Tag: strong (page 4 of 22)

Monster Black Hole’s Mighty Belch Could Transform Our Entire Galaxy

This artist's illustration depicts the furious cosmic winds streaming out from a monster supermassive black hole as detected by NASA's NuSTAR space telescope and the European Space Agency's XMM-Newton X-ray observatory.
This artist's illustration depicts the furious cosmic winds streaming out from a monster supermassive black hole as detected by NASA's NuSTAR space telescope and the European Space Agency's XMM-Newton X-ray observatory.


Except from space.com

A ravenous, giant black hole has belched up a bubble of cosmic wind so powerful that it could change the fate of an entire galaxy, according to new observations.
Researchers using two X-ray telescopes have identified a cosmic wind blowing outward from the supermassive black hole at the center of galaxy PDS 456. Astronomers have seen these winds before, but the authors of the new research say this is the first observation of a wind moving away from the center in every direction, creating a spherical shape.
The wind could have big implications for the future of the galaxy: It will cut down on the black hole's food supply, and slow star formation in the rest of the galaxy, the researchers said. And it's possible that strong cosmic winds are a common part of galaxy evolution — they could be responsible for turning galaxies from bright, active youngsters to quiet middle-agers. 

Big eater

The supermassive black hole at the center of PDS 456 is currently gobbling up a substantial amount of food: A smorgasbord of gas and dust surrounds the black hole and is falling into the gravitational sinkhole.
As matter falls, it radiates light. The black hole at the center of PDS 456 is devouring so much matter, that the resulting radiation outshines every star in the galaxy. These kinds of bright young galaxies are known as quasars: a galaxy with an incredibly bright center, powered by a supermassive black hole with a big appetite.
New observations of PDS 456 have revealed a bubble of gas moving outward, away from the black hole. Using NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) and ESA’s (European Space Agency) XMM-Newton, the authors of the new research imaged the galaxy on five separate occassions in 2013 and 2014. The researchers say they can show that the photons of light emitted by the in-falling matter are pushing on nearby gas, creating the wind.
Scientists have studied these cosmic winds before, but the authors of the new research say their work goes a step further.
"It tells us that the shape of the wind is not just a narrow beam pointed in our direction. It is really a wind that is flowing in every direction away from the black hole," said Emanuele Nardini, a postdoctoral researcher at Keele University in Staffordshire, England. "With a spherical wind, the amount of mass it carries out is much larger than just a narrow beam."
According to a statement from NASA, galaxy PDS 456 "sustains winds that carry more energy every second than is emitted by more than a trillion suns." Such powerful winds could change the entire landscape of PDS 456, the researchers say. First, the wind will blow through the disk of matter surrounding the black hole — this disk currently serves as the black hole's food supply. The cosmic wind created by the black hole's appetite could significantly reduce or destroy the disk. In other words, the black hole cannot have its cake and eat it, too. 

Bright young things

With no matter left to fall into the black hole, the radiation would cease as well. The brilliant center of the quasar will dim. By diminishing the black hole's food supply, they may turn quasars and other "active galaxies" like PDS 456 into quiescent galaxies like the Milky Way. Theorists have proposed that cosmic winds could explain why there are more young active galaxies than old active galaxies.
"We know that in almost every galaxy, a supermassive black hole resides in the center," said Nardini. "But, most of the galaxies we see today are quiescent, they are not active in any way. The fact that galaxies today are quiescent — we have to find an explanation for that in something that happened a long time ago."
In addition to quenching the radiation from an active black hole, these cosmic winds may slow down star formation in galaxies. The cosmic wind could blow through regions thick with gas and dust, where young stars form, and thin out the fertile stellar soil.
"If you have a black hole with this kind of wind, in millions of years [the winds] will be able to quench star formation and create a galaxy like our own," Nardini said. Stars will still form in the Milky Way, but not at the high rate of many young galaxies.
It's possible that these cosmic winds are a central reason why most galaxies go from being brightly burning active youngsters to quiet middle-agers.

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Poll Reveals Public Skepticism of Government and Private Human Spaceflight

SpaceShipTwo powered test flight
A poll found 58 percent of people said private companies like Virgin Galactic should be allowed to send people to space, which it plans to do via its suborbital SpaceShipTwo vehicle (shown during a powered test flight). Credit: Virgin Galactic


Excerpt from spacenews.com

WASHINGTON — The American public is skeptical that private ventures will be able to launch “ordinary people” into space in the coming decades, and is split about spending money on government-led human space exploration, a new poll indicates. 

 The Monmouth University Poll results, released Feb. 16, showed that a majority of Americans believe private companies should be permitted to launch people into space, but also that they did not believe it likely those companies would be able to do so in next 20 to 30 years.  In the poll, 58 percent of people said private companies should be allowed to launch people in space, versus 37 percent who said that human spaceflight should be left to governments alone. 

However, 55 percent thought it was not likely that “ordinary people will be able to travel regularly” into space in the next 20 to 30 years, while 44 percent said such travel would be somewhat or very likely.  Most people also said they were unwilling to fly in space themselves: 69 percent said they would decline a free trip into space, while 28 percent said they would accept it. The poll did not specify what kind of trip — suborbital or orbital — was offered.  The poll revealed a sharp difference in gender, with men more willing than women to believe private ventures should be allowed to fly people in space. Men supported private over government-only human spaceflight by a margin of 71 to 26 percent. 

