Ceres Excerpt from cnet.com It's a real-life mystery cliffhanger. We've come up with a list of possible reasons a large crater on the biggest object in the asteroid belt looks lit up like a Christmas tree. We could be approachin...
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| Frank Drake, the founder of Search for Extraterrestrial Intelligence (SETI), at his home in Aptos, Calif. (Ramin Rahimian for The Washington Post) |
Excerpt from washingtonpost.com
It was near Green Bank, W.Va., in 1960 that a young radio astronomer named Frank Drake conducted the first extensive search for alien civilizations in deep space. He aimed the 85-foot dish of a radio telescope at two nearby, sun-like stars, tuning to a frequency he thought an alien civilization might use for interstellar communication.
But the stars had nothing to say.
So began SETI, the Search for Extraterrestrial Intelligence, a form of astronomical inquiry that has captured the imaginations of people around the planet but has so far failed to detect a single “hello.” Pick your explanation: They’re not there; they’re too far away; they’re insular and aloof; they’re zoned out on computer games; they’re watching us in mild bemusement and wondering when we’ll grow up.
Now some SETI researchers are pushing a more aggressive agenda: Instead of just listening, we would transmit messages, targeting newly discovered planets orbiting distant stars. Through “active SETI,” we’d boldly announce our presence and try to get the conversation started.
Naturally, this is controversial, because of . . . well, the Klingons. The bad aliens.
NASA discovers first Earth-size planet in habitable zone of another star
"NASA's Kepler Space Telescope has discovered the first validated Earth-size planet orbiting in the habitable zone of a distant star, an area where liquid water might exist on its surface. The planet, Kepler-186f, is ten percent larger in size than Earth and orbits its parent star, Kepler-186, every 130 days. The star, located about 500 light-years from Earth, is classified as an M1 dwarf and is half the size and mass of our sun." (NASA Ames Research Center)
This objection is moot, however, according to the proponents of active SETI. They argue that even if there are unfriendlies out there, they already know about us. That’s because “I Love Lucy” and other TV and radio broadcasts are radiating from Earth at the speed of light. Aliens with advanced instruments could also detect our navigational radar beacons and would see that we’ve illuminated our cities.
“We have already sent signals into space that will alert the aliens to our presence with the transmissions and street lighting of the last 70 years,” Seth Shostak, an astronomer at the SETI Institute in California and a supporter of the more aggressive approach, has written. “These emissions cannot be recalled.”
That’s true only to a point, say the critics of active SETI. They argue that unintentional planetary leakage, such as “I Love Lucy,” is omnidirectional and faint, and much harder to detect than an intentional, narrowly focused signal transmitted at a known planet.
Excerpt from space.com
by Mike Wall
Is it time to take the search for intelligent aliens to the next level?
For more than half a century, scientists have been scanning the heavens for signals generated by intelligent alien life. They haven't found anything conclusive yet, so some researchers are advocating adding an element called "active SETI" (search for extraterrestrial intelligence) — not just listening, but also beaming out transmissions of our own designed to catch aliens' eyes.
Active SETI "may just be the approach that lets us make contact with life beyond Earth," Douglas Vakoch, director of interstellar message composition at the SETI Institute in Mountain View, California, said earlier this month during a panel discussion at the annual meeting of the American Association for the Advancement of Science (AAAS) in San Jose.
Seeking contact
Vakoch envisions using big radio dishes such as the Arecibo Observatory in Puerto Rico to blast powerful, information-laden transmissions at nearby stars, in a series of relatively cheap, small-scale projects.
"Whenever any of the planetary radar folks are doing their asteroid studies, and they have an extra half an hour before or after, there's always a target star readily available that they can shift to without a lot of extra slough time," he said.
The content of any potential active SETI message is a subject of considerable debate. If it were up to astronomer Seth Shostak, Vakoch's SETI Institute colleague, we'd beam the entire Internet out into space.
