Viewpoint: Should we send humans to Mars?
|4:42:40 AM, Wednesday, October 10, 2012|
"(BBC 21 September 2012) In the second instalment of his two-part feature on human missions to Mars, Dr Alexander Kumar - who has been overwintering at Concordia Station, Antarctica - asks whether we should send people to the Red Planet given our poor record managing this one. Read the first part here.
Much like the interior of Antarctica, Mars remains inhospitable.
For humans to live on the planet for any significant period of time would require the recycling of water and air, along with other so-called "life systems".
At Concordia station in Antarctica (my current home) we use "grey water recycling" - taking the water generated from domestic activities such as laundry, bathing and dishwashing and recycling it on-site for other uses. This mirrors the system used on the International Space Station (ISS).
But there are even grander ideas that could further extend the duration of human habitation on Mars.
Whether or not we find Martian life, there is a long-standing wish to "terraform" the Red Planet. This would involve artificially transforming the climate and surface to enable humans to live there without life support systems.
In his Mars Trilogy, science fiction author Kim Stanley Robinson documents the process of inhabitation and colonisation, causing a chain of events that turn the Red Planet into a green one and later a blue world.
A human presence on Mars will inevitably change the environment. It was HG Wells who first identified the possibility of humans unknowingly "spoiling" other distant planets through bio-contamination - bringing their bacteria and other potential microbial colonists with them.
I believe the lessons we have learnt in the past century through polar - and in particular Antarctic -exploration and science are very relevant. Our delicate polar regions are continually threatened by climate change and so often used to forecast and track the state of our planet.
Mr Robinson maintains that when it comes to investigating the challenges of sending a manned mission to Mars "Antarctica is the best analogue, not the Wild West or anything else".
John Ash from the Scott Polar Research Institute commented: "Forward contamination is a critical factor in space exploration, and much may be learned by the work being done in connection with the penetration of Antarctica's hidden ice lakes. Of course, it is critical not to contaminate samples that may offer scientific proof of extraterrestrial life; but there are also legal obligations."
He is referring to the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies.
Alongside the potential for "forward" contamination, our own contamination of the new, previously undisturbed environments we visit, there is the potential of "backward" contamination also.
There are many other ideas - methods employed by past polar explorers using a depot system to cross Antarctica's empty, hostile and unknown interior, could be adapted to a manned mission to Mars, where a series of supply depots could be laid in orbit between Earth and Mars, accompanied by sending reserve supplies equipment into Mars' orbit or to a planned landing site on its surface.
Like the polar expeditions led by Amundsen, Scott and Shackleton, this would add a factor of safety, reassurance and ability to resupply and makes repairs en-route, for the brave crew travelling into the unknown.
Over the coming decades, there could be another call for astronauts, this time for a manned mission to Mars. Similar to Ernest Shackleton's fabled newspaper advertisement, with Nasa's recent budgetary cuts, recruitment for an interplanetary mission's crew might also spell out: "Men and women wanted for hazardous journey, small wages, bitter cold and long months of complete darkness."
The late science fiction writer Ray Bradbury left us with an echoic and stern warning in his story The Martian Chronicles where the colonisation of Mars becomes a necessity for human survival - with humans fleeing a troubled, broken and atomically devastated home planet Earth.
If our species follows its current course, a biblical apocalypse could be a potential outcome.
In describing the possibility of standing on the surface of Mars himself, Tim Peake tells me: "It would be the most exhilarating feeling imaginable."
He adds: "At some point, hopefully many, many years in the future, the Earth will suffer an event that human life cannot tolerate - that is to say, an extinction event.
"If mankind is to survive as a species then in the long term our future existence lies in colonisation of other planets or moons. I believe this is something that can be achieved, but it will require many years of progressive steps before we are capable of colonisation.
"We live on a fragile planet in a highly dynamic Universe, so manned exploration of space is not just about our quest for knowledge but also an insurance policy for the future."
Many sceptics will undoubtedly question why any country would choose to invest in future space exploration, including a manned mission to Mars, while there are so many unsolved problems on our planet, from HIV to malaria to poverty.
They would be absolutely correct. Trust me, I'm a doctor who has travelled far and wide, and have witnessed the worst effects of poverty, disease and war.
The last words of Captain Robert Falcon Scott, addressed to the public in his diary, echo loudly: "For God's sake look after our people."
Sitting in Antarctica 100 years on, dreaming of Mars, I would update Scott's advice by factoring into his equation, the impact (unbeknown to him) of humans on Earth over the past century.
I would reiterate: "For God's sake, look after our people…. and also our planet."
Caring is sharing
Should we be so frivolous by our excessive nature, and be trusted to visit, contaminate and perhaps colonise another planet when we seem so incapable of conserving and looking after our own home world?
Maybe this continuing lack of care for the planet and its people will one day become the reason we leave Earth for once and for all.
