Ceres Excerpt from cnet.com It's a real-life mystery cliffhanger. We've come up with a list of possible reasons a large crater on the biggest object in the asteroid belt looks lit up like a Christmas tree. We could be approachin...
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| Artist impression of Mars ocean |
Excerpt from news.discovery.com
Mars was once a small, wet and blue world, but over the past 4 billion years, Mars dried up and became the red dust bowl we know today.
But how much water did Mars possess? According to research published in the journal Science, the Martian northern hemisphere was likely covered in an ocean, covering a region of the approximate area as Earth’s Atlantic Ocean, plunging, in some places, to 1.6 kilometers (1 mile) deep.
“Our study provides a solid estimate of how much water Mars once had, by determining how much water was lost to space,” said Geronimo Villanueva, of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the new paper, in an ESO news release. “With this work, we can better understand the history of water on Mars.”
Over a 6-year period, Villanueva and his team used the ESO’s Very Large Telescope (in Chile) and instruments at the W. M. Keck Observatory and the NASA Infrared Telescope Facility (both on Mauna Kea in Hawaii) to study the distribution of water molecules in the Martian atmosphere. By building a comprehensive map of water distribution and seasonal changes, they were able to arrive at this startling conclusion.
It is becoming clear that, over the aeons, Mars lost the majority of its atmosphere to space. That also goes for its water. Though large quantities of water were likely frozen below the surface as the atmosphere thinned and cooled, the water contained in an ocean of this size must have gone elsewhere — it must have also been lost to space.
The water in Earth’s oceans contains molecules of H2O, the familiar oxygen atom bound with 2 hydrogen atoms, and, in smaller quantities, the not-so-familiar HDO molecule. HDO is a type of water molecule that contains 1 hydrogen atom, 1 oxygen atom and 1 deuterium atom. The deuterium atom is an isotope of hydrogen; whereas hydrogen consists of 1 proton and an electron, deuterium consists of 1 proton, 1 neutron and 1 electron. Therefore, due to the extra neutron the deuterium contains, HDO molecules are slightly heavier than the regular H2O molecules.
Also known as “semi-heavy water,” HDO is less susceptible to being evaporated away and being lost to space, so logic dictates that if water is boiled (or sublimated) away on Mars, the H2O molecules will be preferentially lost to space whereas a higher proportion of HDO will be left behind.
By using powerful ground-based observatories, the researchers were able to determine the distribution of HDO molecules and the H2O molecules and compare their ratios to liquid water that is found in its natural state.
Of particular interest is Mars’ north and south poles where icecaps containing water and carbon dioxide ice persist to modern times. The water those icecaps contain is thought to document the evolution of water since the red planet’s wet Noachian period (approximately 3.7 billion years ago) to today. It turns out that the water measured in these polar regions is enriched with HDO by a factor of 7 when compared with water in Earth’s oceans. This, according to the study, indicates that Mars has lost a volume of water 6.5 times larger than the water currently contained within the modern-day icecaps.
Therefore, the volume of Mars’ early ocean must have been at least 20 million cubic kilometers, writes the news release.
Taking into account the Martian global terrain, most of the water would have been concentrated around the northern plains, a region dominated by low-lying land. An ancient ocean, with this estimate volume of water, would have covered 19 percent of the Martian globe, a significant area considering the Atlantic Ocean covers 17 percent of the Earth’s surface.
“With Mars losing that much water, the planet was very likely wet for a longer period of time than previously thought, suggesting the planet might have been habitable for longer,” said Michael Mumma, also of NASA’s Goddard Space Flight Center.
This estimate is likely on the low-side as Mars is thought to contain significant quantities of water ice below its surface — a fact that surveys such as this can be useful for pinpointing exactly where the remaining water may be hiding.
Ulli Kaeufl, of the European Southern Observatory and co-author of the paper, added: “I am again overwhelmed by how much power there is in remote sensing on other planets using astronomical telescopes: we found an ancient ocean more than 100 million kilometers away!”
