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What astronomers learned when Messenger space probe crashed into Mercury

May 8, 2015 / / 0 Comments



Excerpt from statecolumn.com


On April 30, NASA concluded an historic voyage known as the Mercury Surface, Space Environment, Geochemistry and Ranging mission. The mission came to an end when the spacecraft carrying analytical instruments, Messenger, crashed into the planet’s surface after consuming all of its fuel.
The mission was far from a waste, however, as NASA rarely expects to see the majority of the spacecraft they launch ever again. According to Discovery, The probe sent back a spectacular photo of the surface of Mercury, using the craft’s Narrow Angle Camera in tandem with the Mercury Dual Imaging System. The photo shows a mile-wide view of the nearby planet’s surface in 2.1 meters per pixel resolution.
Right after the probe delivered the photo to NASA’s Deep Space Network, which is a collection of global radio antennae that tracks data on the agency’s robotic missions around the solar system, the signal was lost in what scientists assume was the craft’s final contact with the closest planet to the sun.
The four-year mission came to an end when the craft could no longer maintain its orbit around the solar system’s innermost planet due to lack of fuel. Mercury is just 36 miles from the sun, compared to Earth, which is 93 million miles away from the center of the solar system. Mercury is a peculiar world, with both frigid and extremely hot temperatures. Messenger also revealed that Mercury has a magnetic field similar to that of Earth’s, created by the motion of metallic fluids within the planet’s core.
The main challenge the Messenger mission faced was getting the space probe into orbit around Mercury. Due to the planet’s proximity to the sun, it was extremely difficult for flight engineers to avoid its gravitational pull. In addition to the challenge of catching Mercury’s comparatively weak gravitational force, high temperatures also made things tricky. Messenger was equipped with a sunshield designed to protect the spaceship cool on the side that faced the sun. NASA engineers also attempted to chart a long, elliptical orbit around Mercury, giving Messenger time to cool off as it rounded the backside of the planet.
Messenger made over 4,000 orbits around Mercury between 2011 and 2015, many more than the originally planned one-year mission would allow.
With the close-up shots of Mercury’s surface provided by Messenger, NASA scientists were able to detect trace signals of magnetic activity in Mercury’s crust. Using clues from the number of impact craters on the surface, scientists figured that Mercury’s magnetized regions could be as old as 3.7 billion years. Astronomers count the craters on a planet in order to estimate its age – the logic being that younger surfaces should have fewer impact sites than older surfaces.
The data sent back by Messenger has caused astronomers to reconsider their understanding of Mercury’s magnetic history. They now date the beginning of magnetism on Mercury to about 700 million years after the planet was formed. They cannot say for sure, however, if the magnetic field has been consistently active over this timeframe.
According to Messenger guest investigator Catherine Johnson, geophysicist at the University of British Columbia in Vancouver, that it was possible the magnetic field has been active under constant conditions, though she suspects it might also oscillate over time, like Earth’s. Information for the time period between 4 billion years ago and present day is sparse, though Johnson added that additional research is in the pipeline.
Johnson was pleased, however, with the insight offered into Mercury’s formation provided by these new magnetic clues. Magnetism on a planetary scale typically indicates a liquid metal interior. Since Mercury is so tiny, scientists originally believed that its center would be solid, due to the rate of cooling. The presence of liquid in the planet’s center suggests other materials’ presence, which would lower the freezing point. This suggests that a totally solid core would be unlikely.
Mercury’s magnetic field offers valuable insight into the formation of the planet, the solar system, and even the universe. Magnetism on Mercury indicates that it has a liquid iron core, according to Messenger lead scientist Sean Solomon of Columbia University.

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Desperately Seeking ET: Fermi’s Paradox Turns 65 ~ Part 2

May 5, 2015 / / 0 Comments

Excerpt from huffingtonpost.comIntroductionWhy is it so hard to find ET? After 50 years of searching, the SETI project has so far found nothing. In the latest development, on April 14, 2015 Penn State researchers announced that after searching through...

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Desperately Seeking Extraterrestrials ~ Fermi’s Paradox Turns 65 ~ Part 1

May 4, 2015 / / 0 Comments

Excerpt from huffingtonpost.comIntroduction 65 years ago, in 1950, while having lunch with colleagues Edward Teller and Herbert York, Nobel physicist Enrico Fermi suddenly blurted out, "Where is everybody?" His question is now known as Fermi's p...