However, alongside my experiences as a doctor, I also travel the world as a scientific explorer.
On a large lonely wooden cross on top of a hill in Antarctica, overlooking a route taken to the South Pole, someone inscribed the words "to strive, to seek, to find and not to yield".
These words, borrowed from Sir Alfred Tennyson's Ulysses poem, had been left by the party who located Scott's tent in memory of the expedition team's legacy.
Among them, my own hero, the doctor Edward Wilson, whose dreams did not become a graveyard leave a blazing trail and legacy of science to inspire future generations.
Only by pushing mankind to its limits, to the bottoms of the ocean and into space, will we make discoveries in science and technology that can be adapted to improve life on Earth.
If the origin of life as we know it arose from a Big Bang in a distant area of the Universe, perhaps the solutions we seek to our problems on Earth may also lie there.
Failing to strive, seek or find would be an even greater tragedy - and represent a giant leap backwards for mankind."
Yangtze dolphin's decline mirrored by other animals
|4:33:07 AM, Wednesday, October 10, 2012|
"(Phys.org August 13, 2012) Monitoring numbers of the baiji, the now-extinct freshwater dolphin of the Yangtze river, would also have let researchers track the decline of other threatened animals, including the Yangtze paddlefish and Reeves' shad, a new study shows.
A disproportionate amount of public attention and conservation resources tend to go towards big, impressive animals like the baiji, and the paper – published in PLoS ONE – suggests that conservationists could take advantage of this; research on these creatures could be used indirectly to shed light on the population trends of their less media-friendly neighbours.
The idea that so-called 'charismatic megafauna' like whales and tigers could provide an index of the overall health of their environment isn't new, but it's proved difficult to demonstrate in a rigorous way.
Dr Samuel Turvey of the Institute of Zoology repeatedly travelled to China over the last few years to interview fishermen on the Yangtze about when they last saw various threatened species including the baiji. It's become clear that the baiji is now extinct, but analysing the results of these interviews shows not only that the paddlefish and shad have both declined and may also be extinct, but also that the curves representing their plummeting numbers match that of the baiji very closely.
This was a surprise, as the three animals filled very different ecological niches and on the face of things might be expected to react differently to the same threats and environmental pressures.
'There was no reason to think that these species would have similar patterns of decline over time - they're very different in their ecology and in how they were exploited, although we know that all three were affected by fisheries,' Turvey says. 'There's very little information on the shad and the paddlefish, so we can only infer the pattern of their declines retrospectively - we've only found out what happened to them when it's already too late. Conservation resources are limited and are likely to be focused on charismatic animals, but because the status of such animals can match that of other species, we can at least try to get as much benefit as possible from that.'
One common thread is that all three species used to migrate up and down the river to get to better feeding or breeding grounds, so their reproductive cycles were more easily disrupted by barriers like dams that blocked their passage. They also all suffered badly from overfishing, as well as pollution and other environmental problems. Other non-migratory animals, such as members of the carp and catfish families, are still relatively common in the Yangtze despite its degraded state.
On the other hand, changes in the frequency of sightings of the finless porpoise, another large aquatic mammal that still survives in the Yangtze, weren't linked to those of the other animals.
Turvey isn't sure why. The porpoise isn't migratory, so it doesn't share the feature that could have contributed to the other three species' increased vulnerability. He suggests that because porpoises are still encountered by fishermen fairly regularly, it's harder to document changes to the state of their population using last-sighting reports.
The porpoise is also highly threatened and is declining too, but Turvey is hopeful that efforts to protect it will be more effective than they were for the baiji. Because the river ecosystem has been damaged so badly, the best hope for protecting animals is to set up reserves away from the main river, where animals can be protected and won't face the same fierce environmental pressures. Efforts to do this for the baiji never got off the ground, whereas porpoise reserves are already in place and working well.
He adds that the research could be applied in other river ecosystems with big, media-friendly inhabitants, such as Ganges or Irawaddy dolphins."
Gold-loving bacteria show superman strength
|4:23:20 AM, Wednesday, October 10, 2012|
"(news.msu.edu 10/01/2012) EAST LANSING, Mich. — At a time when the value of gold has reached an all-time high, Michigan State University researchers have discovered a bacterium’s ability to withstand incredible amounts of toxicity is key to creating 24-karat gold.
“Microbial alchemy is what we’re doing – transforming gold from something that has no value into a solid, precious metal that’s valuable,” said Kazem Kashefi, assistant professor of microbiology and molecular genetics.
He and Adam Brown, associate professor of electronic art and intermedia, found the metal-tolerant bacteria Cupriavidus metallidurans can grow on massive concentrations of gold chloride – or liquid gold, a toxic chemical compound found in nature.
