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| 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.
The Future of Technology in 2015?
Excerpt from
cnet.com
The year gone by brought us more robots, worries about artificial intelligence, and difficult lessons on space travel. The big question: where's it all taking us?
Every year, we capture a little bit more of the future -- and yet the future insists on staying ever out of reach.
Consider space travel. Humans have been traveling beyond the atmosphere for more than 50 years now -- but aside from a few overnights on the moon four decades ago, we have yet to venture beyond low Earth orbit.
Or robots. They help build our cars and clean our kitchen floors, but no one would mistake a Kuka or a Roomba for the replicants in "Blade Runner." Siri, Cortana and Alexa, meanwhile, are bringing some personality to the gadgets in our pockets and our houses. Still, that's a long way from HAL or that lad David from the movie "A.I. Artificial Intelligence."
Self-driving cars? Still in low gear, and carrying some bureaucratic baggage that prevents them from ditching certain technology of yesteryear, like steering wheels.
And even when these sci-fi things arrive, will we embrace them? A Pew study earlier this year found that Americans are decidedly undecided. Among the poll respondents, 48 percent said they would like to take a ride in a driverless car, but 50 percent would not. And only 3 percent said they would like to own one.
"Despite their general optimism about the long-term impact of technological change," Aaron Smith of the Pew Research Center wrote in the report, "Americans express significant reservations about some of these potentially short-term developments" such as US airspace being opened to personal drones, robot caregivers for the elderly or wearable or implantable computing devices that would feed them information.
Let's take a look at how much of the future we grasped in 2014 and what we could gain in 2015.
Space travel: 'Space flight is hard'
In 2014, earthlings scored an unprecedented achievement in space exploration when the European Space Agency landed a spacecraft on a speeding comet, with the potential to learn more about the origins of life. No, Bruce Willis wasn't aboard. Nobody was. But when the 220-pound Philae lander, carried to its destination by the Rosetta orbiter, touched down on comet 67P/Churyumov-Gerasimenko on November 12, some 300 million miles from Earth, the celebration was well-earned.A shadow quickly fell on the jubilation, however. Philae could not stick its first landing, bouncing into a darker corner of the comet where its solar panels would not receive enough sunlight to charge the lander's batteries. After two days and just a handful of initial readings sent home, it shut down. For good? Backers have allowed for a ray of hope as the comet passes closer to the sun in 2015. "I think within the team there is no doubt that [Philae] will wake up," lead lander scientist Jean-Pierre Bibring said in December. "And the question is OK, in what shape? My suspicion is we'll be in good shape."
The trip for NASA's New Horizons spacecraft has been much longer: 3 billion miles, all the way to Pluto and the edge of the solar system. Almost nine years after it left Earth, New Horizons in early December came out of hibernation to begin its mission: to explore "a new class of planets we've never seen, in a place we've never been before," said project scientist Hal Weaver. In January, it will begin taking photos and readings of Pluto, and by mid-July, when it swoops closest to Pluto, it will have sent back detailed information about the dwarf planet and its moon, en route to even deeper space.
Also in December, NASA made a first test spaceflight of its Orion capsule on a quick morning jaunt out and back, to just over 3,600 miles above Earth (or approximately 15 times higher than the International Space Station). The distance was trivial compared to those those traveled by Rosetta and New Horizons, and crewed missions won't begin till 2021, but the ambitions are great -- in the 2030s, Orion is expected to carry humans to Mars.
In late March 2015, two humans will head to the ISS to take up residence for a full year, in what would be a record sleepover in orbit. "If a mission to Mars is going to take a three-year round trip," said NASA astronaut Scott Kelly, who will be joined in the effort by Russia's Mikhail Kornienko, "we need to know better how our body and our physiology performs over durations longer than what we've previously on the space station investigated, which is six months."
There were more sobering moments, too, in 2014. In October, Virgin Galactic's sleek, experimental SpaceShipTwo, designed to carry deep-pocketed tourists into space, crashed in the Mojave Desert during a test flight, killing one test pilot and injuring the other. Virgin founder Richard Branson had hoped his vessel would make its first commercial flight by the end of this year or in early 2015, and what comes next remains to be seen. Branson, though, expressed optimism: "Space flight is hard -- but worth it," he said in a blog post shortly after the crash, and in a press conference, he vowed "We'll learn from this, and move forward together." Virgin Galactic could begin testing its next spaceship as soon as early 2015.