"It's like sending a lot of hieroglyphics to the 19th century — they [aliens] can figure it out based on the redundancy," Shostak said during the AAAS discussion. "So, I think in terms of messages, we should send everything."
While active SETI could help make humanity's presence known to extrasolar civilizations, the strategy could also aid the more traditional "passive" search for alien intelligence, Shostak added.
"If you're going to run SETI experiments, where you're trying to listen for a putative alien broadcast, it may be very instructive to have to construct a transmitting project," he said. "Because now, you walk a mile in the Klingons' shoes, assuming they have them."
Cause for concern?
But active SETI is a controversial topic. Humanity has been a truly technological civilization for only a few generations; we're less than 60 years removed from launching our first satellite to Earth orbit, for example. So the chances are that any extraterrestrials who pick up our signals would be far more advanced than we are.This likelihood makes some researchers nervous, including famed theoretical physicist Stephen Hawking.
"Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they could reach," Hawking said in 2010 on an episode of "Into the Universe with Stephen Hawking," a TV show that aired on the Discovery Channel. "If so, it makes sense for them to exploit each new planet for material to build more spaceships so they could move on. Who knows what the limits would be?"
Astrophysicist and science fiction author David Brin voiced similar concerns during the AAAS event, saying there's no reason to assume that intelligent aliens would be altruistic.
"This is an area in which discussion is called for," Brin said. "What are the motivations of species that they might carry with them into their advanced forms, that might color their cultures?"
Brin stressed that active SETI shouldn't be done in a piecemeal, ad hoc fashion by small groups of astronomers.
"This is something that should be discussed worldwide, and it should involve our peers in many other specialties, such as history," he said. "The historians would tell us, 'Well, gee, we have some examples of first-contact scenarios between advanced technological civilizations and not-so-advanced technological civilizations.' Gee, how did all of those turn out? Even when they were handled with goodwill, there was still pain."
Out there already
Vakoch and Shostak agreed that international discussion and cooperation are desirable. But Shostak said that achieving any kind of consensus on the topic of active SETI may be difficult. For example, what if polling reveals that 60 percent of people on Earth are in favor of the strategy, while 40 percent are opposed?"Do we then have license to go ahead and transmit?" Shostak said. "That's the problem, I think, with this whole 'let's have some international discussion' [idea], because I don't know what the decision metric is."
Vakoch and Shostak also said that active SETI isn't as big a leap as it may seem at first glance: Our civilization has been beaming signals out into the universe unintentionally for a century, since the radio was invented.
"The reality is that any civilization that has the ability to travel between the stars can already pick up our accidental radio and TV leakage," Vakoch said. "A civilization just 200 to 300 years more advanced than we are could pick up our leakage radiation at a distance of several hundred light-years. So there are no increased dangers of an alien invasion through active SETI."
But Brin disputed this assertion, saying the so-called "barn door excuse" is a myth.
"It is very difficult for advanced civilizations to have picked us up at our noisiest in the 1980s, when we had all these military radars and these big television antennas," he said.
Shostak countered that a fear of alien invasion, if taken too far, could hamper humanity's expansion throughout the solar system, an effort that will probably require the use of high-powered transmissions between farflung outposts.
"Do you want to hamstring all that activity — not for the weekend, not just shut down the radars next week, or active SETI this year, but shut down humanity forever?" Shostak said. "That's a price I'm not willing to pay."
So the discussion and debate continues — and may continue for quite some time.
"This is the only really important scientific field without any subject matter," Brin said. "It's an area in which opinion rules, and everybody has a very fierce opinion."
Photo : NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI Excerpt from sciencetimes.com Originally discovered in 1801 by an astronomer in Sicily, Ceres has had quite an interesting history to date. Originally believed to be a shining star in the sky, when i...
Excerpt from nbcnews.com
By Katie Linendoll
FOUNTAIN HILLS, Ariz. — If words like UFO, extraterrestrial, crops circles and abductee have ever piqued your paranormal interest, do yourself a favor and head to the International UFO Congress.