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Jane Goodall Says SeaWorld ‘Should Be Closed Down’

May 1, 2015 / / 0 Comments

Jane Goodall


Excerpt from huffingtonpost.com

NEW YORK -- Jane Goodall wants to see SeaWorld go extinct.
The 81-year-old primatologist said whales and dolphins should never be held in captivity, and that the entertainment company known for its orca shows should be shuttered.

“They definitely should be closed down,” Goodall said in an interview with The Huffington Post earlier this month. 

She’s not alone. SeaWorld’s stock price has been plummeting since July 2013, when CNN released the documentary “Blackfish." The film exposed the misery endured by SeaWorld's trained orca and the dangers posed to trainers working with stressed-out carnivorous whales. 

seaworld stock
SeaWorld's stock price has declined precipitously since the 2013 release of "Blackfish."

One of the problems highlighted in "Blackfish" is that cetacea, the family of aquatic mammals that includes whales, dolphins and porpoises, communicate with sonar-like sound waves. When confined to tanks, Goodall noted, those waves echo back and create a hellish cacophony for the animals.

“When they are contained in these tanks … that is acoustical hell,” said Goodall, adding that her nonprofit organization, the Jane Goodall Institute, is urging aquariums across the country to free their whales. “The sounds bounce back from the walls of the tank.”

SeaWorld aggressively refuted many of the film's claims, including allegations that its whales were unhealthy and that the company tried to cover up details surrounding the 2010 death of trainer Dawn Brancheau, who was mauled by an orca. 

After the release of "Blackfish," SeaWorld saw a rapid decline in visitors, and with that, in the price of shares. But on Monday, Goldman Sachs upgraded the stock, optimistic that the company can retool its image as consumers start forgetting about the blockbuster documentary.

"Jane Goodall is a respected scientist and advocate for the world’s primates, but we couldn’t disagree more with her on this," Becca Bides, a SeaWorld spokeswoman, said in an emailed statement. 

"Zoos and marine mammal parks like SeaWorld allow people to experience animals in a way that is inspiring and educational."
Asked about the allegation that SeaWorld's tanks are detrimental to whales, Bides denied the claim, arguing that they are specially crafted to keep underwater noise levels quieter than the ambient ocean.

As of last December, SeaWorld held 22 orcas in its three U.S. marine parks, five of which were caught in the wild, according to the nonprofit advocacy group Whale and Dolphin Conservation. A total of 57 orcas are held in captivity around the world, the group notes. At least 160 orcas have died in captivity since 1961, and an additional 30 pregnant whales have miscarried or had stillborn calves.

Goodall said she remains hopeful that humans are gaining a greater sense of empathy for animals and losing interest in watching them perform for entertainment.

“It’s not only that they’re really big, highly intelligent and social animals so that the capture and confinement in itself is cruel,” she said of the captive orcas, but also that “they have emotions like ours.”
She welcomed the decision by Ringling Bros. and Barnum & Bailey Circus to eliminate elephants in its shows by 2018.

“If you see what happens to those baby elephants, the way they’re trained, it’s absolutely chilling,” said Goodall, who had a pendant in the shape of Africa hanging from her necklace. “They lose all of their young elephant playfulness, and then they can be trained.”

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The Messenger of fate: NASA spacecraft smashes into planet Mercury

April 30, 2015 / / 0 Comments

Excerpt from usatoday.comIts fuel tanks empty and its options gone, NASA's Messenger spacecraft smashed into planet Mercury on Thursday afternoon after valiantly fighting off the inevitable.Engineers calculated that the spacecraft, traveling a scorc...

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Astrophysicists create most complete 3-D map of the universe

April 28, 2015 / / 0 Comments






Excerpt from thespacereporter.com


A team of scientists has created a detailed map of our cosmic “neighborhood” extending nearly two billion lights years in every direction. This 3-D map showing galaxies in their superclusters will aid astrophysicists in better understanding how matter, including dark matter, is distributed in the universe.

According to a Science Daily report, the map indicates the relative concentration of galaxies in different areas, including the largest nearby supercluster called the Shapely Concentration, as well as less explored areas. The scientists found no sign of any pattern in the distribution of matter.