The crash of SpaceShipTwo came just a few days after the explosion of an Orbital Sciences rocket lofting an unmanned spacecraft with supplies bound for the International Space Station. And in July, Elon Musk's SpaceX had suffered the loss of one of its Falcon 9 rockets during a test flight. Musk intoned, via Twitter, that "rockets are tricky..."
Still, it was on the whole a good year for SpaceX. In May, it unveiled its first manned spacecraft, the Dragon V2, intended for trips to and from the space station, and in September, it won a $2.6 billion contract from NASA to become one of the first private companies (the other being Boeing) to ferry astronauts to the ISS, beginning as early as 2017. Oh, and SpaceX also has plans to launch microsatellites to establish low-cost Internet service around the globe, saying in November to expect an announcement about that in two to three months -- that is, early in 2015.
One more thing to watch for next year: another launch of the super-secret X-37B space place to do whatever it does during its marathon trips into orbit. The third spaceflight of an X-37B -- a robotic vehicle that, at 29 feet in length, looks like a miniature space shuttle -- ended in October after an astonishing 22 months circling the Earth, conducting "on-orbit experiments."
Self-driving cars: Asleep at what wheel?
Spacecraft aren't the only vehicles capable of autonomous travel -- increasingly, cars are, too. Automakers are toiling toward self-driving cars, and Elon Musk -- whose name comes up again and again when we talk about the near horizon for sci-fi tech -- says we're less than a decade away from capturing that aspect of the future. In October, speaking in his guise as founder of Tesla Motors, Musk said: "Like maybe five or six years from now I think we'll be able to achieve true autonomous driving where you could literally get in the car, go to sleep and wake up at your destination." (He also allowed that we should tack on a few years after that before government regulators give that technology their blessing.)Google has long been working on its own robo-cars, and until this year, that meant taking existing models -- a Prius here, a Lexus there -- and buckling on extraneous gear. Then in May, the tech titan took the wraps off a completely new prototype that it had built from scratch. (In December, it showed off the first fully functional prototype.) It looked rather like a cartoon car, but the real news was that there was no steering wheel, gas pedal or brake pedal -- no need for human controls when software and sensors are there to do the work.
Or not so fast. In August, California's Department of Motor Vehicles declared that Google's test vehicles will need those manual controls after all -- for safety's sake. The company agreed to comply with the state's rules, which went into effect in September, when it began testing the cars on private roads in October.
Regardless of who's making your future robo-car, the vehicle is going to have to be not just smart, but actually thoughtful. It's not enough for the car to know how far it is from nearby cars or what the road conditions are. The machine may well have to make no-win decisions, just as human drivers sometimes do in instantaneous, life-and-death emergencies. "The car is calculating a lot of consequences of its actions," Chris Gerdes, an associate professor of mechanical engineering, said at the Web Summit conference in Dublin, Ireland, in November. "Should it hit the person without a helmet? The larger car or the smaller car?"
Robots: Legging it out
So when do the robots finally become our overlords? Probably not in 2015, but there's sure to be more hand-wringing about both the machines and the artificial intelligence that could -- someday -- make them a match for homo sapiens. At the moment, the threat seems more mundane: when do we lose our jobs to a robot?The inquisitive folks at Pew took that very topic to nearly 1,900 experts, including Vint Cerf, vice president at Google; Web guru Tim Bray; Justin Reich of Harvard University's Berkman Center for Internet & Society; and Jonathan Grudin, principal researcher at Microsoft. According to the resulting report, published in August, the group was almost evenly split -- 48 percent thought it likely that, by 2025, robots and digital agents will have displaced significant numbers of blue- and white-collar workers, perhaps even to the point of breakdowns in the social order, while 52 percent "have faith that human ingenuity will create new jobs, industries, and ways to make a living, just as it has been doing since the dawn of the Industrial Revolution."