The annual conference—which holds the Guinness record for being the largest convention dedicated to unidentified flying objects—takes place in the picturesque desert town of Fountain Hills, and this year it ran from Feb. 18 to 22. It's worth noting that Arizona is known as a hotbed of activity when it comes to sightings. Thousands flock to the annual event, which is produced by Open Minds, a paranormal research organization.
Each attendee has his or her own reason for being there. My goal was to find out if modern science and technology have changed the game when it comes to UFO sightings and evidence gathering.
"A lot of people think, go to a UFO convention, it's going to be tinfoil hats, but that's not what this is. We have NASA astrobiologists speak, scientists, high-ranking military officials, the works. I mean, there's a lot of really credible people covering this subject," said UFO Congress co-organizer and paranormal journalist Maureen Elsberry.
Air Force UFO documents now available online
When attending a UFO conference, the best approach is to come in with an open mind, ask lots of questions and talk with people about why they are there. Everyone has a story, from the speakers to the attendees, and even the vendors (some of whom double as ufologists).
The highlight of this year's conference was undeniably the speaker series, and it was standing room only to see one man, Bob Lazar. Lazar first spoke out in 1989, claiming that he'd worked as a government scientist at a secret mountainside facility south of Area 51's main site, where he saw remarkably advanced UFO technology. Critics have sought to discredit Lazar, questioning his employment record and educational credentials.
During the conference, George Knapp, an investigative TV reporter in Las Vegas who broke the Lazar story in '89, led an onstage question-and-answer session with Lazar, who discussed the work he did at a place called S4. Lazar spoke in detail about the alien UFO hangars and UFO propulsion systems he was allegedly asked to reverse engineer, and even loosely sketched them out for the audience.
"All the science fiction had become reality," said Lazar, who was noticeably uncomfortable and clearly surprised by the fact that, decades later, he remains such a draw.
You never know whom you'll bump into at the Congress. In the vendor hall, I met sculptor Alan Groves, who traveled all the way from Australia to peddle his "true to scale" Zetan alien figurines. I wondered if his side gig was lucrative, only to realize he was selling the figures like hotcakes. Then we talked about his day job, and he told me he's worked on special and creature effects for films such as "Star Wars," "Alien," "Labyrinth" and "Jurassic Park."
Many of the attendees told me that hard evidence is a requirement for ufologists and paranormal field experts. Derrel Sims, also known as Alien Hunter, told me he spent two years in the CIA, and also has served as a police officer and licensed private investigator.
He said his first alien encounter happened at age 4, and others in his family have also seen aliens. In 38-plus years of alien research, Sims has learned this: "If you look, the evidence is there." To date, he said, more than 4,000 pieces of that evidence exist.
Sims is adamant about only working with evidence-based methods, using DNA tests and collecting samples as well as relying on ultraviolet, infrared and x-ray tools in his research. He said that, in 1992, he discovered aliens leave their own kind of fluorescent fingerprint, and he continues to test for these clues. He added that if you have had an alien encounter, it's important to react quickly to gather evidence: "fluorescence" stays on the skin for only 24 hours. He said that other marks aliens leave include "scoop" marks, which are an identifying thread some abductees have in common.
Another commonality he's discovered is heritage. He said that, in his research, he has found 45 percent of all abductions happen to Native Americans, Irish and Celtic people, and he said that women also have a higher chance of being abducted.
When it comes to filming hard-to-explain phenomena, Patty Greer, who makes documentaries about crop circles, said that quadcopters — a.k.a. drones — have added production value to her films. Lynne Kitei, who covered a mass UFO sighting in her book and in the documentary The Phoenix Lights, said that even low-tech tools, like the 35mm film she used, are still a reliable way to gather proof of inexplicable flying craft, especially because they offer something an iPhone doesn't: negatives.
White House responds to UFO request
Night vision also offers added opportunities for UFO researchers, according to Ben Hansen, who was the host and lead investigator of SyFy channel's "Fact or Faked: Paranormal Files." He's now the owner of Night Vision Ops, an online store that sells night-vision technology. Hansen said that the consumer accessibility of new military-grade technologies in thermal and light amplification scopes are upping the game for the everyday UFO enthusiast.
