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Ice Age Art: Arrival of the Modern Mind – in pictures

Ice Age Art: Arrival of the Modern Mind – in pictures | Fragments of Science | Scoop.it
Images from the British Museum's forthcoming exhibition of ice age artefacts made between 13,000 and 42,000 years ago
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Fragments of Science
The history, present and future and nature of science and their relationship
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Optical forces used to make rewritable 3-D holographic materials

Optical forces used to make rewritable 3-D holographic materials | Fragments of Science | Scoop.it
Researchers have used the pressure of light—also called optical forces or sometimes "tractor beams"—to create a new type of rewritable, dynamic 3D holographic material. Unlike other 3D holographic materials, the new material can be rapidly written and erased many times, and can also store information without using any external energy. The new material has potential applications in 3D holographic displays, large-scale volumetric data storage devices, biosensors, tunable lasers, optical lenses, and metamaterials.

The research was conducted by a multidisciplinary team led by Yunuen Montelongo at Imperial College London and Ali K. Yetisen at Harvard University and MIT. In recent papers published in Nature Communications and Applied Physics Letters, the researchers demonstrated the reversible optical manipulation of nanostructured materials, which they used to fabricate active 3D holograms, lenses, and memory devices.

The key to creating the 3D holographic material with these advantages was to use optical forces to reversibly modify the material's properties. The optical forces are produced by the interference of two or more laser beams, which creates an optical pressure capable of moving nanoscale structures.
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Giant dinosaur footprint discovered in Mongolia desert

Giant dinosaur footprint discovered in Mongolia desert | Fragments of Science | Scoop.it
One of the biggest dinosaur footprints ever recorded has been unearthed in the Gobi Desert, researchers said Friday, offering a fresh clue about the giant creatures that roamed the earth millions of years ago.

A joint Mongolian-Japanese expedition found the giant print, which measures 106 centimetres (42 inches) long and 77 centimetres wide.

One of several footprints discovered in the vast Mongolian desert, the huge fossil was discovered last month in a geologic layer formed between 70 million and 90 million years ago, researchers said.

It was naturally cast, as sand flowed into dents that had been left by the creature stomping on the once muddy ground.

The footprint is believed to have belonged to Titanosaur, a long-necked dinosaur, and could have been more than 30 metres long and 20 metres tall, according researchers.

"This is a very rare discovery as it's a well-preserved fossil footprint that is more than a metre long with imprints of its claws," said a statement issued by Okayama University of Science.
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'Pandora's Cluster' seen by Spitzer

'Pandora's Cluster' seen by Spitzer | Fragments of Science | Scoop.it
This image of galaxy cluster Abell 2744, also called Pandora's Cluster, was taken by the Spitzer Space Telescope. The gravity of this galaxy cluster is strong enough that it acts as a lens to magnify images of more distant background galaxies. This technique is called gravitational lensing.

The fuzzy blobs in this Spitzer image are the massive galaxies at the core of this cluster, but astronomers will be poring over the images in search of the faint streaks of light created where the cluster magnifies a distant background galaxy.

The cluster is also being studied by NASA's Hubble Space Telescope and Chandra X-Ray Observatory in a collaboration called the Frontier Fields project. Hubble's image of Abell 2744 can be seen here.

In this image, light from Spitzer's infrared channels is colored blue at 3.6 microns and green at 4.5 microns.
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Rosetta: The beginning of the end

Rosetta: The beginning of the end | Fragments of Science | Scoop.it
Europe was poised to send its Rosetta spacecraft on Thursday toward a crash landing on the comet it has stalked for the last two years, joining robot lander Philae on the icy dustball's surface for eternity.

The mission will conclude with a last-gasp spurt of science-gathering as Rosetta quits the orbit of comet 67P/Churyumov-Gerasimenko at about 2050 GMT to start a 14-hour, 19-kilometre (12-mile) descent.

This will all happen more than 700 million kilometres from Earth, with the comet and Rosetta zipping through space at a speed of over 14 kilometres (nine miles) per second.

"Rosetta will collect science data until the very end of its descent," said the European Space Agency's Rosetta blog.