“The galaxy distribution isn’t uniform and has no pattern. It has peaks and valleys much like a mountain range. This is what we expect if the large-scale structure originates from quantum fluctuations in the early universe,” Mike Hudson of the University of Waterloo said in a statement.

 

The researchers hope that a more complete view of the placement and movement of matter will aid in forming predictions about the expansion of the universe. In particular, the team hopes to gain insight into the phenomenon of peculiar velocity – the differences in galactic movement caused by the unevenness in the expansion of the universe. It is thought that the non-uniform movement of galaxies is influenced by dark matter – a form of matter only indirectly detectable through its gravitational influence on light and visible matter.


A cross-section of the cosmic map detailing accumulations of massive clusters. The dark red region is the famous Shapley Concentration, the largest collection of galaxies in the nearby universe.
Hudson et al./University of Waterloo








“A better understanding of dark matter is central to understanding the formation of galaxies and the structures they live in, such as galaxy clusters, superclusters and voids,” said Hudson.

The team plans to continue expanding and detailing the map in collaboration with additional researchers. The team’s work was published in the journal Monthly Notices of the Royal Astronomical Society.

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Is In-Flight Refueling Coming to Commercial Airlines?

April 12, 2015 / / 0 Comments




Excerpt from space.com

 This article was originally published on The Conversation. The publication contributed this article to Space.com's Expert Voices: Op-Ed & Insights.

There’s real pressure on the aviation industry to introduce faster, cheaper and greener aircraft, while maintaining the high safety standards demanded of airlines worldwide.

Airlines carry more than three billion passengers each year, which presents an enormous challenge not only for aircraft manufacturers but for the civil aviation infrastructure that makes this extraordinary annual mass-migration possible. Many international airports are close to or already at capacity. The International Air Transport Association (IATA) has estimated that, without intervention, many global airports – including major hubs such as London Heathrow, Amsterdam Schiphol, Beijing and Dubai – will have run out of runway or terminal capacity by 2020. 


The obvious approach to tackling this problem is to extend and enlarge airport runways and terminals – such as the long-proposed third runway at London Heathrow. However there may be other less conventional alternatives, such as introducing in-flight refuelling for civil aircraft on key long-haul routes. Our project, Research on a Cruiser-Enabled Air Transport Environment (Recreate), began in 2011 to evaluate whether this was something that could prove a viable, and far cheaper, solution.

If in-flight refuelling seems implausible, it’s worth remembering that it was first trialed in the 1920s, and the military has continued to develop the technology ever since. The appeal is partly to reduce the aircraft’s weight on take-off, allowing it to carry additional payload, and partly to extend its flight range. Notably, during the Falklands War in 1982 RAF Vulcan bombers used in-flight refuelling to stage what was at the time the longest bombing mission ever, flying 8,000 miles non-stop from Ascension Island in the South Atlantic to the Falklands and back.

Reducing take-off weight could offer many benefits for civilian aircraft too. Without the need to carry so much fuel the aircraft can be smaller, which means less noise on take-off and landing and shorter runways. This opens up the network of smaller regional airports as new potential sites for long-haul routes, relieving pressure on the major hubs that are straining at the seams.

There are environmental benefits too, as a smaller, lighter aircraft requires less fuel to reach its destination. Our initial estimates from air traffic simulations demonstrate that it’s possible to reduce fuel burn by up to 11% over today’s technology by simply replacing existing global long-haul flight routes with specifically designed 250-seater aircraft with a range of 6,000nm after one refuelling – roughly the distance from London to Hong Kong. This saving could potentially grow to 23% with further efficiencies, all while carrying the same number of passengers the same distance as is possible with the current aircraft fleet, and despite the additional fuel burn of the tanker aircraft.

Tornado fighter jets in-flight refuel
Imagine if these Tornado fighter jets were 250-seater passenger aircraft and you’ve got the idea.

However, this is not the whole picture – in-flight refuelling will require the aerial equivalent of petrol stations in order to deliver keep passenger aircraft in the sky. With so much traffic it simply wouldn’t be possible to refuel any aircraft any time, anywhere it was needed. The location of these refuelling zones, coupled with the flight distance between the origin and destination airports can greatly affect the potential benefits achievable, possibly pulling flights away from their shortest route, and even making refuelling on some routes impossible – if for example the deviation to the nearest refuelling zone meant burning as much fuel as would have been saved.