To close out an intense few days on site at the Congress, Hansen's team invited me to a night watch near Arizona's Superstition Mountains. It was fascinating to see the latest optics add incredible clarity to the night sky, amplifying available light up to 50,000 times beyond what the unaided eye can see. Using the right technology, we were also able to see that a certain flying object, which made everyone nearby jump, wasn't a UFO after all. It was a bat.
I was surrounded by some serious tech all weekend, and it was eye-opening to see the ways that UFO hunters are gathering scientific evidence to learn more about the paranormal world. But I have to say, the gadget that was the most useful to me at the conference was my iPhone, which I used to download a free nightlight app for kids. For the few hours I managed to sleep, it was with the soothing illumination provided by "Kiwi the Green Koala." In short, I was officially freaked out.
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| The God Particle, which is believed to be responsible for all the mass in the universe, was discovered in 2012 using a Cern's supercollider. In this image two high-energy photons collide. The yellow lines are the measured tracks of other particles produced in the collision, which helped lead to the discovery of the God particle. |
Excerpt from dailymail.co.uk
- God Particle is believed to be responsible for all the mass in the universe
- Particle was discovered in 2012 using a Cern's supercollider in Geneva
- uperconductor experiment suggests the particle could be detected without the huge amounts of energy used at by the Large Hadron Collider
- LHC is due to come back online next month after an upgrade that has given it a big boost in energy
Scientists have discovered a simulated version of the elusive 'God particle' using superconductors.
The God Particle, which is believed to be responsible for all the mass in the universe, was discovered in 2012 using a Cern's supercollider.
The superconductor experiment suggests that the Higgs particle could be detected without the huge amounts of energy used at by the Large Hadron Collider.
The results could help scientists better understand how this mysterious particle – also known as the Higgs boson – behaves in different conditions.
'Just as the Cern experiments revealed the existence of the Higgs boson in a high-energy accelerator environment, we have now revealed a Higgs boson analogue in superconductors,' said researcher Aviad Frydman from Bar-Ilan University.
Superconductors are a type of metal that, when cooled to low temperatures, allow electrons to pass through freely.
'The Higgs mode was never actually observed in superconductors because of technical difficulties - difficulties that we've managed to overcome,' Professor Frydman said.
The superconductor experiment suggests that the Higgs particle could be detected without the huge amounts of energy used at by the Large Hadron Collider (pictured)
WHAT IS THE GOD PARTICLE?
The 'God Particle', also known as the Higgs boson, was a missing piece in the jigsaw for physicists in trying to understand how the universe works.
Scientists believe that a fraction of a second after the Big Bang that gave birth to the universe, an invisible energy field, called the Higgs field, formed.
This has been described as a kind of 'cosmic treacle' across the universe.
As particles passed through it, they picked up mass, giving them size and shape and allowing them to form the atoms that make up you, everything around you and everything in the universe.
This was the theory proposed in 1964 by former grammar school boy Professor Higgs that has now been confirmed.
Without the Higgs field particles would simply whizz around space in the same way as light does.
A boson is a type of sub-atomic particle. Every energy field has a specific particle that governs its interaction with what's around it.
To try to pin it down, scientists at the Large Hadron Collider near Geneva smashed together beams of protons – the 'hearts of atoms' – at close to the speed of light, recreating conditions that existed a fraction of a second after the Big Bang.
Although they would rapidly decay, they should have left a recognisable footprint. This footprint was found in 2012.
The main difficulty was that the superconducting material would decay into something known as particle-hole pairs.
Large amounts of energy – which are usually needed to excite the Higgs mode - tend to break apart the electron pairs that act as the material's charge.
Professor Frydman and his colleagues solved this problem by using ultra-thin superconducting films of Niobium Nitrite (NbN) and Indium Oxide (InO) as something known as the 'superconductor-insulator critical point.'