Source: ESO
But how much water did Mars possess? According to research published in the journal Science, the Martian northern hemisphere was likely covered in an ocean, covering a region of the approximate area as Earth’s Atlantic Ocean, plunging, in some places, to 1.6 kilometers (1 mile) deep.
“Our study provides a solid estimate of how much water Mars once had, by determining how much water was lost to space,” said Geronimo Villanueva, of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the new paper, in an ESO news release. “With this work, we can better understand the history of water on Mars.”
Over a 6-year period, Villanueva and his team used the ESO’s Very Large Telescope (in Chile) and instruments at the W. M. Keck Observatory and the NASA Infrared Telescope Facility (both on Mauna Kea in Hawaii) to study the distribution of water molecules in the Martian atmosphere. By building a comprehensive map of water distribution and seasonal changes, they were able to arrive at this startling conclusion.
It is becoming clear that, over the aeons, Mars lost the majority of its atmosphere to space. That also goes for its water. Though large quantities of water were likely frozen below the surface as the atmosphere thinned and cooled, the water contained in an ocean of this size must have gone elsewhere — it must have also been lost to space.
This artist’s impression shows how Mars may have looked about four billion years ago. The young planet Mars would have had enough water to cover its entire surface in a liquid layer about 140 meters deep, but it is more likely that the liquid would have pooled to form an ocean occupying almost half of Mars’s northern hemisphere.
Also known as “semi-heavy water,” HDO is less susceptible to being evaporated away and being lost to space, so logic dictates that if water is boiled (or sublimated) away on Mars, the H2O molecules will be preferentially lost to space whereas a higher proportion of HDO will be left behind.
By using powerful ground-based observatories, the researchers were able to determine the distribution of HDO molecules and the H2O molecules and compare their ratios to liquid water that is found in its natural state.
Of particular interest is Mars’ north and south poles where icecaps containing water and carbon dioxide ice persist to modern times. The water those icecaps contain is thought to document the evolution of water since the red planet’s wet Noachian period (approximately 3.7 billion years ago) to today. It turns out that the water measured in these polar regions is enriched with HDO by a factor of 7 when compared with water in Earth’s oceans. This, according to the study, indicates that Mars has lost a volume of water 6.5 times larger than the water currently contained within the modern-day icecaps.
Therefore, the volume of Mars’ early ocean must have been at least 20 million cubic kilometers, writes the news release.
Taking into account the Martian global terrain, most of the water would have been concentrated around the northern plains, a region dominated by low-lying land. An ancient ocean, with this estimate volume of water, would have covered 19 percent of the Martian globe, a significant area considering the Atlantic Ocean covers 17 percent of the Earth’s surface.
“With Mars losing that much water, the planet was very likely wet for a longer period of time than previously thought, suggesting the planet might have been habitable for longer,” said Michael Mumma, also of NASA’s Goddard Space Flight Center.
This estimate is likely on the low-side as Mars is thought to contain significant quantities of water ice below its surface — a fact that surveys such as this can be useful for pinpointing exactly where the remaining water may be hiding.
Ulli Kaeufl, of the European Southern Observatory and co-author of the paper, added: “I am again overwhelmed by how much power there is in remote sensing on other planets using astronomical telescopes: we found an ancient ocean more than 100 million kilometers away!”
Source: ESO
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| Archaeologists in Honduras have found dozens of artifacts at a site where they believe twin cities stood. Photograph: Dave Yoder/National Geographic |
Archaeological team say they have set foot in a place untouched by humans for at least 600 years in a site that may be the ‘lost city of the monkey god’
Archaeologists have discovered two lost cities in the deep jungle of Honduras, emerging from the forest with evidence of a pyramid, plazas and artifacts that include the effigy of a half-human, half-jaguar spirit.
The team of specialists in archaeology and other fields, escorted by three British bushwhacking guides and a detail of Honduran special forces, explored on foot a remote valley of La Mosquitia where an aerial survey had found signs of ruins in 2012.
Chris Fisher, the lead US archaeologist on the team, told the Guardian that the expedition – co-coordinated by the film-makers Bill Benenson and Steve Elkins, Honduras and National Geographic (which first reported the story on its site) – had by all appearances set foot in a place that had gone untouched by humans for at least 600 years.