"The opportunity to study a comet at such close proximity makes the descent phase one of the most exciting of the entire mission."

A "controlled impact" is scheduled for about 1040 GMT on Friday, with confirmation of the end of the mission expected some 40 minutes later, which is how long it takes for a signal from Rosetta to reach Earth.

After 12 years in space, Rosetta's signal will simply vanish from computer screens at mission control in Darmstadt, Germany.

The first-ever mission to orbit and land on a comet was approved in 1993 to explore the origins and evolution of our Solar System—of which comets are thought to contain prehistoric elements preserved in a dark space deep freeze.
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Gaia: Here Comes the Sun

"What would it look like to return home from outside our galaxy? Although designed to answer greater questions, recent data from ESA's robotic Gaia mission is helping to provide a uniquely modern perspective on humanity's place in the universe.


Gaia orbits the Sun near the Earth and resolves star's positions so precisely that it can determine a slight shift from its changing vantage point over the course of a year, a shift that is proportionately smaller for more distant stars -- and so determines distance. In the first sequence of the video, an illustration of the Milky Way is shown that soon resolves into a three-dimensional visualization of Gaia star data.


A few notable stars are labelled with their common names, while others stars are labelled with numbers from Gaia's catalog.


Eventually the viewer arrives at our home star Sol (the Sun), then resolving the reflective glow of its third planet: Earth. The featured video is based on just over 600,000 stars, but Gaia is on track to measure the parallax distances to over one billion stars over its planned five year mission."


Credit: Galaxy illustration: Nick Risinger; Star Data: Gaia, ESA, Toni Sagristà (U. Heidelberg)


Details: http://apod.nasa.gov/apod/ap160926.html

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Ambient air pollution: A global assessment of exposure and burden of disease

Ambient air pollution: A global assessment of exposure and burden of disease | Fragments of Science | Scoop.it
This report presents a summary of methods
and results of the latest World Health Organization
(WHO) global assessment of ambient
air pollution exposure and the resulting burden
of disease.
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New low-mass objects could help refine planetary evolution

New low-mass objects could help refine planetary evolution | Fragments of Science | Scoop.it
When a star is young, it is often still surrounded by a primordial rotating disk of gas and dust, from which planets can form.
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Plastic flower blooms thanks to its own internal molecular clock

Plastic flower blooms thanks to its own internal molecular clock | Fragments of Science | Scoop.it
Shape-shifting putty that can morph at a given time without an external trigger may be useful for creating medical implants that transform inside the body
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Human Level Artificial Intelligence 2016: Artificial General Intelligence and then some (Part 2)

Human Level Artificial Intelligence 2016: Artificial General Intelligence and then some (Part 2) | Fragments of Science | Scoop.it
In its inception, the field of Artificial Intelligence (AI) sought to create computers with general intelligence analogous to our own. This proved to be too challenging and elusive, thereby leading AI research to focus more narrowly on the development of intelligent systems capable of performing only problem- and domain-specific tasks, thereby giving rise to narrow, or weak, Artificial Intelligence. That said, interest in creating systems possessing human-like (and potentially beyond) general, or strong, Artificial Intelligence has reemerged and been termed Artificial General Intelligence (AGI). However, since the term Artificial Intelligence is often mistakenly used to describe both AI and AGI, confusion among the general population often ensues.

Read Part 1: Human Level Artificial Intelligence 2016: Artificial General Intelligence and then some: https://techxplore.com/news/2016-09-human-artificial-intelligence.html
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Study shows a baby makes copies of maternal immune cells it acquires through mother's milk

Study shows a baby makes copies of maternal immune cells it acquires through mother's milk | Fragments of Science | Scoop.it
Scientists have long understood that mother's milk provides immune protection against some infectious agents through the transfer of antibodies, a process referred to as "passive immunity." A research team at the University of California, Riverside now shows that mother's milk also contributes to the development of the baby's own immune system by a process the team calls "maternal educational immunity."