This is a state in which recent theory predicted the decay of the Higgs would no longer occur.
In this way, they could still excite a Higgs mode even at relatively low energies.
'The parallel phenomenon in superconductors occurs on a different energy scale entirely - just one-thousandth of a single electronvolt,' Professor Frydman added.
'What's exciting is to see how, even in these highly disparate systems, the same fundamental physics is at work.'
The different approach help solve one of the longstanding mysteries of fundamental physics.
The discovery of the Higgs boson verified the Standard Model, which predicted that particles gain mass by passing through a field that slows down their movement through the vacuum of space.
To try to pin it down, scientists at the Large Hadron Collider near Geneva smashed together beams of protons – the 'hearts of atoms' – at close to the speed of light, recreating conditions that existed a fraction of a second after the Big Bang.
Although they would rapidly decay, the also left a recognisable footprint.
Professor Higgs, 83, has been waiting since 1964 for science to catch up with his ideas about the Higgs boson
According to Professor Frydman, observation of the Higgs mechanism in superconductors is significant because it reveals how a single type of physical process behaves under different energy conditions.
'Exciting the Higgs mode in a particle accelerator requires enormous energy levels - measured in giga-electronvolts, or 109 eV,' Professor Frydman says.
'The parallel phenomenon in superconductors occurs on a different energy scale entirely - just one-thousandth of a single electronvolt.
'What's exciting is to see how, even in these highly disparate systems, the same fundamental physics is at work.'
The LHC is due to come back online in March after an upgrade that has given it a big boost in energy.
'With this new energy level, the (collider) will open new horizons for physics and for future discoveries,' CERN Director General Rolf Heuer said in a statement.
'I'm looking forward to seeing what nature has in store for us.'
Cern's collider is buried in a 27-km (17-mile) tunnel straddling the Franco-Swiss border at the foot of the Jura mountains.
The LHC in Geneva will come back online in March after an upgrade that has given it a big boost in energy
Excerpt from latimes.com
Computers have beaten humans at chess and "Jeopardy!," and now they can master old Atari games such as "Space Invaders" or "Breakout" without knowing anything about their rules or strategies.
Playing Atari 2600 games from the 1980s may seem a bit "Back to the Future," but researchers with Google's DeepMind project say they have taken a small but crucial step toward a general learning machine that can mimic the way human brains learn from new experience.
Unlike the Watson and Deep Blue computers that beat "Jeopardy!" and chess champions with intensive programming specific to those games, the Deep-Q Network built its winning strategies from keystrokes up, through trial and error and constant reprocessing of feedback to find winning strategies.
“The ultimate goal is to build smart, general-purpose [learning] machines. We’re many decades off from doing that," said artificial intelligence researcher Demis Hassabis, coauthor of the study published online Wednesday in the journal Nature. "But I do think this is the first significant rung of the ladder that we’re on."
The Deep-Q Network computer, developed by the London-based Google DeepMind, played 49 old-school Atari games, scoring "at or better than human level," on 29 of them, according to the study.
The algorithm approach, based loosely on the architecture of human neural networks, could eventually be applied to any complex and multidimensional task requiring a series of decisions, according to the researchers.
The algorithms employed in this type of machine learning depart strongly from approaches that rely on a computer's ability to weigh stunning amounts of inputs and outcomes and choose programmed models to "explain" the data. Those approaches, known as supervised learning, required artful tailoring of algorithms around specific problems, such as a chess game.
The computer instead relies on random exploration of keystrokes bolstered by human-like reinforcement learning, where a reward essentially takes the place of such supervision.
“In supervised learning, there’s a teacher that says what the right answer was," said study coauthor David Silver. "In reinforcement learning, there is no teacher. No one says what the right action was, and the system needs to discover by trial and error what the correct action or sequence of actions was that led to the best possible desired outcome.”
The computer "learned" over the course of several weeks of training, in hundreds of trials, based only on the video pixels of the game -- the equivalent of a human looking at screens and manipulating a cursor without reading any instructions, according to the study.