Women, though were, more evenly split, with 44 percent backing private human spaceflight and 49 percent supporting government-only efforts. MoonFifty percent of those polled said the U.S. government should not spend “billions of dollars to send astronauts to places like the moon, Mars, and asteroids.” 

The public is also divided about spending money on government human space exploration. Asked if the U.S. government should spend “billions of dollars to send astronauts to places like the moon, Mars, and asteroids,” 50 percent said no, while 42 percent said yes.  As with private spaceflight, there was a strong gender split, with 50 percent of men, but only 36 percent of women, supporting spending on human space exploration. There was, by contrast, little difference by party affiliation.  

The poll showed greater support for government spending on space in general. Asked if increased spending on the space program in general would be “a good investment for the country,” 51 percent agreed and 43 percent disagreed.  The poll is based on a telephone survey of 1,008 people in December, and has an overall margin of error of 3.1 percent.
WASHINGTON — The American public is skeptical that private ventures will be able to launch “ordinary people” into space in the coming decades, and is split about spending money on government-led human space exploration, a new poll indicates.
The Monmouth University Poll results, released Feb. 16, showed that a majority of Americans believe private companies should be permitted to launch people into space, but also that they did not believe it likely those companies would be able to do so in next 20 to 30 years.
In the poll, 58 percent of people said private companies should be allowed to launch people in space, versus 37 percent who said that human spaceflight should be left to governments alone. However, 55 percent thought it was not likely that “ordinary people will be able to travel regularly” into space in the next 20 to 30 years, while 44 percent said such travel would be somewhat or very likely.
Most people also said they were unwilling to fly in space themselves: 69 percent said they would decline a free trip into space, while 28 percent said they would accept it. The poll did not specify what kind of trip — suborbital or orbital — was offered.
The poll revealed a sharp difference in gender, with men more willing than women to believe private ventures should be allowed to fly people in space. Men supported private over government-only human spaceflight by a margin of 71 to 26 percent. Women, though were, more evenly split, with 44 percent backing private human spaceflight and 49 percent supporting government-only efforts.
Moon
Fifty percent of those polled said the U.S. government should not spend “billions of dollars to send astronauts to places like the moon, Mars, and asteroids.” Credit: NASA
The public is also divided about spending money on government human space exploration. Asked if the U.S. government should spend “billions of dollars to send astronauts to places like the moon, Mars, and asteroids,” 50 percent said no, while 42 percent said yes.
As with private spaceflight, there was a strong gender split, with 50 percent of men, but only 36 percent of women, supporting spending on human space exploration. There was, by contrast, little difference by party affiliation.
The poll showed greater support for government spending on space in general. Asked if increased spending on the space program in general would be “a good investment for the country,” 51 percent agreed and 43 percent disagreed.
The poll is based on a telephone survey of 1,008 people in December, and has an overall margin of error of 3.1 percent.
- See more at: http://spacenews.com/poll-reveals-public-skepticism-of-government-and-private-human-spaceflight/#sthash.6PxcrjTQ.dpuf

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Why science is so hard to believe?

 
In the recent movie “Interstellar,” set in a futuristic, downtrodden America where NASA has been forced into hiding, school textbooks say the Apollo moon landings were faked.


Excerpt from 


There’s a scene in Stanley Kubrick’s comic masterpiece “Dr. Strangelove” in which Jack D. Ripper, an American general who’s gone rogue and ordered a nuclear attack on the Soviet Union, unspools his paranoid worldview — and the explanation for why he drinks “only distilled water, or rainwater, and only pure grain alcohol” — to Lionel Mandrake, a dizzy-with-anxiety group captain in the Royal Air Force.
Ripper: “Have you ever heard of a thing called fluoridation? Fluoridation of water?”
Mandrake: “Ah, yes, I have heard of that, Jack. Yes, yes.”Ripper: “Well, do you know what it is?”
Mandrake: “No. No, I don’t know what it is, no.”
Ripper: “Do you realize that fluoridation is the most monstrously conceived and dangerous communist plot we have ever had to face?” 

The movie came out in 1964, by which time the health benefits of fluoridation had been thoroughly established and anti-fluoridation conspiracy theories could be the stuff of comedy. Yet half a century later, fluoridation continues to incite fear and paranoia. In 2013, citizens in Portland, Ore., one of only a few major American cities that don’t fluoridate, blocked a plan by local officials to do so. Opponents didn’t like the idea of the government adding “chemicals” to their water. They claimed that fluoride could be harmful to human health.