In fact, the bacteria are at least 25 times stronger than previously reported among scientists, the researchers determined in their art installation, “The Great Work of the Metal Lover,” which uses a combination of biotechnology, art and alchemy to turn liquid gold into 24-karat gold. The artwork contains a portable laboratory made of 24-karat gold-plated hardware, a glass bioreactor and the bacteria, a combination that produces gold in front of an audience.
Brown and Kashefi fed the bacteria unprecedented amounts of gold chloride, mimicking the process they believe happens in nature. In about a week, the bacteria transformed the toxins and produced a gold nugget.
“The Great Work of the Metal Lover” uses a living system as a vehicle for artistic exploration, Brown said.
In addition, the artwork consists of a series of images made with a scanning electron microscope. Using ancient gold illumination techniques, Brown applied 24-karat gold leaf to regions of the prints where a bacterial gold deposit had been identified so that each print contains some of the gold produced in the bioreactor.
“This is neo-alchemy. Every part, every detail of the project is a cross between modern microbiology and alchemy,” Brown said. “Science tries to explain the phenomenological world. As an artist, I’m trying to create a phenomenon. Art has the ability to push scientific inquiry.”
It would be cost prohibitive to reproduce their experiment on a larger scale, he said. But the researchers’ success in creating gold raises questions about greed, economy and environmental impact, focusing on the ethics related to science and the engineering of nature.
“The Great Work of the Metal Lover” was selected for exhibition and received an honorable mention at the world-renowned cyber art competition, Prix Ars Electronica, in Austria, where it’s on display until Oct. 7. Prix Ars Electronica is one of the most important awards for creativity and pioneering spirit in the field of digital and hybrid media, Brown said.
“Art has the ability to probe and question the impact of science in the world, and ‘The Great Work of the Metal Lover’ speaks directly to the scientific preoccupation while trying to shape and bend biology to our will within the postbiological age,” Brown said."
The $1 billion mission to reach the Earth's mantle
|4:18:27 AM, Wednesday, October 10, 2012|
"(CNN 10/01/2012) Humans have reached the moon and are planning to return samples from Mars, but when it comes to exploring the land deep beneath our feet, we have only scratched the surface of our planet.
This may be about to change with a $1 billion mission to drill 6 km (3.7 miles) beneath the seafloor to reach the Earth's mantle -- a 3000 km-thick layer of slowly deforming rock between the crust and the core which makes up the majority of our planet -- and bring back the first ever fresh samples.
It could help answer some of our biggest questions about the origins and evolution of Earth itself, with almost all of the sea floor and continents that make up the Earth´s surface originating from the mantle.
Geologists involved in the project are already comparing it to the Apollo Moon missions in terms of the value of the samples it could yield.
However, in order to reach those samples, the team of international scientists must first find a way to grind their way through ultra-hard rocks with 10 km-long (6.2 miles) drill pipes -- a technical challenge that one of the project co-leaders Damon Teagle, from the UK's University of Southampton calls, "the most challenging endeavor in the history of Earth science."
Their task will be all the more difficult for being conducted out in the middle of the ocean. It is here that the Earth´s crust is at its thinnest at around 6 km compared to as much as 60 km (37.3 miles) on land.
They have already identified three possible locations -- all in the Pacific Ocean -- where the ocean floor was formed at relatively fast spreading mid-ocean ridges, says Teagle.
The hole they will drill will be just 30 cm in width all the way from the ocean floor to inside the mantle -- a monumental engineering feat.
"It will be the equivalent of dangling a steel string the width of a human hair in the deep end of a swimming pool and inserting it into a thimble 1/10 mm wide on the bottom, and then drilling a few meters into the foundations," says Teagle.
To get to the mantle scientists will be relying on a purpose-built Japanese deep-sea drilling vessel called Chikyu, first launched in 2002 and capable of carrying 10 km of drilling pipes. It has already set a world-record for the deepest hole in scientific ocean drilling history, reaching 2.2 km into the seafloor..."
Tomb of Maya Queen Found - 'Lady Snake Lord' Ruled Centipede Kingdom
|4:29:20 AM, Tuesday, October 09, 2012|
"(National Geographic 10/04/2012) The suspected tomb and remains of a great Maya warrior queen have been discovered in Guatemala, archaeologists say.
Uncovered at the site of the ancient city of El Perú-Waka', the tomb has been identified as likely belonging to Lady K'abel, military ruler of the Wak, or "Centipede," kingdom between A.D. 672 and 692.
The tomb was found this year in the ruins of the city's main pyramid temple during excavations led by archaeologist David Freidel of Washington University in St. Louis.
The body inside was buried with various offerings, including ceramic vessels, jade jewelry, stone figurines, and, crucially, a small alabaster jar carved in the shape of a conch shell, out of which the carved head and arms of an old woman emerge.
Maya hieroglyphs on the back of the jar include the names "Lady Water Lily Hand" and "Lady Snake Lord," according to the study team.