Safety and automation

As with all new concepts – particularly those that involve bringing one aircraft packed with people and another full of fuel into close proximity during flight – it’s quite right to ask whether this is safe. To try and answer this question, the Dutch National Aerospace Laboratory and German Aerospace Centre used their flight simulators to test the automated in-flight refuelling flight control system developed as part of the Recreate project.

One simulator replicated the manoeuvre from the point of view of the tanker equipped with an in-flight refuelling boom, the other simulated the aircraft being refuelled mid-flight. Critical test situations such as engine failure, high air turbulence and gusts of wind were simulated with real flight crews to assess the potential danger to the operation. The results were encouraging, demonstrating that the manoeuvre doesn’t place an excessive workload on the pilots, and that the concept is viable from a human as well as a technical perspective.

So far we’ve demonstrated the potential aerial refuelling holds for civilian aviation, but putting it into practice would still pose challenges. Refuelling hubs would need to be established worldwide, shared between airlines. There would need to be fundamental changes to airline pilot training, alongside a wider public acceptance of this departure from traditional flight operations.

However, it does demonstrate that, in addition to all the high-tech work going into designing new aircraft, new materials, new engines and new fuels, the technology we already have offers solutions to the long-term problems of ferrying billions of passengers by air around the world.

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How the Secession Movement Could Break Up the U.S.

April 9, 2015 / / 0 Comments



new U.S. map
Excerpt from charismanews.com  
A new map of the U.S. could include a state called Jefferson, made up of Northern California and Southern Oregon, a new state called Western Maryland and a new state called North Colorado. (CBN)

If you mention the word secession most people think of the South during the Civil War. But today, a new movement is gaining steam because of frustration over a growing, out-of-control federal government.
A number of conservative, rural Americans are taking about seceding and creating their own states, meaning a new map of the United States of America could include the following:
  • A 51st state called Jefferson, made up of Northern California and Southern Oregon
  • A new state called Western Maryland
  • A new state called North Colorado
These are real movements gaining traction with voters across the country. Jeffrey Hare runs the 51st State Initiative in Colorado, an effort to fight an out-of-control legislature trying to ram big government policies down the throats of voters.
"We're at this point of irreconcilable differences," Hare told CBN News.





Secessionist talk has filled town hall meetings and the divide discussed is not just ideological.
"It's predominately left versus right, but it's urban versus rural because you typically find more typical conservative values in rural America," Hare said.
An Attack on Colorado?
That's the crux of the issue. Rural Americans across many states feel they're not being heard. Their laundry list is long and at the top of that list are stricter gun control laws.
According to Weld County, Colo., Sheriff John Cooke, the state legislature is out of control.
"They are out of touch with rural Colorado," he said. "There is an attack on rural Colorado and it's not just on gun control laws. It's on several of the other bills that they passed."
Government mandates on renewable energy, environmental policies restricting oil and gas drilling, and controversial social issues like gay marriage have also led to this divide and talk of secession.
Organizers want to create "North Colorado," an idea that went to voters in 11 counties this past fall. But not everyone in Colorado thinks secession is a great idea.
"I don't think that's necessarily the way to make something happen within the area you live," Colorado resident Greg Howe told CBN News. "You're supposed to work within our electoral services."
The so-called secession movement in Colorado had mixed results this past November. Some counties approved it. Others didn't.
But the organizers of the 51st State Initiative are undaunted, saying this type of movement takes time.
"Movements take a while; education takes time," Hare said. "People do have a hard time saying ,'I want to live in a different state,' even though physically they live in the same house."
"It's hard for them since their lives have been Coloradoans," he explained. "Their whole lives to say that 'I'm going to be a new Coloradoan' or 'I want to live in the state of liberty' or something different."
An 'Amicable' Divorce
That desire for something different can also be felt in Arizona, Michigan, and in Western Maryland where thousands have signed secession petitions.
One website reads, "We intend to exercise our right of self-determination and self-governance to better secure our rights to life, liberty, and the pursuit of happiness."