Actually fluoride is a natural mineral that, in the weak concentrations used in public drinking-water systems, hardens tooth enamel and prevents tooth decay — a cheap and safe way to improve dental health for everyone, rich or poor, conscientious brushers or not. That’s the scientific and medical consensus.
To which some people in Portland, echoing anti-fluoridation activists around the world, reply: We don’t believe you.
We live in an age when all manner of scientific knowledge — from the safety of fluoride and vaccines to the reality of climate change — faces organized and often furious opposition. Empowered by their own sources of information and their own interpretations of research, doubters have declared war on the consensus of experts. There are so many of these controversies these days, you’d think a diabolical agency had put something in the water to make people argumentative.
Science doubt has become a pop-culture meme. In the recent movie “Interstellar,” set in a futuristic, downtrodden America where NASA has been forced into hiding, school textbooks say the Apollo moon landings were faked.


The debate about mandated vaccinations has the political world talking. A spike in measles cases nationwide has President Obama, lawmakers and even potential 2016 candidates weighing in on the vaccine controversy. (Pamela Kirkland/The Washington Post)
In a sense this is not surprising. Our lives are permeated by science and technology as never before. For many of us this new world is wondrous, comfortable and rich in rewards — but also more complicated and sometimes unnerving. We now face risks we can’t easily analyze.
We’re asked to accept, for example, that it’s safe to eat food containing genetically modified organisms (GMOs) because, the experts point out, there’s no evidence that it isn’t and no reason to believe that altering genes precisely in a lab is more dangerous than altering them wholesale through traditional breeding. But to some people, the very idea of transferring genes between species conjures up mad scientists running amok — and so, two centuries after Mary Shelley wrote “Frankenstein,” they talk about Frankenfood.
The world crackles with real and imaginary hazards, and distinguishing the former from the latter isn’t easy. Should we be afraid that the Ebola virus, which is spread only by direct contact with bodily fluids, will mutate into an airborne super-plague? The scientific consensus says that’s extremely unlikely: No virus has ever been observed to completely change its mode of transmission in humans, and there’s zero evidence that the latest strain of Ebola is any different. But Google “airborne Ebola” and you’ll enter a dystopia where this virus has almost supernatural powers, including the power to kill us all.
In this bewildering world we have to decide what to believe and how to act on that. In principle, that’s what science is for. “Science is not a body of facts,” says geophysicist Marcia McNutt, who once headed the U.S. Geological Survey and is now editor of Science, the prestigious journal. “Science is a method for deciding whether what we choose to believe has a basis in the laws of nature or not.”
The scientific method leads us to truths that are less than self-evident, often mind-blowing and sometimes hard to swallow. In the early 17th century, when Galileo claimed that the Earth spins on its axis and orbits the sun, he wasn’t just rejecting church doctrine. He was asking people to believe something that defied common sense — because it sure looks like the sun’s going around the Earth, and you can’t feel the Earth spinning. Galileo was put on trial and forced to recant. Two centuries later, Charles Darwin escaped that fate. But his idea that all life on Earth evolved from a primordial ancestor and that we humans are distant cousins of apes, whales and even deep-sea mollusks is still a big ask for a lot of people.
Even when we intellectually accept these precepts of science, we subconsciously cling to our intuitions — what researchers call our naive beliefs. A study by Andrew Shtulman of Occidental College showed that even students with an advanced science education had a hitch in their mental gait when asked to affirm or deny that humans are descended from sea animals and that the Earth goes around the sun. Both truths are counterintuitive. The students, even those who correctly marked “true,” were slower to answer those questions than questions about whether humans are descended from tree-dwelling creatures (also true but easier to grasp) and whether the moon goes around the Earth (also true but intuitive).
Shtulman’s research indicates that as we become scientifically literate, we repress our naive beliefs but never eliminate them entirely. They nest in our brains, chirping at us as we try to make sense of the world.
Most of us do that by relying on personal experience and anecdotes, on stories rather than statistics. We might get a prostate-specific antigen test, even though it’s no longer generally recommended, because it caught a close friend’s cancer — and we pay less attention to statistical evidence, painstakingly compiled through multiple studies, showing that the test rarely saves lives but triggers many unnecessary surgeries. Or we hear about a cluster of cancer cases in a town with a hazardous-waste dump, and we assume that pollution caused the cancers. Of course, just because two things happened together doesn’t mean one caused the other, and just because events are clustered doesn’t mean they’re not random. Yet we have trouble digesting randomness; our brains crave pattern and meaning.
Even for scientists, the scientific method is a hard discipline. They, too, are vulnerable to confirmation bias — the tendency to look for and see only evidence that confirms what they already believe. But unlike the rest of us, they submit their ideas to formal peer review before publishing them. Once the results are published, if they’re important enough, other scientists will try to reproduce them — and, being congenitally skeptical and competitive, will be very happy to announce that they don’t hold up. Scientific results are always provisional, susceptible to being overturned by some future experiment or observation. Scientists rarely proclaim an absolute truth or an absolute certainty. Uncertainty is inevitable at the frontiers of knowledge.
That provisional quality of science is another thing a lot of people have trouble with. To some climate-change skeptics, for example, the fact that a few scientists in the 1970s were worried (quite reasonably, it seemed at the time) about the possibility of a coming ice age is enough to discredit what is now the consensus of the world’s scientists: The planet’s surface temperature has risen by about 1.5 degrees Fahrenheit in the past 130 years, and human actions, including the burning of fossil fuels, are extremely likely to have been the dominant cause since the mid-20th century.