“Even the animals acted as if they’ve never seen people,” Fisher said. “Spider monkeys are all over place, and they’d follow us around and throw food at us and hoot and holler and do their thing.”
“To be treated not as a predator but as another primate in their space was for me the most amazing thing about this whole trip,” he said.
Fisher and the team arrived by helicopter to “groundtruth” the data revealed by surveying technology called Lidar, which projects a grid of infrared beams powerful enough to break through the dense forest canopy.
In the rainforest valley, they said they found stone structural foundations of two cities that mirrored people’s thinking of the Maya region, though these were not Mayan people. The area dates between 1000AD and 1400AD, and while very little is known without excavation of the site and surrounding region, Fisher said it was likely that European diseases had at least in part contributed to the culture’s disappearance.
The expedition also found and documented 52 artifacts that Virgilio Paredes, head of Honduras’s national anthropology and history institute, said indicated a civilisation distinct from the Mayans. Those artifacts included a bowl with an intricate carvings and semi-buried stone sculptures, including several that merged human and animal characteristics.
The cache of artifacts – “very beautiful, very fantastic,” in Fisher’s words – may have been a burial offering, he said, noting the effigies of spirit animals such as vultures and serpents.
Fisher said that while an archaeologist would likely not call these cities evidence of a lost civilisation, he would call it evidence of a culture or society. “Is it lost? Well, we don’t know anything about it,” he said.
The exploratory team did not have a permit to excavate and hopes to do so on a future expedition. “That’s the problem with archaeology is it takes a long time to get things done, another decade if we work intensively there, but then we’ll know a little more,” Fisher said.
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Despite the abundance of monkeys, far too little is known of the site still to tie it to the “lost city of the monkey god” that one such expedition claimed to have discovered. In about 1940, the eccentric journalist Theodore Morde set off into the Honduran jungle in search of the legendary “white city” that Spanish conquistadors had heard tales of in the centuries before.
He broke out of the brush months later with hundreds of artifacts and extravagant stories of how ancient people worshipped their simian deity. According to Douglas Preston, the writer National Geographic sent along with its own expedition: “He refused to divulge the location out of fear, he said, that the site would be looted. He later committed suicide and his site – if it existed at all – was never identified.”
Fisher emphasised that archaeologists know extraordinarily little about the region’s ancient societies relative to the Maya civilisation, and that it would take more research and excavation. He said that although some academics might find it distasteful, expeditions financed through private means – in this case the film-makers Benenson and Elkins – would become increasingly commonplace as funding from universities and grants lessened.
Fisher also suggested that the Lidar infrared technology used to find the site would soon be as commonplace as radiocarbon dating: “People just have to get through this ‘gee-whiz’ phase and start thinking about what we can do with it.”
Paredes and Fisher also said that the pristine, densely-wooded site was dangerously close to land being deforested for beef farms that sell to fast-food chains. Global demand has driven Honduras’s beef industry, Fisher said, something that he found worrying.
“I keep thinking of those monkeys looking at me not having seen people before. To lose all this over a burger, it’s a really hard pill to swallow.”
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| Frank Drake, the founder of Search for Extraterrestrial Intelligence (SETI), at his home in Aptos, Calif. (Ramin Rahimian for The Washington Post) |
Excerpt from washingtonpost.com
It was near Green Bank, W.Va., in 1960 that a young radio astronomer named Frank Drake conducted the first extensive search for alien civilizations in deep space. He aimed the 85-foot dish of a radio telescope at two nearby, sun-like stars, tuning to a frequency he thought an alien civilization might use for interstellar communication.
But the stars had nothing to say.
So began SETI, the Search for Extraterrestrial Intelligence, a form of astronomical inquiry that has captured the imaginations of people around the planet but has so far failed to detect a single “hello.” Pick your explanation: They’re not there; they’re too far away; they’re insular and aloof; they’re zoned out on computer games; they’re watching us in mild bemusement and wondering when we’ll grow up.