Both names are thought to refer to Lady K'abel, who governed the Wak kingdom for her family, the empire-building Kan, or "Snake," dynasty, based in the Maya capital Calakmul in what's now Mexico.
While Lady K'abel ruled with her husband, K'inich Bahlam, her title of Kaloomte, or "supreme warrior," gave her higher authority than the king.
"Fair Chance" It's Maya Queen
Though the skeleton's poor condition has made the individual's age and gender difficult to determine, the skull's robust facial features fit with ancient carved portraits of the stern-looking Maya queen, the study team said.
A red spiny oyster shell placed on the body's lower torso also points to the tomb being hers: The queens of El Perú-Waka' typically wore such shells as girdle ornaments, the team noted.
David Stuart, a professor of Mesoamerican art and writing at the University of Texas at Austin, said it's difficult to identify "who's who in royal tombs, unless they literally write it on the wall or something."
Nevertheless, "for this find, I think there's a fair chance it's her," added Stuart, who wasn't involved in the study.
While it's possible that the alabaster jar was a gift from Lady K'abel that ended up in another's tomb, the interpretation of its hieroglyphs are "spot on," Stuart said.
Matching the names given to the queen in other Maya inscriptions, the hieroglyphs leave "no question it's the same woman" being referred to, he said.
Warrior Queen's Tomb Revered by Maya
The Snake dynasty had a policy of marrying off its princesses and noblewomen to kings of vassal states like the Wak kingdom, Stuart explained.
Women such as Lady K'abel were "the family connection to the great city to the north"—Calakmul, he added.
"They would show them on the monuments, and it would be part of the political symbolism of these local subject states."
El Perú-Waka', which covered about 1 square kilometer (0.4 square mile), was made up of temple pyramids, public plazas, palaces, and homes.
Hidden today beneath tropical rain forest, the once impressive buildings have been reduced to rubble mounds over the centuries.
The newfound royal tomb could explain why the Maya city remained a focus of reverence and ritual attention long after the collapse of the Wak kingdom.
The study team writes: "It is now clear to us that the golden age of the city, and the great queen and her husband who presided over it, were remembered and celebrated by ordinary people with their humble offerings and hopes for renewal of the future.""
Facebook May Be More Tempting Than Sex
|4:20:00 AM, Tuesday, October 09, 2012|
"(medicaldaily.com 10/8/2012) Checking a Facebook or Twitter account may be more tempting than sex and cigarettes, according to a new study.
Researchers at Chicago University's Booth Business School used BlackBerrys to record participants' willpower and desires over a week in a new study, soon to be published in the journal Psychological Science.
Investigators conducted an online poll of 250 participants in Germany and found that the desire to interact with others through tweets, photos and comments was stronger than sex and cigarettes.
Researchers messaged participants seven times a day over 14 hours for a week. Participants were then required to message back to report whether they were experiencing a desire at the moment or had experienced an urge within the last 30 minutes.
Lead author Wilhelm Hofmann believes that social media may be harder to resist because they are more readily accessible than other stimulants.
Hofmann also noted that social media may be more alluring than drugs because they are cheaper than alcohol and cigarettes.
"Desires for media may be comparatively harder to resist because of their high availability and also because it feels like it does not cost much to engage in these activities, even though one wants to resist," Hofmann said, according to the Guardian.
Researchers found that the more people tried to resist doing something, the greater their desire to do so.
Investigators also found that people were addicted to work and that work was harder for people to resist than sports, sex and spending money."
NASA's Swift Satellite Discovers a New Black Hole in Milky Way Galaxy
|2:56:07 AM, Tuesday, October 09, 2012|
"(ScienceDaily Oct. 5, 2012) NASA's Swift satellite recently detected a rising tide of high-energy X-rays from a source toward the center of our Milky Way galaxy. The outburst, produced by a rare X-ray nova, announced the presence of a previously unknown stellar-mass black hole.
"Bright X-ray novae are so rare that they're essentially once-a-mission events and this is the first one Swift has seen," said Neil Gehrels, the mission's principal investigator, at NASA's Goddard Space Flight Center in Greenbelt, Md. "This is really something we've been waiting for."
An X-ray nova is a short-lived X-ray source that appears suddenly, reaches its emission peak in a few days and then fades out over a period of months. The outburst arises when a torrent of stored gas suddenly rushes toward one of the most compact objects known, either a neutron star or a black hole.
The rapidly brightening source triggered Swift's Burst Alert Telescope twice on the morning of Sept. 16, and once again the next day.
Named Swift J1745-26 after the coordinates of its sky position, the nova is located a few degrees from the center of our galaxy toward the constellation Sagittarius. While astronomers do not know its precise distance, they think the object resides about 20,000 to 30,000 light-years away in the galaxy's inner region.
Ground-based observatories detected infrared and radio emissions, but thick clouds of obscuring dust have prevented astronomers from catching Swift J1745-26 in visible light.