It’s clear that organizations funded in part by the fossil-fuel industry have deliberately tried to undermine the public’s understanding of the scientific consensus by promoting a few skeptics. The news media gives abundant attention to such mavericks, naysayers, professional controversialists and table thumpers. The media would also have you believe that science is full of shocking discoveries made by lone geniuses. Not so. The (boring) truth is that science usually advances incrementally, through the steady accretion of data and insights gathered by many people over many years. So it has with the consensus on climate change. That’s not about to go poof with the next thermometer reading.
But industry PR, however misleading, isn’t enough to explain why so many people reject the scientific consensus on global warming.
The “science communication problem,” as it’s blandly called by the scientists who study it, has yielded abundant new research into how people decide what to believe — and why they so often don’t accept the expert consensus. It’s not that they can’t grasp it, according to Dan Kahan of Yale University. In one study he asked 1,540 Americans, a representative sample, to rate the threat of climate change on a scale of zero to 10. Then he correlated that with the subjects’ science literacy. He found that higher literacy was associated with stronger views — at both ends of the spectrum. Science literacy promoted polarization on climate, not consensus. According to Kahan, that’s because people tend to use scientific knowledge to reinforce their worldviews.
Americans fall into two basic camps, Kahan says. Those with a more “egalitarian” and “communitarian” mind-set are generally suspicious of industry and apt to think it’s up to something dangerous that calls for government regulation; they’re likely to see the risks of climate change. In contrast, people with a “hierarchical” and “individualistic” mind-set respect leaders of industry and don’t like government interfering in their affairs; they’re apt to reject warnings about climate change, because they know what accepting them could lead to — some kind of tax or regulation to limit emissions.
In the United States, climate change has become a litmus test that identifies you as belonging to one or the other of these two antagonistic tribes. When we argue about it, Kahan says, we’re actually arguing about who we are, what our crowd is. We’re thinking: People like us believe this. People like that do not believe this.
Science appeals to our rational brain, but our beliefs are motivated largely by emotion, and the biggest motivation is remaining tight with our peers. “We’re all in high school. We’ve never left high school,” says Marcia McNutt. “People still have a need to fit in, and that need to fit in is so strong that local values and local opinions are always trumping science. And they will continue to trump science, especially when there is no clear downside to ignoring science.”
Meanwhile the Internet makes it easier than ever for science doubters to find their own information and experts. Gone are the days when a small number of powerful institutions — elite universities, encyclopedias and major news organizations — served as gatekeepers of scientific information. The Internet has democratized it, which is a good thing. But along with cable TV, the Web has also made it possible to live in a “filter bubble” that lets in only the information with which you already agree.
How to penetrate the bubble? How to convert science skeptics? Throwing more facts at them doesn’t help. Liz Neeley, who helps train scientists to be better communicators at an organization called Compass, says people need to hear from believers they can trust, who share their fundamental values. She has personal experience with this. Her father is a climate-change skeptic and gets most of his information on the issue from conservative media. In exasperation she finally confronted him: “Do you believe them or me?” She told him she believes the scientists who research climate change and knows many of them personally. “If you think I’m wrong,” she said, “then you’re telling me that you don’t trust me.” Her father’s stance on the issue softened. But it wasn’t the facts that did it.
If you’re a rationalist, there’s something a little dispiriting about all this. In Kahan’s descriptions of how we decide what to believe, what we decide sometimes sounds almost incidental. Those of us in the science-communication business are as tribal as anyone else, he told me. We believe in scientific ideas not because we have truly evaluated all the evidence but because we feel an affinity for the scientific community. When I mentioned to Kahan that I fully accept evolution, he said: “Believing in evolution is just a description about you. It’s not an account of how you reason.”
Maybe — except that evolution is real. Biology is incomprehensible without it. There aren’t really two sides to all these issues. Climate change is happening. Vaccines save lives. Being right does matter — and the science tribe has a long track record of getting things right in the end. Modern society is built on things it got right.
Doubting science also has consequences, as seen in recent weeks with the measles outbreak that began in California. The people who believe that vaccines cause autism — often well educated and affluent, by the way — are undermining “herd immunity” to such diseases as whooping cough and measles. The anti-vaccine movement has been going strong since a prestigious British medical journal, the Lancet, published a study in 1998 linking a common vaccine to autism. The journal later retracted the study, which was thoroughly discredited. But the notion of a vaccine-autism connection has been endorsed by celebrities and reinforced through the usual Internet filters. (Anti-vaccine activist and actress Jenny McCarthy famously said on “The Oprah Winfrey Show,” “The University of Google is where I got my degree from.”)
In the climate debate, the consequences of doubt are likely to be global and enduring. Climate-change skeptics in the United States have achieved their fundamental goal of halting legislative action to combat global warming. They haven’t had to win the debate on the merits; they’ve merely had to fog the room enough to keep laws governing greenhouse gas emissions from being enacted.
Some environmental activists want scientists to emerge from their ivory towers and get more involved in the policy battles. Any scientist going that route needs to do so carefully, says Liz Neeley. “That line between science communication and advocacy is very hard to step back from,” she says. In the debate over climate change, the central allegation of the skeptics is that the science saying it’s real and a serious threat is politically tinged, driven by environmental activism and not hard data. That’s not true, and it slanders honest scientists. But the claim becomes more likely to be seen as plausible if scientists go beyond their professional expertise and begin advocating specific policies.
It’s their very detachment, what you might call the cold-bloodedness of science, that makes science the killer app. It’s the way science tells us the truth rather than what we’d like the truth to be. Scientists can be as dogmatic as anyone else — but their dogma is always wilting in the hot glare of new research. In science it’s not a sin to change your mind when the evidence demands it. For some people, the tribe is more important than the truth; for the best scientists, the truth is more important than the tribe.