Now some SETI researchers are pushing a more aggressive agenda: Instead of just listening, we would transmit messages, targeting newly discovered planets orbiting distant stars. Through “active SETI,” we’d boldly announce our presence and try to get the conversation started.
Naturally, this is controversial, because of . . . well, the Klingons. The bad aliens.
NASA discovers first Earth-size planet in habitable zone of another star
"NASA's Kepler Space Telescope has discovered the first validated Earth-size planet orbiting in the habitable zone of a distant star, an area where liquid water might exist on its surface. The planet, Kepler-186f, is ten percent larger in size than Earth and orbits its parent star, Kepler-186, every 130 days. The star, located about 500 light-years from Earth, is classified as an M1 dwarf and is half the size and mass of our sun." (NASA Ames Research Center)
This objection is moot, however, according to the proponents of active SETI. They argue that even if there are unfriendlies out there, they already know about us. That’s because “I Love Lucy” and other TV and radio broadcasts are radiating from Earth at the speed of light. Aliens with advanced instruments could also detect our navigational radar beacons and would see that we’ve illuminated our cities.
“We have already sent signals into space that will alert the aliens to our presence with the transmissions and street lighting of the last 70 years,” Seth Shostak, an astronomer at the SETI Institute in California and a supporter of the more aggressive approach, has written. “These emissions cannot be recalled.”
That’s true only to a point, say the critics of active SETI. They argue that unintentional planetary leakage, such as “I Love Lucy,” is omnidirectional and faint, and much harder to detect than an intentional, narrowly focused signal transmitted at a known planet.
(Reuters) - A 2.8-million-year-old jawbone fossil with five intact teeth unearthed in an Ethiopian desert is pushing back the dawn of humankind by about half a million years.Scientists said on Wednesday the fossil represents the oldest known repres...
Excerpt from space.com
by Mike Wall
Is it time to take the search for intelligent aliens to the next level?
For more than half a century, scientists have been scanning the heavens for signals generated by intelligent alien life. They haven't found anything conclusive yet, so some researchers are advocating adding an element called "active SETI" (search for extraterrestrial intelligence) — not just listening, but also beaming out transmissions of our own designed to catch aliens' eyes.
Active SETI "may just be the approach that lets us make contact with life beyond Earth," Douglas Vakoch, director of interstellar message composition at the SETI Institute in Mountain View, California, said earlier this month during a panel discussion at the annual meeting of the American Association for the Advancement of Science (AAAS) in San Jose.
Seeking contact
Vakoch envisions using big radio dishes such as the Arecibo Observatory in Puerto Rico to blast powerful, information-laden transmissions at nearby stars, in a series of relatively cheap, small-scale projects.
"Whenever any of the planetary radar folks are doing their asteroid studies, and they have an extra half an hour before or after, there's always a target star readily available that they can shift to without a lot of extra slough time," he said.
The content of any potential active SETI message is a subject of considerable debate. If it were up to astronomer Seth Shostak, Vakoch's SETI Institute colleague, we'd beam the entire Internet out into space.
"It's like sending a lot of hieroglyphics to the 19th century — they [aliens] can figure it out based on the redundancy," Shostak said during the AAAS discussion. "So, I think in terms of messages, we should send everything."
While active SETI could help make humanity's presence known to extrasolar civilizations, the strategy could also aid the more traditional "passive" search for alien intelligence, Shostak added.
"If you're going to run SETI experiments, where you're trying to listen for a putative alien broadcast, it may be very instructive to have to construct a transmitting project," he said. "Because now, you walk a mile in the Klingons' shoes, assuming they have them."
Cause for concern?
But active SETI is a controversial topic. Humanity has been a truly technological civilization for only a few generations; we're less than 60 years removed from launching our first satellite to Earth orbit, for example. So the chances are that any extraterrestrials who pick up our signals would be far more advanced than we are.This likelihood makes some researchers nervous, including famed theoretical physicist Stephen Hawking.
"Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they could reach," Hawking said in 2010 on an episode of "Into the Universe with Stephen Hawking," a TV show that aired on the Discovery Channel. "If so, it makes sense for them to exploit each new planet for material to build more spaceships so they could move on. Who knows what the limits would be?"