The nova peaked in hard X-rays -- energies above 10,000 electron volts, or several thousand times that of visible light -- on Sept. 18, when it reached an intensity equivalent to that of the famous Crab Nebula, a supernova remnant that serves as a calibration target for high-energy observatories and is considered one of the brightest sources beyond the solar system at these energies.
Even as it dimmed at higher energies, the nova brightened in the lower-energy, or softer, emissions detected by Swift's X-ray Telescope, a behavior typical of X-ray novae. By Wednesday, Swift J1745-26 was 30 times brighter in soft X-rays than when it was discovered and it continued to brighten.
"The pattern we're seeing is observed in X-ray novae where the central object is a black hole. Once the X-rays fade away, we hope to measure its mass and confirm its black hole status," said Boris Sbarufatti, an astrophysicist at Brera Observatory in Milan, Italy, who currently is working with other Swift team members at Penn State in University Park, Pa.
The black hole must be a member of a low-mass X-ray binary (LMXB) system, which includes a normal, sun-like star. A stream of gas flows from the normal star and enters into a storage disk around the black hole. In most LMXBs, the gas in the disk spirals inward, heats up as it heads toward the black hole, and produces a steady stream of X-rays..."
-- Follow the link below for the rest of the story, or click on the image!
The world’s shiniest living thing is an African fruit
|2:19:01 AM, Tuesday, October 09, 2012|
"(discoverymagazine.com 9/10/2012) In the forests of central Africa, there’s a plant that looks like it’s growing its own Christmas decorations. Shiny baubles sprout from between its leaves, shimmering in a vibrant metallic blue. Look closer, and other colours emerge – pinpricks of red, orange, green and violet. It looks as if Seurat, or some other pointillist painter, had turned their hand to sculpture.
But these spheres, of course, are no man-made creations. They’re fruit. They are the shiniest fruits in the world. Actually, they are the shiniest living materials in the world, full-stop.
They belong to a plant called Pollia condensata, a tropical metre-tall herb that sprouts its shiny berry-like fruits in clusters up to 40-strong. These little orbs are iridescent – they use special layers of cells, arranged just so, to reflect colours with extraordinary intensity. This trick relies on the microscopic physical structures of the cells, rather than on any chemical pigments. Indeed, the fruits have no blue pigment at all.
In the animal kingdom, such tricks are commonplace – you can see them at work on the wings of a butterfly, the shells of jewel beetles, or the feathers of pigeons, starlings, birds or paradise and even some dinosaurs. But in the plant world, pigments dominate and structural colours were thought to be non-existent are much rarer.
Silvia Vignolini from the University of Cambridge discovered Pollia’s secret at Kew Gardens in the UK. Her group, led by Ullrich Steiner, was scouring the plant world for species that bend light in interesting ways. Under the recommendation of the Smithsonian’s Robert Faden, Vognolini sought out Pollia, and with help from Kew’s Paula Rudall, she found a sample of the plant. It was collected from Ghana in 1974 but it’s still as vivid as ever. (Unlike pigments, structural colours don’t degrade, so the fruits will retain their sheen for decades to come. Some fossils still keep their iridescence.)
Under the microscope, Vignolini saw that the outer part of the fruit consists of three to four layers of thick-walled cells. Each cell contains yet more layers, made of cellulose fibres. The fibres all run parallel to one another, but each layer is slightly rotated against the one above it, producing an elegant spiral..."
Major advance made in generating electricity from wastewater
|2:03:22 AM, Tuesday, October 09, 2012|
"(phys.org August 13, 2012) Engineers at Oregon State University have made a breakthrough in the performance of microbial fuel cells that can produce electricity directly from wastewater, opening the door to a future in which waste treatment plants not only will power themselves, but will sell excess electricity.
The new technology developed at OSU can now produce 10 to 50 more times the electricity, per volume, than most other approaches using microbial fuel cells, and 100 times more electricity than some.
Researchers say this could eventually change the way that wastewater is treated all over the world, replacing the widely used "activated sludge" process that has been in use for almost a century. The new approach would produce significant amounts of electricity while effectively cleaning the wastewater.
The findings have just been published in Energy and Environmental Science, a professional journal, in work funded by the National Science Foundation.
"If this technology works on a commercial scale the way we believe it will, the treatment of wastewater could be a huge energy producer, not a huge energy cost," said Hong Liu, an associate professor in the OSU Department of Biological and Ecological Engineering. "This could have an impact around the world, save a great deal of money, provide better water treatment and promote energy sustainability."
Experts estimate that about 3 percent of the electrical energy consumed in the United States and other developed countries is used to treat wastewater, and a majority of that electricity is produced by fossil fuels that contribute to global warming.
But the biodegradable characteristics of wastewater, if tapped to their full potential, could theoretically provide many times the energy that is now being used to process them, with no additional greenhouse emissions.