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Mysterious plumes in Mars’ atmosphere baffle astronomers




Excerpt from thespacereporter.com

Astronomers are baffled by images of plumes rising from Mars’ atmosphere in images taken by amateur astronomers in March and April 2012.

The plumes were present for about 10 days though their shapes and sizes changed rapidly during that time, from finger-like tendrils to spherical blobs.

Researchers have proposed several possible explanations for the plumes, which are discussed in an article just published in the journal Nature.

Each of the theories being considered poses problems. One theory, for instaqnce, proposes the plumes are caused by the same magnetic influence that causes the aurora borealis, or Northern Lights, on Earth. The movement of electrically charged particles from the Sun, driven by the solar wind towards Earth’s poles, results in these particles colliding with molecules of gas. These collisions produce the strange lights known as aurorae.

In the study, the researchers admit, “Mars aurorae have been observed near where the plume occurs, a region with a large anomaly in the crustal magnetic field that can drive the precipitation of solar wind particles into the atmosphere.”
The problem with this theory is this would only happen if the Sun released an exceptional amount of energetic particles during the time the plumes were seen. Yet the level of solar output in 2012 was nowhere near sufficient to release such a powerful stream of particles, the authors of the paper acknowledge.

They move on to consider another option, namely that the plumes might be clouds high in the Martian atmosphere.

A highly reflective cloud of either water ice, carbon dioxide ice, or dust particles could explain the plumes. But according to computer models, the presence of these clouds “would require exceptional deviations from standard atmospheric circulation models to explain cloud formations at such high altitudes,” explained the paper’s lead author, Agustin Sanchez-Lavega of the Universidad del Pais Vasco in Spain.

The plumes were seen approximately 120 miles (200 km) from Mars’ surface, which is problematic because the highest Martian clouds are seen is 60 miles (100 km) above the planet’s surface. The only way water can condense so far up is if the temperature in that part of Mars’ atmosphere drops 370 degrees Fahrenheit, or 50 degrees Kelvin, below its norm.

Condensation of carbon dioxide would require twice this temperature drop.

A third theory posits the flumes are caused by atmospheric dust. A wind powerful enough to transport dust 111 miles (180 km) above Mars’ surface could occur only around noon, when the Sun’s heat would be strong enough to create such wind currents.

However, the plumes were seen not at noon but in the mornings along the terminator that separates the planet’s day and night sides.
Recently, data from the Hubble Space Telescope was found showing the plumes back in 1997.

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


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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Every Black Hole Contains a New Universe


At the center of spiral galaxy M81 is a supermassive black hole about 70 million times more massive than our sun.



Excerpt from insidescience.org
A physicist presents a solution to present-day cosmic mysteries.



By: 
Nikodem Poplawski, Inside Science Minds Guest Columnist



(ISM) -- Our universe may exist inside a black hole. This may sound strange, but it could actually be the best explanation of how the universe began, and what we observe today. It's a theory that has been explored over the past few decades by a small group of physicists including myself. 
Successful as it is, there are notable unsolved questions with the standard big bang theory, which suggests that the universe began as a seemingly impossible "singularity," an infinitely small point containing an infinitely high concentration of matter, expanding in size to what we observe today. The theory of inflation, a super-fast expansion of space proposed in recent decades, fills in many important details, such as why slight lumps in the concentration of matter in the early universe coalesced into large celestial bodies such as galaxies and clusters of galaxies.
But these theories leave major questions unresolved. For example: What started the big bang? What caused inflation to end? What is the source of the mysterious dark energy that is apparently causing the universe to speed up its expansion?
The idea that our universe is entirely contained within a black hole provides answers to these problems and many more. It eliminates the notion of physically impossible singularities in our universe. And it draws upon two central theories in physics.
Nikodem Poplawski displays a "tornado in a tube." The top bottle symbolizes a black hole, the connected necks represent a wormhole and the lower bottle symbolizes the growing universe on the just-formed other side of the wormhole. Credit: Indiana University
In this picture, spins in particles interact with spacetime and endow it with a property called "torsion." To understand torsion, imagine spacetime not as a two-dimensional canvas, but as a flexible, one-dimensional rod. Bending the rod corresponds to curving spacetime, and twisting the rod corresponds to spacetime torsion. If a rod is thin, you can bend it, but it's hard to see if it's twisted or not.