Astrophysicist and science fiction author David Brin voiced similar concerns during the AAAS event, saying there's no reason to assume that intelligent aliens would be altruistic.
"This is an area in which discussion is called for," Brin said. "What are the motivations of species that they might carry with them into their advanced forms, that might color their cultures?"
Brin stressed that active SETI shouldn't be done in a piecemeal, ad hoc fashion by small groups of astronomers.
"This is something that should be discussed worldwide, and it should involve our peers in many other specialties, such as history," he said. "The historians would tell us, 'Well, gee, we have some examples of first-contact scenarios between advanced technological civilizations and not-so-advanced technological civilizations.' Gee, how did all of those turn out? Even when they were handled with goodwill, there was still pain."
Out there already
Vakoch and Shostak agreed that international discussion and cooperation are desirable. But Shostak said that achieving any kind of consensus on the topic of active SETI may be difficult. For example, what if polling reveals that 60 percent of people on Earth are in favor of the strategy, while 40 percent are opposed?"Do we then have license to go ahead and transmit?" Shostak said. "That's the problem, I think, with this whole 'let's have some international discussion' [idea], because I don't know what the decision metric is."
Vakoch and Shostak also said that active SETI isn't as big a leap as it may seem at first glance: Our civilization has been beaming signals out into the universe unintentionally for a century, since the radio was invented.
"The reality is that any civilization that has the ability to travel between the stars can already pick up our accidental radio and TV leakage," Vakoch said. "A civilization just 200 to 300 years more advanced than we are could pick up our leakage radiation at a distance of several hundred light-years. So there are no increased dangers of an alien invasion through active SETI."
But Brin disputed this assertion, saying the so-called "barn door excuse" is a myth.
"It is very difficult for advanced civilizations to have picked us up at our noisiest in the 1980s, when we had all these military radars and these big television antennas," he said.
Shostak countered that a fear of alien invasion, if taken too far, could hamper humanity's expansion throughout the solar system, an effort that will probably require the use of high-powered transmissions between farflung outposts.
"Do you want to hamstring all that activity — not for the weekend, not just shut down the radars next week, or active SETI this year, but shut down humanity forever?" Shostak said. "That's a price I'm not willing to pay."
So the discussion and debate continues — and may continue for quite some time.
"This is the only really important scientific field without any subject matter," Brin said. "It's an area in which opinion rules, and everybody has a very fierce opinion."
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| Mercury's extreme temperatures and lack of an atmosphere would make it very difficult, if not impossible, for people to live on the planet. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
Excerpt from space.com
By Joseph Castro, Space.com Contributor
Have you ever wondered what it might be like to homestead on Mars or walk on the moons of Saturn? So did we. This is the first in Space.com's 12-part series on what it might be like to live on or near planets in our solar system, and beyond. Check back each week for the next space destination.
With its extreme temperature fluctuations, Mercury is not likely a planet that humans would ever want to colonize. But if we had the technology to survive on the planet closest to the sun, what would it be like to live there?To date, only two spacecraft have visited Mercury. The first, Mariner 10, conducted a series of Mercury flybys in 1974, but the spacecraft only saw the lit half of the planet. NASA's MESSENGER spacecraft, on the other hand, conducted flybys and then entered Mercury's orbit — in March of 2013, images from the spacecraft allowed scientists to completely map the planet for the first time.
MESSENGER photos of Mercury show that the planet has water ice at its poles, which sit in permanent darkness. Mining this ice would be a good way to live off the land, but setting up bases at the poles might not be a good idea, said David Blewett, a participating scientist with the Messenger program.
"The polar regions would give you some respite from the strength of the sun on Mercury," Blewett told Space.com. "But, of course, it's really cold in those permanently shadowed areas where the ice is, and that presents its own challenge."
A better option, he said, would probably be to set up a home base not far from one of the ice caps, perhaps on a crater rim, and have a water mining operation at the pole.