OSU researchers reported several years ago on the promise of this technology, but at that time the systems in use produced far less electrical power. With new concepts – reduced anode-cathode spacing, evolved microbes and new separator materials – the technology can now produce more than two kilowatts per cubic meter of liquid reactor volume. This amount of power density far exceeds anything else done with microbial fuel cells..."
Speed of Universe's Expansion Measured Better Than Ever
|1:44:00 AM, Tuesday, October 09, 2012|
"(scientificamerican.com 10/04/2012) The newest measurements, courtesy of NASA's Spitzer Space Telescope, come from infrared observations of distant variable stars.
The universe just got a new speeding ticket.
The most precise measurement ever made of the speed of the universe's expansion is in, thanks to NASA's Spitzer Space Telescope, and it's a doozy. Space itself is pulling apart at the seams, expanding at a rate of 74.3 plus or minus 2.1 kilometers (46.2 plus or minus 1.3 miles) per second per megaparsec (a megaparsec is roughly 3 million light-years).
If those numbers are a little too much to contemplate, rest assured that's really, really fast. And it's getting faster all the time.
American astronomer Edwin P. Hubble first discovered that our universe isn't static in the 1920s. In fact, Hubble found, space has been expanding since it began with the Big Bang 13.7 billion years ago. Then, in the 1990s, astronomers shocked the world again with the revelation that this expansion is speeding up (this discovery won its finders the 2011 Nobel Prize in physics).
Ever since Hubble's initial discovery, scientists have been trying to refine their measurement of the universe's expansion rate, called the Hubble Constant. It's a hard measurement to make.
The new value reduces the uncertainty in the Hubble Constant to just 3 percent, and improves the precision of the measurement by a factor of three compared to a previous estimate from the Hubble Space Telescope.
"Just over a decade ago, using the words 'precision' and 'cosmology' in the same sentence was not possible, and the size and age of the universe was not known to better than a factor of two," Wendy Freedman of the Observatories of the Carnegie Institution for Science in Pasadena, Calif., said in a statement. "Now we are talking about accuracies of a few percent. It is quite extraordinary."
The new measurement doesn't just tell scientists how fast the universe is expanding, but helps shed light on the mystery of why this expansion is accelerating. Dark energy is the name given to whatever is causing the universe's expansion to speed up. Yet scientists have little idea what it is..."
Turkey strikes targets in Syria in retaliation for shelling deaths
|12:50:16 AM, Thursday, October 04, 2012|
"(CNN 2012/10/03) Turkey fired on Syrian government targets in response to the shelling of a Turkish border town in which five civilians were killed Wednesday, according to Prime Minister Recep Tayyip Erdogan's office.
The town of Akcakale "was hit by artillery fire belonging to the Syrian regime forces," a statement from Erdogan's office said, in the first clear assertion of blame for the shelling.
"Our armed forces on the border responded immediately to this atrocious attack within the rules of engagement, and points in Syria determined by radar were hit with artillery fire," it said. "Turkey, within the confines of the rules of engagement and international law, will never leave these types of provocations aimed at our national security unanswered."
The retaliatory artillery fire marks a significant increase in tension between the two countries, and CNN affiliate CNN Turk reported that witnesses observed intermittent artillery fire from Turkey into Syria continuing into the early hours Thursday.
Syrian authorities are "offering sincerest condolences on behalf of the Syrian government to the family of the deceased and the Turkish people" and are investigating the source of the gunfire, according to the state-run Syrian Arab News Agency (SANA).
"In case of border incidents that occur between any two neighboring countries, countries and governments must act wisely, rationally and responsibly, particularly since there's a special condition on the Syrian-Turkish borders in terms of the presence of undisciplined terrorist groups spread across the borders who have varying agendas and identities," said Syrian Information Minister Omran al-Zoubi.
Opposition groups in Syria said artillery fire from Turkey fell on a government military center near Tal Abyad in northern Syria's Raqqa province. Turkish military reinforcements are deployed near the border, they added.
The artillery shell fired into Turkey came from Tal Abyad, according to Turkey's semiofficial Anadolu news agency..."
The Dry Ice 'Snowflakes' of Mars
|3:26:25 AM, Thursday, September 27, 2012|
"(DiscoveryNews June 19, 2012) Everyone seems to ponder the lyrics of Train's song "Drops of Jupiter," so perhaps it's about time a songwriter includes the "Snowflakes of Mars" in their next ballad. MIT scientists might even be able to add prose to the lyrics by describing their study into the very alien snow that falls from Red Planet skies.
After collecting the vast quantities of data gathered by orbiting Mars spacecraft, the Massachusetts Institute of Technology team has uncovered some rather interesting facts about Martian snow.