Scott Strzelczyk, the leader of the Western Maryland movement, is ready to get going.
"If they are not going to listen or take our needs into consideration and govern in a way that's more in accordance with the way we want to be governed we are seeking an amicable divorce," he said.
Meanwhile, in Northern California and Southern Oregon, activists want to come together in the state of "Jefferson."
Their proposed state flag includes two "Xs," representing their feeling of being double-crossed by the state capitals of Sacramento, Calif., and Salem, Ore.
No Small Task
Creating a new state isn't easy. The last time a state actually gave up territory was in 1820, when Maine split from Massachusetts. Since then, additional efforts have been unsuccessful. 
The first step is getting it passed by the state legislature and then the U.S. Congress.
"This is a valid constitutional process that our founding fathers specifically wrote into the Constitution," Hare said. "Well, if they didn't write this into the Constitution to be used, then why did they write it in?"
But supporters have an uphill battle since the media will not be their friend.
"The danger is once the outside media start to grab hold of it, the attention is on the difficulty, the almost impossibility of it happening," professor Derek Everett, with Metropolitan State University in Denver, explained.
Voter 'Disconnect'
State secession proponents, like Roni Bell Sylvester of Colorado, say they will keep fighting because the dismissive attitude of state legislative bodies must end.
"I find the sort of arrogant, dismissive to be further proof as to just how disconnected the urban is from the rural," Sylvester said.
Movements like the one in Colorado and other states could be just the beginning—at least that's the talk at town hall meetings in places like Colorado and elsewhere.
It's called 'voter disconnect" where the people say they've had enough and are crying out for something to be done.
"We, at some point, have to figure out a way to get our point across or at least be able to have a dialogue and not be ignored because you haven't seen anything yet over the next 5 to 10 years," one resident warned at a recent town hall meeting in Colorado.
As for Hare, he said it boils down to one simple concept.
"I think ultimately what people want, whether you look at it from a right or left paradigm, is government to stay out of their business," he said.

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Why Luke Skywalker’s binary sunset may be real after all

March 30, 2015 / / 0 Comments






Excerpt from csmonitor.com

Researchers have found Jupiter-scale gas giants orbiting binary stars and estimate that Earth-like planets orbiting binary stars could be as numerous as rocky planets orbiting single-star systems.


For all the sci-fi charm of watching a pair of suns sink below a distant horizon on a planet in a galaxy far, far away, conventional wisdom has held that binary-star systems can't host Earth-scale rocky planets.

As the two stars orbit each other like square-dance partners swinging arm in arm, regular variations in their gravitational tug would disrupt planet formation at the relatively close distances where rocky planets tend to appear.

Not so fast, say two astrophysicists. They argue that only are Tatooine-like planets likely to be out there. They could be as numerous as rocky planets orbiting single-star systems – which is to say, there could be large number of them.

Building rocky planets in a binary system not only is possible, it's "not even that hard," says Scott Kenyon, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., who along with University of Utah astrophysicist Benjamin Bromley performed the calculations.
Researchers have found Jupiter-scale gas giants orbiting binary stars and have estimated that such gas giants are likely to be as common in binary systems as they are in systems with a single star.
"If that's true, then Earth-like planets around binaries are just as common as Earth-like planets around single stars," Dr. Kenyon says. "If they're not common, that tells you something about how they form or how they interact with the star over billions of years."

The modeling study grew out of work the two researchers were undertaking to figure out how the dwarf planet Pluto and its largest moon Charon manage to share space with four smaller moons that orbit the two larger objects. 

Pluto and Charon form a binary system that early in its history saw the two objects graze each other to generate a ring of dust that would become the additional moons.

The gravity the surrounding dust felt as Pluto and Charon swung about their shared center of mass would vary with clock-like precision.

Conventional wisdom held that this variable tug would trigger collisions at speeds too fast to allow the dust and larger chunks to merge into ever larger objects.

Kenyon and Dr. Bromley found that, in fact, the velocities would be smaller than people thought – no greater than the speeds would be around a single central object, where velocities are slow enough to allow the debris to bump gently and merge to build ever-larger objects.

They recognized that binary stars hosting planets are essentially scaled-up versions of the Pluto-Charon system. So they applied their calculations to a hypothetical binary star system with a circumstellar disk of dust and debris.