Specific maternal immune cells in the milk cross the wall of the baby's intestine to enter an immune organ called the thymus. Once there, they "educate" developing cells to attack the same infectious organisms to which the mother has been exposed.
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Shape-programmable miniscule robots

Shape-programmable miniscule robots | Fragments of Science | Scoop.it
One day, microrobots may be able to swim through the human body like sperm or paramecia to carry out medical functions in specific locations. Researchers from the Max Planck Institute for Intelligent Systems in Stuttgart have developed functional elastomers, which can be activated by magnetic fields to imitate the swimming gaits of natural flagella, cilia and jellyfish. Using a specially developed computer algorithm, the researchers can now automatically generate the optimal magnetic conditions for each gait for the first time. According to the Stuttgart-based scientists, other applications for this shape-programming technology include numerous other micro-scale engineering applications, in which chemical and physical processes are implemented on a miniscule scale.

A sperm is equipped with a flagellum (tail-like extension), which can beat constantly back and forth to propel the sperm towards an egg. Researchers from the Max Planck Institute for Intelligent Systems in Stuttgart have now enabled an extremely thin strip of silicone rubber, which is just a few millimetres in length, to achieve a very similar swimming pattern. To do this, they embedded magnetizable neodymium-iron-boron particles into an elastic silicone rubber and subsequently magnetized this elastomer in a controlled way. Once the elastomer is placed under a specified magnetic field, the scientists were then able to control the elastomer's shape, making it beat back and forth in a wave-like fashion.

The scientists also succeeded in imitating the complex rowing movement of a cilium in a very similar way. Cilia are extremely fine hairs found on the surface of paramecia – they propel the organisms forward by using highly complex rowing strokes. The researchers also constructed an artificial jellyfish that has two soft tentacles, which have been programmed to carry out rowing-like swimming movements.

The crucial factor behind all of these movement processes is that different areas of the elastomer can react differently to an external magnetic field: some zones have to be attracted and others repelled. Otherwise, the elastomer would not be able to reshape into a wave or begin to roll up at its ends.
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Scientists stop light in a cloud of atoms

Scientists stop light in a cloud of atoms | Fragments of Science | Scoop.it
They may not be wearing the robes of Jedi warriors, but Australian scientists have created their own version of a Star Wars scene by stopping light in a cloud of very cold atoms, a development that provides a essential building block for quantum computing.
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Acceleration relation found among spiral and irregular galaxies challenges current understanding of dark matter

Acceleration relation found among spiral and irregular galaxies challenges current understanding of dark matter | Fragments of Science | Scoop.it
In the late 1970s, astronomers Vera Rubin and Albert Bosma independently found that spiral galaxies rotate at a nearly constant speed: the velocity of stars and gas inside a galaxy does not decrease with radius, as one would expect from Newton's laws and the distribution of visible matter, but remains approximately constant. Such 'flat rotation curves' are generally attributed to invisible, dark matter surrounding galaxies and providing additional gravitational attraction.

Now a team led by Case Western Reserve University researchers has found a significant new relationship in spiral and irregular galaxies: the acceleration observed in rotation curves tightly correlates with the gravitational acceleration expected from the visible mass only.

"If you measure the distribution of star light, you know the rotation curve, and vice versa," said Stacy McGaugh, chair of the Department of Astronomy at Case Western Reserve and lead author of the research.

The finding is consistent among 153 spiral and irregular galaxies, ranging from giant to dwarf, those with massive central bulges or none at all. It is also consistent among those galaxies comprised of mostly stars or mostly gas.

In a paper accepted for publication by the journal Physical Review Letters and posted on the preprint website arXiv, McGaugh and co-authors Federico Lelli, an astronomy postdoctoral scholar at Case Western Reserve, and James M. Schombert, astronomy professor at the University of Oregon, argue that the relation they've found is tantamount to a new natural law.

An astrophysicist who reviewed the study said the findings may lead to a new understanding of internal dynamics of galaxies.