The first is general relativity, the modern theory of gravity. It describes the universe at the largest scales. Any event in the universe occurs as a point in space and time, or spacetime. A massive object such as the Sun distorts or "curves" spacetime, like a bowling ball sitting on a canvas. The Sun's gravitational dent alters the motion of Earth and the other planets orbiting it. The sun's pull of the planets appears to us as the force of gravity.

The second is quantum mechanics, which describes the universe at the smallest scales, such as the level of the atom. However, quantum mechanics and general relativity are currently separate theories; physicists have been striving to combine the two successfully into a single theory of "quantum gravity" to adequately describe important phenomena, including the behavior of subatomic particles in black holes.
A 1960s adaptation of general relativity, called the Einstein-Cartan-Sciama-Kibble theory of gravity, takes into account effects from quantum mechanics. It not only provides a step towards quantum gravity but also leads to an alternative picture of the universe. This variation of general relativity incorporates an important quantum property known as spin. Particles such as atoms and electrons possess spin, or the internal angular momentum that is analogous to a skater spinning on ice.

Spacetime torsion would only be significant, let alone noticeable, in the early universe or in black holes. In these extreme environments, spacetime torsion would manifest itself as a repulsive force that counters the attractive gravitational force coming from spacetime curvature. As in the standard version of general relativity, very massive stars end up collapsing into black holes: regions of space from which nothing, not even light, can escape.
Here is how torsion would play out in the beginning moments of our universe. Initially, the gravitational attraction from curved space would overcome torsion's repulsive forces, serving to collapse matter into smaller regions of space. But eventually torsion would become very strong and prevent matter from compressing into a point of infinite density; matter would reach a state of extremely large but finite density. As energy can be converted into mass, the immensely high gravitational energy in this extremely dense state would cause an intense production of particles, greatly increasing the mass inside the black hole.
The increasing numbers of particles with spin would result in higher levels of spacetime torsion. The repulsive torsion would stop the collapse and would create a "big bounce" like a compressed beach ball that snaps outward. The rapid recoil after such a big bounce could be what has led to our expanding universe. The result of this recoil matches observations of the universe's shape, geometry, and distribution of mass.
In turn, the torsion mechanism suggests an astonishing scenario: every black hole would produce a new, baby universe inside. If that is true, then the first matter in our universe came from somewhere else. So our own universe could be the interior of a black hole existing in another universe. Just as we cannot see what is going on inside black holes in the cosmos, any observers in the parent universe could not see what is going on in ours.
The motion of matter through the black hole's boundary, called an "event horizon," would only happen in one direction, providing a direction of time that we perceive as moving forward. The arrow of time in our universe would therefore be inherited, through torsion, from the parent universe.
Torsion could also explain the observed imbalance between matter and antimatter in the universe. Because of torsion, matter would decay into familiar electrons and quarks, and antimatter would decay into "dark matter," a mysterious invisible form of matter that appears to account for a majority of matter in the universe.
Finally, torsion could be the source of "dark energy," a mysterious form of energy that permeates all of space and increases the rate of expansion of the universe. Geometry with torsion naturally produces a "cosmological constant," a sort of added-on outward force which is the simplest way to explain dark energy. Thus, the observed accelerating expansion of the universe may end up being the strongest evidence for torsion.
Torsion therefore provides a theoretical foundation for a scenario in which the interior of every black hole becomes a new universe. It also appears as a remedy to several major problems of current theory of gravity and cosmology. Physicists still need to combine the Einstein-Cartan-Sciama-Kibble theory fully with quantum mechanics into a quantum theory of gravity. While resolving some major questions, it raises new ones of its own. For example, what do we know about the parent universe and the black hole inside which our own universe resides? How many layers of parent universes would we have? How can we test that our universe lives in a black hole?
The last question can potentially be investigated: since all stars and thus black holes rotate, our universe would have inherited the parent black hole’s axis of rotation as a "preferred direction." There is some recently reported evidence from surveys of over 15,000 galaxies that in one hemisphere of the universe more spiral galaxies are "left-handed", or rotating clockwise, while in the other hemisphere more are "right-handed", or rotating counterclockwise. In any case, I believe that including torsion in geometry of spacetime is a right step towards a successful theory of cosmology.

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Moonquakes and blazing heat: What would life really be like on the Moon?


Lunar Base Made with 3D Printing


Excerpt from space.com

The idea of building a lunar outpost has long captured people's imaginations. But what would it really be like to live on the moon?
Space exploration has long focused on the moon, with Earth's satellite the setting for a number of significant missions. A 1959 Soviet spacecraft photographed the moon's far side for the first time, and in 1969, NASA landed people on the lunar surface for the first time. Numerous missions followed, including NASA's Lunar Reconnaissance Orbiter that beamed home the highest-resolution topographical lunar map to date, covering 98.2 percent of the moon's surface. 

Altogether, data beamed back from numerous missions suggest that no place on the moon would be a pleasant place to live, at least compared with Earth. Lunar days stretch for about 14 Earth days with average temperatures of 253 degrees Fahrenheit (123 degrees Celsius), while lunar nights also last 14 Earth days (due to the moon's rotation) and maintain a frigid cold of minus 387 degrees Fahrenheit (minus 233 degrees Celsius). 