Over the course of that training, the computer built up progressively more abstract representations of the data in ways similar to human neural networks, according to the study.
There was nothing about the learning algorithms, however, that was specific to Atari, or to video games for that matter, the researchers said.
The computer eventually figured out such insider gaming strategies as carving a tunnel through the bricks in "Breakout" to reach the back of the wall. And it found a few tricks that were unknown to the programmers, such as keeping a submarine hovering just below the surface of the ocean in "Seaquest."
The computer's limits, however, became evident in the games at which it failed, sometimes spectacularly. It was miserable at "Montezuma's Revenge," and performed nearly as poorly at "Ms. Pac-Man." That's because those games also require more sophisticated exploration, planning and complex route-finding, said coauthor Volodymyr Mnih.
And though the computer may be able to match the video-gaming proficiency of a 1980s teenager, its overall "intelligence" hardly reaches that of a pre-verbal toddler. It cannot build conceptual or abstract knowledge, doesn't find novel solutions and can get stuck trying to exploit its accumulated knowledge rather than abandoning it and resort to random exploration, as humans do.
“It’s mastering and understanding the construction of these games, but we wouldn’t say yet that it’s building conceptual knowledge, or abstract knowledge," said Hassabis.
The researchers chose the Atari 2600 platform in part because it offered an engineering sweet spot -- not too easy and not too hard. They plan to move into the 1990s, toward 3-D games involving complex environments, such as the "Grand Theft Auto" franchise. That milestone could come within five years, said Hassabis.
“With a few tweaks, it should be able to drive a real car,” Hassabis said.
DeepMind was formed in 2010 by Hassabis, Shane Legg and Mustafa Suleyman, and received funding from Tesla Motors' Elon Musk and Facebook investor Peter Thiel, among others. It was purchased by Google last year, for a reported $650 million.
Hassabis, a chess prodigy and game designer, met Legg, an algorithm specialist, while studying at the Gatsby Computational Neuroscience Unit at University College, London. Suleyman, an entrepreneur who dropped out of Oxford University, is a partner in Reos, a conflict-resolution consulting group.
Scholz's star - shown in this artist's impression - is currently 20 light-years away. But it once came much closerExcerpt from bbc.comAn alien star passed through our Solar System just 70,000 years ago, astronomers have discovered. No othe...
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| These two views of Ceres were acquired by NASA’s Dawn spacecraft on Feb. 12, 2015, from a distance of about 52,000 miles (83,000 kilometers) as the dwarf planet rotated. The images, which were taken about 10 hours apart, have been magnified from their original size. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA |
Excerpt from spaceflightnow.com
Images from NASA’s Dawn spacecraft on approach to the dwarf planet Ceres show a world pockmarked by craters and mysterious bright spots, and scientists are eager for a better look in the weeks ahead.
The latest images were taken Feb. 12 at a distance of 52,000 miles, or 83,000 kilometers, from Ceres. NASA released the fresh views Tuesday.
Every picture taken of Ceres in the coming weeks will show greater detail, as Dawn is set to be captured by the Texas-sized world’s gravity March 6. The dwarf planet will pull Dawn into the first of a series of survey orbits 8,400 miles from Ceres around April 23.
The imagery so far reveals Ceres as a cratered world, and Dawn will make a global map of the dwarf planet during its time in orbit.
But several bright spots have captured the attention of scientists.
“As we slowly approach the stage, our eyes transfixed on Ceres and her planetary dance, we find she has beguiled us but left us none the wiser,” said Chris Russell, principal investigator of the Dawn mission, based at UCLA. “We expected to be surprised; we did not expect to be this puzzled.”
The suspense is compounded by Dawn’s slow rate of approach. The probe’s ion propulsion system is gradually nudging Dawn on a trajectory closer to Ceres, eventually moving the spacecraft close enough to be grasped by the 590-mile diameter dwarf planet’s gravity.