"The modest jostling in these orbits is the same modest jostling you'd get around a single star," Kenyon says, allowing rocky inner planets to form.

As for the Jupiter- or Neptune-scale planets found around binary stars, they would have formed farther out and migrated in over time, the researchers say, since there is too little material within the inner reaches of a circumstellar disk to build giant planets.

The duo's calculations imply that as more planets are discovered orbiting binary stars, a rising number of Tatooines will be among them. 

Tatooine "was science fiction," Kenyon says. But "it's not so far from science reality."

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Black Holes, the Large Hadron Collider, & Finding Parallel Universes

March 27, 2015 / / 0 Comments

Excerpt from huffingtonpost.comI am a huge science enthusiast and an unabashed science fiction fan. There are tons of really cool stories out there that fire the imagination and even inspire young people to go into science. (I know they did me.) ...

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Bird Thought To Be Extinct Resurfaces In Myanmar

March 6, 2015 / / 0 Comments

Jerdon's BabblerExcerpt from techtimes.comJerdon's Babbler is a species of bird that was believed to be extinct until this species unexpectedly resurfaced in Myanmar. This brown and white bird is roughly the size of a house sparrow.The bird was last ...

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Windwheel concept combines tourist attraction with "silent turbine"

February 26, 2015 / / 0 Comments


 The Dutch Windwheel concept is designed to be part energy icon, part tourist attraction an...


Excerpt from gizmag.com
By Stu Robarts


The Dutch have long used windmills to harness wind energy. A new concept proposed for city of Rotterdam, however, is surely one of the most elaborate windmills ever conceived. The Dutch Windwheel is a huge circular wind energy converter that houses apartments, a hotel and a giant coaster ride.

The concept is designed to be part energy icon, part tourist attraction and part residential building. It is a 174-m (571-ft) structure comprising two huge rings that appear to lean against each other. "We wanted to combine a big attraction for Rotterdam with a state-of-the-art sustainable concept," explains Lennart Graaff of the Dutch Windwheel Corporation, to Gizmag.

The larger outer ring houses 40 pods on rails that move around the ring and provide those who visit with views of Rotterdam and its port. The smaller inner ring, meanwhile, houses 72 apartments, a 160-room hotel across seven floors and a panoramic restaurant and viewing gallery. Perhaps most remarkable feature of of all, however, is a huge "bladeless turbine" that spans the center smaller ring.

Although this may look and sound like some of the more out-there architectural concepts that Gizmag has featured, it is actually based on existing (albeit prototypical) technology. The electrostatic wind energy convertor (EWICON) was developed at Delft Technical University and generates electricity by harnessing the movement of charged water droplets in the wind. Its lack of moving parts makes it noiseless and easier to maintain than traditional turbines.

Dhiradj Djairam, of the TU Delft team that developed the EWICON, tells Gizmag that the Dutch Windwheel Corporation has expressed "a serious interest" in the technology. Djairam says he has provided an explanation of the technology to the organization and provided a rough outline for a realistic research and development program. To date, only small-scale research projects have been carried out, with additional funding opportunities being explored.

The Dutch Windwheel concept is 174 m (571 ft) tall and has underwater foundations

The Dutch Windwheel concept has other sustainable aspects, too. Photovoltaic thermal hybrid panels would be used to contribute to the generation of electricity, and rainwater would be collected for use in the building. The Dutch Windwheel Corporation says the building itself is designed to be built with locally-sourced materials, and in such a way as it could ultimately be disassembled and re-used elsewhere.

Among the other features of the design are space for commercial functions in the structure's plinth, and foundations that are underwater, making it it look as though the structure is floating. 

We're told that the amount of power the Dutch Windwheel will require to run – and be able to generate – is not yet clear. Likewise, the final technologies and additional sustainability features that would be present in the building have yet to be finalized...

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UK Scientists: Aliens May Have Sent Space Seeds To Create Life On Earth

February 21, 2015 / / 0 Comments

Excerpt from huffingtonpost.comScientists in the U.K. have examined a tiny metal circular object, and are suggesting it might be a micro-organism deliberately sent by extraterrestrials to create life on Earth.Don't be fooled by the size of the objec...

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