"Galaxy rotation curves have traditionally been explained via an ad hoc hypothesis: that galaxies are surrounded by dark matter," said David Merritt, professor of physics and astronomy at the Rochester Institute of Technology, who was not involved in the research. "The relation discovered by McGaugh et al. is a serious, and possibly fatal, challenge to this hypothesis, since it shows that rotation curves are precisely determined by the distribution of the normal matter alone. Nothing in the standard cosmological model predicts this, and it is almost impossible to imagine how that model could be modified to explain it, without discarding the dark matter hypothesis completely."

McGaugh and Schombert have been working on this research for a decade and with Lelli the last three years. Near-infrared images collected by NASA's Spitzer Space Telescope during the last five years allowed them to establish the relation and that it persists for all 153 galaxies.
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Curiosity finds evidence of Mars crust contributing to atmosphere

Curiosity finds evidence of Mars crust contributing to atmosphere | Fragments of Science | Scoop.it
NASA's Curiosity rover has found evidence that chemistry in the surface material on Mars contributed dynamically to the makeup of its atmosphere over time. It's another clue that the history of the Red Planet's atmosphere is more complex and interesting than a simple legacy of loss.

The findings come from the rover's Sample Analysis at Mars, or SAM, instrument suite, which studied the gases xenon and krypton in Mars' atmosphere. The two gases can be used as tracers to help scientists investigate the evolution and erosion of the Martian atmosphere. A lot of information about xenon and krypton in Mars' atmosphere came from analyses of Martian meteorites and measurements made by the Viking mission.

"What we found is that earlier studies of xenon and krypton only told part of the story," said Pamela Conrad, lead author of the report and SAM's deputy principal investigator at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "SAM is now giving us the first complete in situ benchmark against which to compare meteorite measurements."

Of particular interest to scientists are the ratios of certain isotopes - or chemical variants - of xenon and krypton. The SAM team ran a series of first-of-a-kind experiments to measure all the isotopes of xenon and krypton in the Martian atmosphere. The experiments are described in a paper published in Earth and Planetary Science Letters.

The team's method is called static mass spectrometry, and it's good for detecting gases or isotopes that are present only in trace amounts. Although static mass spectrometry isn't a new technique, its use on the surface of another planet is something only SAM has done.
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Viking arrowheads emerge from melting Norwegian glaciers

Viking arrowheads emerge from melting Norwegian glaciers | Fragments of Science | Scoop.it
Julian Martinsen bends down and places a tape measure next to a small treasure located between two large rocks. He is the curator and archaeologist in Oppland County and has been  tasked with picking up and packing the artefacts that the team of archaeologists find.
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Iron nanoparticles make immune cells attack cancer

Iron nanoparticles make immune cells attack cancer | Fragments of Science | Scoop.it
Stanford researchers accidentally discovered that iron nanoparticles invented for anemia treatment have another use: triggering the immune system's ability to destroy tumor cells.

Iron nanoparticles can activate the immune system to attack cancer cells, according to a study led by researchers at the Stanford University School of Medicine.

The nanoparticles, which are commercially available as the injectable iron supplement ferumoxytol, are approved by the Food and Drug Administration to treat iron deficiency anemia.

The mouse study found that ferumoxytol prompts immune cells called tumor-associated macrophages to destroy cancer cells, suggesting that the nanoparticles could complement existing cancer treatments. The discovery, described in a paper published online Sept. 26 in Nature Nanotechnology, was made by accident while testing whether the nanoparticles could serve as Trojan horses by sneaking chemotherapy into tumors in mice.

"It was really surprising to us that the nanoparticles activated macrophages so that they started to attack cancer cells in mice," said Heike Daldrup-Link, MD, who is the study's senior author and an associate professor of radiology at the School of Medicine. "We think this concept should hold in human patients, too."

Daldrup-Link's team conducted an experiment that used three groups of mice: an experimental group that got nanoparticles loaded with chemo, a control group that got nanoparticles without chemo and a control group that got neither. The researchers made the unexpected observation that the growth of the tumors in control animals that got nanoparticles only was suppressed compared with the other controls.
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Scientists find evidence for alternate theory of how life arose

Scientists find evidence for alternate theory of how life arose | Fragments of Science | Scoop.it
A new study led by scientists at The Scripps Research Institute (TSRI) offers a twist on a popular theory for how life on Earth began about four billion years ago.