“I want to know what is causing the bright spots,” Russell wrote in an email to Spaceflight Now. “The increased resolution seems to have moved us no closer to answering this mystery. I am frustrated by the suspense. This is the one problem of ion propulsion: We are closing in on Ceres very slowly.”
The latest photos have a resolution have 4.9 miles, or 7.8 kilometers, per pixel, according to a NASA press release.
Dawn’s framing camera will take its next set of images Feb. 20 at a range of about 30,000 miles. After late February, the resolution of Dawn’s imagery will be reduced as the spacecraft passes Ceres and flies in front of it, before being pulled closer in early April for insertion into orbit.
Soon after arriving in April, the spacecraft’s instruments will look for the signature of water vapor plumes shooting into space from the surface of Ceres, which may be blanketed in a crust of ice.
Dawn will orbit closest to Ceres in December at an altitude of 232 miles.
Dawn’s mission planners say the spacecraft could operate around Ceres until late 2016.
Ceres is the second destination for NASA’s Dawn mission, which launched in September 2007 and visited asteroid Vesta in 2011 and 2012.
Excerpt from americanlivewire.com
A low-mass red dwarf star passed through the outer Oort Cloud 70,000 years back in the closest approach made by any star into our system, discovers a team of researchers from various countries.
Lying in the constellation Monoceros and known as Scholtz’s star, it is a part of a binary system and has 8% the mass of the sun. Its companion, a brown dwarf, is said to have 6%.
The lowest end of the stellar spectrum, brown dwarfs are larger than gas giants but not as much so as to sustain hydrogen fusion for a larger period of time.
Due to its faint appearance, Scholtz’s star was discovered only a year ago by astronomer Ralf Dieter-Scholz in Potsdam, Germany, through the use of NASA’s WISE (Wide Field Infrared Survey Explorer), which mapped the entire sky in infrared during the years 2010 and 2011.
At the same time, the radial velocity of the star depicted that it was moving away from the solar system much faster than expected.
These motions led the researchers to conclude that either the star is headed toward our system, or moving away from it.
After analyzing the data, Mamajek concluded, “…The radial velocity measurements were consistent with it running away from the Sun’s vicinity–and we realized it must have had a close flyby in the past.”
Through the use of computer models, it was seen that the star passed about 5 trillion miles from our solar system around 70,000 years ago.
Mamajek and his team are 98 percent certain Scholtz’s star traveled through the outer Oort Cloud.
Although Scholtz’s star is 10th magnitude, too dim to be seen with the naked eye, it is magnetically active, which can cause it to flare at times and become significantly brighter. If this happened during its close approach to our solar system, prehistoric humans might have actually seen it.
The researchers published their findings in Astrophysical Journal Letters.
The lowest end of the stellar spectrum, brown dwarfs are larger than gas giants but not as much so as to sustain hydrogen fusion for a larger period of time.
Due to its faint appearance, Scholtz’s star was discovered only a year ago by astronomer Ralf Dieter-Scholz in Potsdam, Germany, through the use of NASA’s WISE (Wide Field Infrared Survey Explorer), which mapped the entire sky in infrared during the years 2010 and 2011.
At the same time, the radial velocity of the star depicted that it was moving away from the solar system much faster than expected.
These motions led the researchers to conclude that either the star is headed toward our system, or moving away from it.
After analyzing the data, Mamajek concluded, “…The radial velocity measurements were consistent with it running away from the Sun’s vicinity–and we realized it must have had a close flyby in the past.”
Through the use of computer models, it was seen that the star passed about 5 trillion miles from our solar system around 70,000 years ago.
Mamajek and his team are 98 percent certain Scholtz’s star traveled through the outer Oort Cloud.
Although Scholtz’s star is 10th magnitude, too dim to be seen with the naked eye, it is magnetically active, which can cause it to flare at times and become significantly brighter. If this happened during its close approach to our solar system, prehistoric humans might have actually seen it.
The researchers published their findings in Astrophysical Journal Letters.
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| 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.
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.”
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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