Still, dealing with extreme temperatures on Mercury would likely be unavoidable: Daytime temperatures on the planet can reach 800 degrees Fahrenheit (430 degrees Celsius), while nighttime temperatures can drop down to minus 290 degrees Fahrenheit (minus 180 degrees Celsius).
Scientists once believed Mercury was tidally locked with the sun, meaning that one side of the planet always faces the sun because it takes the same amount of time to rotate around its axis as it does to revolve around the star. But we now know that Mercury's day lasts almost 59 Earth days and its year stretches for about 88 Earth days.
Interestingly, the sun has an odd path through the planet's sky over the course of Mercury's long day, because of the interaction between Mercury's spin rate and its highly elliptical orbit around the sun.
"It [the sun] rises in the east and moves across the sky, and then it pauses and moves backwards just a tad. It then resumes its motion towards the west and sunset," said Blewett, adding that the sun appears 2.5 times larger in Mercury's sky than it does in Earth's sky.
And during the day, Mercury's sky would appear black, not blue, because the planet has virtually no atmosphere to scatter the sun's light. "Here on Earth at sea level, the molecules of air are colliding billions of times per second," Blewett said. "But on Mercury, the atmosphere, or 'exosphere,' is so very rarefied that the atoms essentially never collide with other exosphere atoms." This lack of atmosphere also means that the stars wouldn't twinkle at night.
But Mercury isn't devoid of natural disasters. "The surface is exposed to impacts of all sizes," Blewett said. It also may suffer from earthquakes due to compressive forces that are shrinking the planet (unlike Earth, Mercury doesn't have tectonic activity).
Mercury is about two-fifths the size of Earth, with a similar gravity to Mars, or about 38 percent of Earth's gravity. This means that you could jump three times as high on Mercury, and heavy objects would be easier to pick up, Blewett said. However, everything would still have the same mass and inertia, so you could be knocked over if someone threw a heavy object at you, he added.
Finally, you can forget about a smooth Skype call home: It takes at least 5 minutes for signals from Mercury to reach Earth, and vice versa.
The Icarus Interstellar 'Firefly' starship concept could use novel nuclear fusion techniques to power its way to Alpha Centauri within 100 years.Adrian MannExcerpt from news.discovery.com As part of Icarus Interstellar's continuing series ...
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.
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)
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.
Excerpt from washingtonpost.com
Chronic fatigue syndrome is a "serious, debilitating" condition with a cluster of clear physical symptoms — not a psychological illness — a panel of experts reported Tuesday as it called for more research into a disease that may affect as many as 2.5 million Americans.
"We just needed to put to rest, once and for all, the idea that this is just psychosomatic or that people were making this up, or that they were just lazy," said Ellen Wright Clayton, a professor of pediatrics and law at Vanderbilt University, who chaired the committee of the Institute of Medicine, the health arm of the National Academy of Sciences.
Although the cause of the disorder is still unknown, the panel established three critical symptoms for the condition (also known as myalgic encephalomyelitis):
- A sharp reduction in the ability to engage in pre-illness activity levels that lasts for more than six months and is accompanied by deep fatigue that only recently developed.
- Worsening of symptoms after any type of exertion, including "physical, cognitive or emotional stress."
- Sleep that doesn't refresh the sufferer.
The panel acknowledged what people with chronic fatigue syndrome have long complained about: They struggle, sometimes for years, before finding a health-care provider who diagnoses a disorder that often devastates their lives. Sixty-seven percent to 77 percent reported in surveys that it took longer than a year to receive a diagnosis, and about 29 percent said it took longer than five years. The vast majority of people with the disorder remain undiagnosed, the panel said, estimating that between 836,000 and 2.5 million Americans have it.
"Seeking and receiving a diagnosis can be a frustrating process for several reasons, including skepticism of health care providers about the serious nature of [chronic fatigue syndrome] and the misconception that it is a psychogenic illness or even a figment of the patient’s imagination," the panel wrote. Less than a third of medical schools include the condition in their curricula and only 40 percent of medical textbooks contain information on it, the experts said.
Christine Williams, who has the illness herself and is vice-chair of the board of directors for the advocacy group Solve ME/CFS Initiative, welcomed the IOM report.