But before you start dreaming about snowball fights and reindeer grazing on the slopes of Olympus Mons, think again -- this snow is like nothing we can ever experience on Earth.
For starters, as the majority of the Mars atmosphere is composed of carbon dioxide, the snowflakes are made from CO2 ice -- basically tiny particles of 'dry ice.' Also, the snowflakes are very small -- approximately the size of a red blood cell. "These are very fine particles, not big flakes,” said MIT assistant professor Kerri Cahoy in a press release. If you saw these 'snowflakes' fall, "you would probably see it as a fog, because they're so small," she added.
Using data from NASA's Mars Global Surveyor (MGS) and Mars Reconnaissance Orbiter (MRO), the team also found that the Martian snow buildup in the south arctic regions is 50 percent larger than the snowfall over north arctic regions. There are also seasonal variations -- during the winter, the CO2 snow clouds spread to very low latitudes, about half-way to the Martian equatorial regions (much like on Earth).
But how did the team manage to measure the quantity of snow over the Martian arctic regions in the first place? The researchers made an estimate based on seasonal gravitational variations as detected by satellites in orbit. The tiny fluctuations in Mars' gravitational field over the course of a year corresponded to the buildup of snow.
But they didn't stop there. With a good understanding of the atmospheric conditions and the mass of snowfall, graduate student Renyu Hu (and lead author of the paper published in the Journal of Geophysical Research) was able to get a handle of the size of CO2 ice particles locked in the snowfall. In the north, CO2 'snowflakes' measure 8 to 22 microns wide, whereas in the south, the particles measure between 4 to 13 microns wide.
Getting intimate with the characteristics of the CO2 snow is a testament to the detailed measurements that are continuously being made by the armada of satellites that orbit Mars.
"It’s neat to think that we've had spacecraft on or around Mars for over 10 years, and we have all these great datasets," Cahoy says. "If you put different pieces of them together, you can learn something new just from the data."
Although understanding snowfall and snow cover reveals some wonderful science, this work will also help us understand the dust that is blown around the planet. For the CO2 ice crystals to form in the first place, they need something to condense around -- such as dust particles.
"What kinds of dust do you need to have this kind of condensation?" Hu asks. "Do you need tiny dust particles? Do you need a water coating around that dust to facilitate cloud formation?"
For me, only one more question remains: When will human eyes witness the first flurry of Martian 'snowflakes' as winter sets in during a manned expedition to the Red Planet?"
Conflict and 'boom-bust' explain humans' rapid evolution
|3:19:23 AM, Thursday, September 27, 2012|
"(BBC Sept. 14, 2012) What explains the extraordinarily fast rate of evolution in the human lineage over the past two million years?
A leading human origins researcher has come up with an idea that involves aggression between groups and the boom-bust cycles that have punctuated our spread into new environments.
Prof Ian Tattersall said there were few examples to rival the accelerated evolution that led to our species.
He was speaking at this year's Calpe conference in Gibraltar.
"However you slice it, evolution within this [human family] has been very rapid indeed," Prof Tattersall, from the American Museum of Natural History (AMNH) in New York, told the conference.
"I think it's fair to say that our species Homo sapiens and its antecedents have come much farther, much faster than any other mammalian group that has been documented in this very tight time-frame."
This phenomenon of accelerated evolution is known as "tachytely".
Among our ancestors, brain size doubled between two million and one million years ago. Then it has almost doubled again between one million years and the present day.
Along with the increase in brain size came a reduction in the size of the teeth and face along with other changes in the skull.
The increase in brain size seems to have coincided with a modern physique characterised by a linear shape, long legs and relatively narrow hips. These features can already be seen in the skeleton of the "Turkana boy" from Kenya, who lived about two million years ago.
This contrasts sharply with the short legs and long arms of the Turkana boy's antecedent "Lucy" (Australopithecus afarensis), who lived in Ethiopia about one million years earlier.
Such fast change is not seen among apes, and while Prof Tattersall acknowledges the importance of the move our ancestors made from a tree-dwelling, to a ground-dwelling existence - something which has not affected our primate cousins - he says it is not enough to explain what is observed.
"Clearly the definitive abandonment of dependence on trees... has to count as one of the most radical shifts in adaptive zone ever made by any vertebrate since the very first tetrapod heaved itself out of water and on to terra firma," he said..."
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Humans Were Already Recycling 13,000 Years Ago, Burnt Artifacts Show
|3:14:42 AM, Thursday, September 27, 2012|
"(ScienceDaily Sep. 20, 2012) — A study at the Universitat Rovira i Virgili and the Catalan Institute of Human Paleoecology and Social Evolution (IPHES) reveals that humans from the Upper Palaeolithic Age recycled their stone artefacts to be put to other uses. The study is based on burnt artefacts found in the Molí del Salt site in Tarragona, Spain.
