano.

    “This rich book collection, consisting principally of Epicurean philosophical texts, is a unique cultural treasure, as it is the only ancient library to survive together with its books,” the study authors wrote. “The texts preserved in these papyri, now mainly stored in the Officina dei Papiri in the National Library of Naples, had been unknown to scholars before the discovery of the Herculaneum library, since they had not been copied and recopied in late Antiquity, the middle ages and Renaissance.”
    So researchers have tried every which way to read these rare and valuable scrolls, which could open a singular window into a lost literary past. The problem is, these scrolls are so delicate that it’s nearly impossible to unroll them without harming them. That hasn’t kept other researchers from trying, however – sometimes successfully, and sometimes not.

    “Different opening techniques, all less effective, have been tried over the years until the so-called ‘Oslo method’ was applied in the 1980s on two Herculaneum scrolls now in Paris with problematic results, since the method required the rolls to be picked apart into small pieces,” the study authors wrote. (Yikes.)

    Any further attempts to physically open these scrolls were called off since then, they said, “because an excessive percentage of these ancient texts was irretrievably lost by the application of such methods.”
    This is where a technique like X-ray computed tomography, which could penetrate the rolled scrolls, would come in handy. The problem is, the ancient writers used ink made of carbon pulled from smoke residue. And because the papyrus had been carbonized from the blazing heat, both paper and ink are made of roughly the same stuff. Because the soot-based ink and baked paper have about the same density, until now it’s been practically impossible to tell ink and paper apart.

    But a team led by Vito Mocella of the Institute for Microelectronics and Microsystems in Naples, Italy, realized they could use a different technique called X-ray phase-contrast tomography. Unlike the standard X-ray CT scans, X-ray phase-contrast tomography examines phase shifts in the X-ray light as it passes through different structures.
    Using the technique, the scientists were able to make out a few words and letters from two scrolls, one of them still rolled.

    Reading these scrolls is difficult; computer reconstructions of the rolled scroll reveal that the blast of volcanic material so damaged its once-perfect whorls that its cross section looks like a half-melted tree-ring pattern. The paper inside has been thoroughly warped, and some of the letters on the paper probably distorted almost beyond recognition.
    Nonetheless, the researchers were able to read a number of words and letters, which were about 2 to 3 millimeters in size. On an unrolled fragment of a scroll called “PHerc.Paris. 1,” they were able to make up the words for “would fall” and “would say.” In the twisted, distorted layers of the rolled-up papyrus called “PHerc.Paris. 4,” they could pick out individual letters: alpha, nu, eta, epsilon and others.

    The letters in “PHerc.Paris. 4” are also written in a distinctive style with certain decorative flourishes that seemed very similar to a scroll called “PHerc. 1471,” which holds a text written by the Epicurean philosopher Philodemus. The researchers think they were written in the second quarter of the first century BC.


    Ultimately, the researchers wrote, this work was a proofof concept to give other researchers a safe and reliable way to explore ancient philosophical works that were until now off-limits to them.

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