“I have been sick for six-and-a-half-years, and this is definitely the most encouraging thing that I have seen,” she said. Williams praised the IOM for setting forth a set of clearly understandable diagnostic criteria, including the hallmark symptom “post-exertional malaise.”
Williams predicted that the IOM panel’s proposed new name for the illness -- "systemic exertion intolerance disease"--would be widely debated by patients’ groups. But she added that the IOM “moved in the right direction by getting away from 'chronic fatigue syndrome',” which she said trivialized a serious disease.
Williams, who spent three decades working as a health policy expert in the federal government, said she hopes the report sparks additional research into new treatments for the illness.
The cause of chronic fatigue syndrome remains unknown, but symptoms may be triggered by an infection or "immunization, anesthetics, physical trauma, exposure to environmental pollutants, chemicals and heavy metals and, rarely, blood transfusions," the panel reported. Clayton said mononucleosis is "a major trigger" of chronic fatigue syndrome among adolescents, but little is known about causes beyond that.
Treatments can include drugs such as anti-depressants and sleeping pills; gentle exercise and psychological counseling; and lifestyle changes such as limiting stress, caffeine, nicotine and alcohol.
Clayton also emphasized that many people with chronic fatigue syndrome also have other medical problems, which can complicate diagnosis and treatment.
"Lots of adults have more than one thing going on," she said. "If they meet these criteria, they have this disorder. They can have something else as well, which is not uncommon in medicine."
Excerpt from cnet.com Though the seismic waves from earthquakes are best known for their destructive abilities, in the hands of geologists, they can be powerful tools of discovery. A research team at the University of Illinois (UI) has just used th...
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These sulfur bacteria haven't evolved for billions of years. |
Excerpt from natmonitor.com
By Justin Beach
If there was a Guinness World Record for not evolving, it would be held by a sulfur-cycling microorganism found off the course of Australia. According to research published in the Proceedings of the National Academy of Sciences, they have not evolved in any way in more than two billion years and have survived five mass extinction events.
According to the researchers behind the paper, the lack of evolution actually supports Charles Darwin’s theory of evolution by natural selection.
The researchers examined the microorganisms, which are too small to see with the naked eye, in samples of rocks from the coastal waters of Western Australia. Next they examined samples of the same bacteria from the same region in rocks 2.3 billion years old. Both sets of bacteria are indistinguishable from modern sulfur bacteria found off the coast of Chile.
Critics of Darwin’s theory of evolution might be tempted to jump on this discovery as proof that Darwin was wrong, but that would be a mistake.
Darwin’s work focused more on species that changed, rather than species that didn’t. However, there is nothing in Darwin’s work that states that a successful species that has found it’s niche in an ecosystem has to change. Unless there is change in the ecosystem or competition for resources there would be no reason for change.
“The rule of biology is not to evolve unless the physical or biological environment changes, which is consistent with Darwin. These microorganisms are well-adapted to their simple, very stable physical and biological environment. If they were in an environment that did not change but they nevertheless evolved, that would have shown that our understanding of Darwinian evolution was seriously flawed.” said Schopf, who also is director of UCLA’s Center for the Study of Evolution and the Origin of Life.
It is likely that there were genetic mutations in the organisms. Mutations are fairly random and happen in all species, but unless those mutations are improvements that help the species function better in the environment, they usually do not get passed on.
Schopf said that the findings provide further proof that Darwin’s ideas were right.
The oldest fossils analyzed for the study date back to the Great Oxidation Event. This event, which occurred between 2.2 and 2.4 billion years ago, saw a substantial increase in Earth’s oxygen levels. That period also saw an increase in sulfates and nitrates, which is all that the microorganisms would have needed to survive and reproduce.
Shopf and his team used Raman spectroscopy, which allows scientists to examine the composition and chemistry of rocks as well as confocal laser scary microscopy to generate 3-D images of fossils embedded in rock.
The research was funded by NASA Astrobiology Institute, in the hope that it will help the space agency to find life elsewhere.
Excerpt from pressofatlanticcity.comBy FRED SCHAAF ...
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