"About the only place we could build a base that wouldn't have to deal with these extremes is, oddly enough, near the lunar poles," said Rick Elphic, project scientist for NASA's LADEE probe, which studied the moon's atmosphere and dust environment before performing a planned crash into the natural satellitein April 2014. These areas likely store vast amounts of water-ice and enjoy low levels of light from the sun for several months at a time.

"Instead of the blazing heat of lunar noon, it is a kind of perpetual balmy sunset, with temperatures around 0 degrees Celsius [32 degrees Fahrenheit] due to the low angle of the sun," Elphic added.

Vacations away from pole outposts would offer up sights unlike anything on Earth. Decorating the moon's vast lava plains are large impact-borne "mountains," the tallest of which is 3.4 miles (5.5 kilometers) high, about the size of Mount Saint Elias on the border of Alaska and Canada. "Skylight" holes puncture some of the plains where lava likely drained into sub-surface caverns — the perfect adventure for lunar spelunkers.

The moon also sports huge craters, such as the 25-mile-wide (40 km) Aristarchus crater. A view from the rim of Aristarchus would "dwarf the Grand Canyon and make Meteor Crater in Arizona look like a hole in a putting green," Elphic told Space.com via email.


Lunar athletes would not need to check the forecast, however. Because of its very tenuous atmosphere, the moon has no weather. "Every day is sunny with no chance of rain!" Elphic added. You would, however, have to look out for so-called space weather, which includes meteor particles that can be as large as golf balls and highly energetic particles from solar flares.

Another potential danger would be moonquakes. Seismometers left on the lunar surface during Apollo show that the moon is still seismically active, and even has rare, hour-long quakes measuring up to 5.5 on the Richter scale. These quakes would be strong enough to cause structural damage to buildings.

"So don't leave Earth for your home on the moon thinking you've left seismic activity behind," Elphic said. "Make sure your lunar house is up to code."

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Hubble Telescope spots a gigantic ‘smile’ in deep space

The Hubble Telescope captured an image of an enormous galaxy cluster which appears to be smiling at its galactic neighbors.  SpaceTelescope.org elaborates:"In the case of this 'happy face', the two eyes are very bright galaxies and the misl...

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New internet neutrality: FCC chairman proposes strong new rules

Excerpt from mercurynews.comThe federal government's top communications regulator on Wednesday called for strong new rules to bar Internet and wireless providers from blocking, slowing or discriminating against consumers' access to particular websi...

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6 Supermaterials That Could Change Our World


Graphene

Excerpt from gizmodo.com

Graphene isn't the only game-changing material to come out of a lab. From aerogels nearly as light as air to metamaterials that manipulate light, here are six supermaterials that have the potential to transform the world of the future.

Self-healing Materials — Bioinspired Plastics

6 Supermaterials That Could Change Our World 
Self-healing plastic. Image credit: UIUC


The human body is very good at fixing itself. The built environment is not. Scott White at the University of Illinois at Urbana Champlain has been engineering bioinspired plastics that can self-heal. Last year, White's lab created a new polymer that oozes to repair a visible hole. The polymer is embedded with a vascular system of liquids that when broken and combined, clot just like blood. While other materials have been able to heal microscopic cracks, this new one repaired a hole 4 millimeter wide with cracks radiating all around it. Not big deal for a human skin, but a pretty big deal for plastic.

Engineers have also been envisioning concrete, asphalt, and metal that can heal themselves. (Imagine a city with no more potholes!) The rub, of course, lies in making them cheap enough to actually use, which is why the first applications for self-healing materials are most likely to be in space or in remote areas on Earth. 

Thermoelectric Materials — Heat Scavengers

6 Supermaterials That Could Change Our World 
Power blocks with thermoelectric material sued inside Alphabet Energy 's generator. Image credit: Alphabet Energy


If you've ever had a laptop burn up in your lap or touched the hot hood of car, then you've felt evidence of waste. Waste heat is the inevitable effect of running any that device that uses power. One estimate puts the amount of waste heat as two-thirds of all energy used. But what if there was a way to capture all that wasted energy? The answer to that "what if" is thermoelectric materials, which makes electricity from a temperature gradient.

Last year, California-based Alphabet Energy introduced a thermoelectric generator that plugs right into the exhaust pipe of ordinary generator, turning waste heat back into useful electricity. Alphabet Energy's generator uses a relatively cheap and naturally occurring thermoelectric material called tetrahedrite. Alphabet Energy says tetrahedrite can reach 5 to 10 percent efficiency.
Back in the lab, scientists have also been tinkering with another promising and possibly even more efficient thermoelectric material called skutterudite, which is a type of mineral that contains cobalt. Thermoelectric materials have already had niche applications—like on spacecraft—but skutterudite could get cheap and efficient enough to be wrapped around the exhaust pipes of cars or fridges or any other power-hogging machine you can think of. [Nature, MIT Technology Review, New Scientist]

Perovskites — Cheap Solar Cells

6 Supermaterials That Could Change Our World 
Solar cells made of perovskites. Image credit: University of Oxford


The biggest hurdle in moving toward renewable energy is, as these things always are, money. Solar power is getting ever cheaper, but making a plant's worth of solar cells from crystalline silicon is still an expensive, energy-intensive process. There's an alternative material that has the solar world buzzing though, and that's perovskites. 