The recycling of stone tools during Prehistoric times has hardly been dealt with due to the difficulties in verifying such practices in archaeological records. Nonetheless, it is possible to find some evidence, as demonstrated in a study published in the ‘Journal of Archaeological Science’.
“In order to identify the recycling, it is necessary to differentiate the two stages of the manipulation sequence of an object: the moment before it is altered and the moment after. The two are separated by an interval in which the artefact has undergone some form of alteration. This is the first time a systematic study of this type has been performed,” as explained to SINC by Manuel Vaquero, researcher at the Universitat Rovira i Virgili.
The archaeologists found a high percentage of burnt remains in the Molí del Salt site (Tarragona), which date back to the end of the Upper Palaeolithic Age some 13,000 years ago. The expert ensures that “we chose these burnt artefacts because they can tell us in a very simple way whether they have been modified after being exposed to fire.”
The results indicate that the recycling of tools was normal during the Upper Palaeolithic Age. However, this practice is not documented in the same way as other types of artefacts. The use of recycled tools was more common for domestic activities and seems to be associated with immediate needs.
Recycling domestic tools
Recycling is linked to expedited behaviour, which means simply shaped and quickly available tools as and when the need arises. Tools used for hunting, like projectile points for instance, were almost never made from recycled artefacts. In contrast, double artefacts (those that combine two tools within the same item) were recycled more often.
“This indicates that a large part of these tools were not conceived from the outset as double artefacts but a single tool was made first and a second was added later when the artefact was recycled,” outlines the researcher. The history of the artefacts and the sequence of changes that they have undergone over time are fundamental in understanding their final morphology.
According to Vaquero, “in terms of the objects, this is mostly important from a cultural value point of view, especially in periods like the Upper Palaeolithic Age, in which it is thought that the sharper the object the sharper the mind.”
Sustainable practices with natural resources
Recycling could have been determinant in hunter-gatherer populations during the Palaeolithic Age if we consider the behaviour of current indigenous populations nowadays.
“It bears economic importance too, since it would have increased the availability of lithic resources, especially during times of scarcity. In addition, it is a relevant factor for interpreting sites because they become not just places to live but also places of resource provision,” states the researcher.
Reusing resources meant that these humans did not have to move around to find raw materials to make their tools, a task that could have taken them far away from camp. “They would simply take an artefact abandoned by those groups who previously inhabited the site.”
Vaquero and the team believe that this practice needs to be borne in mind when analysing the site. “Those populating these areas could have moved objects from where they were originally located. They even could have dug up or removed sediments in search of tools,” highlights the researcher."
Using a Laser to 'See' the Smallest World: Powerful Laser Breathes New Life Into an Old Technology for Studying Atomic-Level Structures
|3:09:36 AM, Thursday, September 27, 2012|
"(ScienceDaily Sep. 19, 2012) A multi-university team has employed a high-powered laser based at UC Santa Barbara to dramatically improve one of the tools scientists use to study the world at the atomic level. The team used their amped-up electron paramagnetic resonance (EPR) spectrometer to study the electron spin of free radicals and nitrogen atoms trapped inside a diamond.
The improvement will pull back the veil that shrouds the molecular world, allowing scientists to study tiny molecules at a high resolution.
The team, which includes researchers from UCSB, University of Southern California (USC), and Florida State University, published its findings this week in Nature.
"We developed the world's first free-electron laser-powered EPR spectrometer," said Susumu Takahashi, assistant professor of chemistry at the USC Dornsife College of Letters, Arts and Sciences, and lead author of the Nature paper. "This ultra high-frequency, high-power EPR system gives us extremely good time resolution. For example, it enables us to film biological molecules in motion."
By using a high-powered laser, the researchers were able to significantly enhance EPR spectroscopy, which uses electromagnetic radiation and magnetic fields to excite electrons. These excited electrons emit electromagnetic radiation that reveals details about the structure of the targeted molecules.
EPR spectroscopy has existed for decades. Its limiting factor is the electromagnetic radiation source used to excite the electrons -- it becomes more powerful at high magnetic fields and frequencies, and, when targeted, electrons are excited with pulses of power as opposed to continuous waves.
Until now, scientists performed pulsed EPR spectroscopy with a few tens of GHz of electromagnetic radiation. Using UCSB's free electron laser (FEL), which emits a pulsed beam of electromagnetic radiation, the team was able to use 240 GHz of electromagnetic radiation to power an EPR spectrometer.
"Each electron can be thought of as a tiny magnet that senses the magnetic fields caused by atoms in its nano-neighborhood," said Mark Sherwin, professor of physics and director of the Institute for Terahertz Science and Technology at UCSB. "With FEL-powered EPR, we have shattered the electromagnetic bottleneck that EPR has faced, enabling electrons to report on faster motions occurring over longer distances than ever before. We look forward to breakthrough science that will lay foundations for discoveries like new drugs and more efficient plastic solar cells.""
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