Still, for all of the startling skills that robots have acquired so far, they're often not all there yet. Here's some of what we saw from the robot world in 2014:
Teamwork: Researchers at the École Polytechnique Fédérale De Lausanne in May showed off their "Roombots," cog-like robotic balls that can join forces to, say, help a table move across a room or change its height.
A sense of balance: We don't know if Boston Dynamics' humanoid Atlas is ready to trim bonsai trees, but it has learned this much from "The Karate Kid" (the original from the 1980s) -- it can stand on cinder blocks and hold its balance in a crane stance while moving its arms up and down.
Catlike jumps: MIT's cheetah-bot gets higher marks for locomotion. Fed a new algorithm, it can run across a lawn and bound like a cat. And quietly, too. "Our robot can be silent and as efficient as animals. The only things you hear are the feet hitting the ground," MIT's Sangbae Kim, a professor of mechanical engineering, told MIT News. "This is kind of a new paradigm where we're controlling force in a highly dynamic situation. Any legged robot should be able to do this in the future."
Sign language: Toshiba's humanoid Aiko Chihira communicated in Japanese sign language at the CEATEC show in October. Her rudimentary skills, limited for the moment to simple messages such as signed greetings, are expected to blossom by 2020 into areas such as speech synthesis and speech recognition.
Dance skills: Robotic pole dancers? Tobit Software brought a pair, controllable by an Android smartphone, to the Cebit trade show in Germany in March. More lifelike was the animatronic sculpture at a gallery in New York that same month -- but what was up with that witch mask?
Emotional ambition: Eventually, we'll all have humanoid companions -- at least, that's always been one school of thought on our robotic future. One early candidate for that honor could be Pepper, from Softbank and Aldebaran Robotics, which say the 4-foot-tall Pepper is the first robot to read emotions. This emo-bot is expected to go on sale in Japan in February.
Ray guns: Ship shape
Damn the photon torpedoes, and full speed ahead. That could be the motto for the US Navy, which in 2014 deployed a prototype laser weapon -- just one -- aboard a vessel in the Persian Gulf. Through some three months of testing, the device "locked on and destroyed the targets we designated with near-instantaneous lethality," Rear Adm. Matthew L. Klunder, chief of naval research, said in a statement. Those targets were rather modest -- small objects mounted aboard a speeding small boat, a diminutive Scan Eagle unmanned aerial vehicle, and so on -- but the point was made: the laser weapon, operated by a controller like those used for video games, held up well, even in adverse conditions.Artificial intelligence: Danger, Will Robinson?
What happens when robots and other smart machines can not only do, but also think? Will they appreciate us for all our quirky human high and low points, and learn to live with us? Or do they take a hard look at a species that's run its course and either turn us into natural resources, "Matrix"-style, or rain down destruction?Musk himself more than once in 2014 invoked the likes of the "Terminator" movies and the "scary outcomes" that make them such thrilling popcorn fare. Except that he sees a potentially scary reality evolving. In an interview with CNBC in June, he spoke of his investment in AI-minded companies like Vicarious and Deep Mind, saying: "I like to just keep an eye on what's going on with artificial intelligence. I think there is potentially a dangerous outcome."
He has put his anxieties into some particularly colorful phrases. In August, for instance, Musk tweeted that AI is "potentially more dangerous than nukes." And in October, he said this at a symposium at MIT: "With artificial intelligence, we are summoning the demon. ... You know all those stories where there's the guy with the pentagram and the holy water and he's like... yeah, he's sure he can control the demon, [but] it doesn't work out."
Musk has a kindred spirit in Stephen Hawking. The physicist allowed in May that AI could be the "biggest event in human history," and not necessarily in a good way. A month later, he was telling John Oliver, on HBO's "Last Week Tonight," that "artificial intelligence could be a real danger in the not too distant future." How so? "It could design improvements to itself and outsmart us all."
But Google's Eric Schmidt, is having none of that pessimism. At a summit on innovation in December, the executive chairman of the far-thinking tech titan -- which in October teamed up with Oxford University to speed up research on artificial intelligence -- said that while our worries may be natural, "they're also misguided."