Perovskites were first discovered over a century ago, but scientists are only just realizing its potential. In 2009, solar cells made from perovskites had a solar energy conversion efficiency of a measly 3.8 percent. In 2014, the number had leapt to 19.3 percent. That may not seem like much compared to traditional crystalline silicon cells with efficiencies hovering around 20 percent, but there's two other crucial points to consider: 1) perovskites have made such leaps and bounds in efficiency in just a few years that scientist think it can get even better and 2) perovskites are much, much cheaper. 

Perovskites are a class of materials defined by a particular crystalline structure. They can contain any number of elements, usually lead and tin for perovskites used in solar cells. These raw materials are cheap compared to crystalline silicon, and they can be sprayed onto glass rather than meticulously assembled in clean rooms. Oxford Photovoltaics is one of the leading companies trying to commercialize perovskites, which as wonderful as they have been in the lab, still do need to hold up in the real world. [WSJ, IEEE Spectrum, Chemical & Engineering News, Nature Materials]

Aerogels — Superlight and Strong

6 Supermaterials That Could Change Our World 
Image credit: NASA

Aerogels look like they should not be real. Although ghostly and ethereal, they can easily withstand the heat of a blowtorch and the weight of a car. The material is almost what exactly the name implies: gels where where the liquid has been replaced entirely by air. But you can see why it's also been called "frozen smoke" or "blue smoke." The actual matrix of an aerogel can be made of any number of substances, including silica, metal oxides, and, yes, also graphene. But the fact that aerogel is actually mostly made of air means that it's an excellent insulator (see: blowtorch). Its structure also makes it incredibly strong (see: car).

Aerogels do have one fatal flaw though: brittleness, especially when made from silica. But NASA scientists have been experimenting with flexible aerogels made of polymers to use insulators for spacecraft burning through the atmosphere. Mixing other compounds into even silica-based aerogels could make them more flexible. Add that to aerogel's lightness, strength, and insulating qualities, and that's one incredible material. [New Scientist, Gizmodo]

Metamaterials — Light Manipulators

If you've heard of metamaterials, you likely heard about it in a sentence that also mentioned "Harry Potter" and "invisibility cloak." And indeed, metamaterials, whose nanostructures are design to scatter light in specific ways, could possibly one day be used to render objects invisible—though it still probably wouldn't be as magical as Harry Potter's invisibility cloak. 

What's more interesting about metamaterials is that they don't just redirect visible light. Depending on how and what a particular metamaterial is made of, it can also scatter microwaves, radiowaves, or the little-known T-rays, which are between microwaves and infrared light on the electromagnetic spectrum. Any piece of electromagnetic spectrum could be manipulated by metamaterials. 

That could be, for example, new T-ray scanners in medicine or security or a compact radio antennae made of metamaterials whose properties change on the fly. Metamaterials are at the promising but frustrating cusp where the theoretical possibilities are endless, but commercialization is still a long, hard road. [Nature, Discover Magazine]

Stanene — 100 percent efficient conductor

6 Supermaterials That Could Change Our World 
The molecular structure of stanene. Image credit: SLAC


Like the much better known graphene, stanene is also made of a single layer of atoms. But instead of carbon, stanene is made of tin, and this makes all the difference in allowing stanene to possibly do what even wondermaterial extraordinaire graphene cannot: conduct electricity with 100 percent efficiency.

Stanene was first theorized in 2013 by Stanford professor Shoucheng Zhang, whose lab specializes in, along other things, predicting the electronic properties of materials like stanene. According to their models, stanene is a topological insulator, which means its edges are a conductor and its inside is an insulator. (Think of a chocolate-covered ice cream bar. Chocolate conductor, ice cream insulator.) 

This means stanene could conduct electricity with zero resistance even, crucially, at room temperature. Stanene's properties have yet to been tested experimentally—making a single-atom sheet tin is no easy task—but several of Zhang's predictions about other topological insulators have proven correct.

If the predictions about stanene bear out, it could revolutionize the microchips inside all your devices. Namely, the chips could get a lot more powerful. Silicon chips are limited by the heat created by electrons zipping around—work 'em too fast and they'll simply get too hot. Stanene, which conducts electricity 100 percent efficiency, would have no such problem. [SLAC, Physical Review Letters, Scientific American]

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Neptune-Like Planets Could Transfom Into Habitable Worlds

Strong irradiation from the host star can cause planets known as mini-Neptunes in the habitable zone to shed their gaseous envelopes and become potentially habitable worlds.Credit: Rodrigo Luger / NASA imagesExcerpt from sciencedaily.com Two ph...

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Taiwan Conference Report / Solar System Situation Update

Taiwan conference was a huge success. Because Taiwan is one of the main centers of the positive Dragon forces, it could grow a very strong Lightworker and Lightwarrior community. The conference took place very close to the location where Taiwanese Drag...

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The Weirdest, Coolest Stuff We’ve Learned About Rosetta’s Comet So Far


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.

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