The study questions the "RNA world" hypothesis, a theory for how RNA molecules evolved to create proteins and DNA. Instead, the new research offers evidence for a world where RNA and DNA evolved simultaneously.

"Even if you believe in a RNA-only world, you have to believe in something that existed with RNA to help it move forward," said Ramanarayanan Krishnamurthy, associate professor of chemistry at TSRI and senior author of the new study. "Why not think of RNA and DNA rising together, rather than trying to convert RNA to DNA by means of some fantastic chemistry at a prebiotic stage?"

The study was published recently in the journal Angewandte Chemie.
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How our cells use mother's and father's genes

How our cells use mother's and father's genes | Fragments of Science | Scoop.it
Researchers at Karolinska Institutet and Ludwig Institute for Cancer Research have characterized how and to what degree our cells utilize the gene copies inherited from our mother and father differently. At a basic level this helps to explain why identical twins can appear rather different, even though they share identical genetic makeup. With this knowledge we will better understand the variation in outcomes of genetic disorders.

Humans have two copies of all autosomal genes, one inherited from the mother and one from the father, and often the two copies are not perfectly identical due to small differences in their DNA sequence. Therefore, variation in the utilization of the two copies in cells has functional consequences, but the nature and patterns of their gene copy utilization has remained largely unknown. Now, the researchers have provided answers to this longstanding question in molecular genetics. They used allele-sensitive gene expression analyses, so called "single-cell RNA-sequencing", on the newly divided cells to characterize the dynamics of gene copy expression in mouse and human cells in remarkable detail.

"Our experiments allowed us to determine which genes get locked into expressing only one gene copy and which genes that dynamically switches between the two gene copies over time", says Björn Reinius, at the Department of Cell and Molecular Biology one of the lead authors of the study published in the journal Nature Genetics.
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The controversial technique: World’s first baby born with new “3 parent” technique

The controversial technique: World’s first baby born with new “3 parent” technique | Fragments of Science | Scoop.it
A five-month-old boy is the first baby to be born using a new technique that incorporates DNA from three people, New Scientist can reveal. “This is great news and a huge deal,” says Dusko Ilic at King’s College London, who wasn’t involved in the work. “It’s revolutionary.” The controversial technique, which allows parents with rare genetic mutations to have healthy babies, has only been legally approved in the UK. But the birth of the child, whose Jordanian parents were treated by a US-based team in Mexico, should fast-forward progress around the world, say embryologists.
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20 Gifs That Teach You Science Concepts In Seconds

20 Gifs That Teach You Science Concepts In Seconds | Fragments of Science | Scoop.it
There are a number of collections that are like this—collections that aim to demonstrate science concepts in a way that is easily digestible.
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Diagram captures microbes’ influence across species

Diagram captures microbes’ influence across species | Fragments of Science | Scoop.it
A network diagram of animal species shows that many microbes living in humans also make themselves at home in dogs, pigs and cattle.

 

At least 233 species of bacteria, viruses and more live on or inside both humans and dogs. That’s one finding from a study that matched animals with their known microbes and drew connections between species with similar microbial crews. The diagram below, published September 15 in Scientific Data, is a social network of species that resembles a vibrant tangle of yarn.

 

Each dot is an animal species; the creatures are clumped into colored groups such as light blue for fish and yellow for birds. Humans have the largest dot because they host at least 1,600 different microbes. The distance between dots and the lines connecting them indicate that many human microbes also reside in dogs, pigs and cattle.


Domesticated animals live beside humans, so the microbial overlap isn’t surprising, says study coauthor Maya Wardeh, a computational biologist at the University of Liverpool in England. Yet humans share microbes with fish and fall victim to Cryptosporidium fayeri, a diarrhea-inducing parasite that also infects the eastern gray kangaroo.

 

Wardeh and colleagues say that scientists can use the information to study how various diseases originate and jump between species.


Via Dr. Stefan Gruenwald
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Parkinson's disease protection may begin in the gut: Intestinal cells' immune response protects vital neurons

Parkinson's disease protection may begin in the gut: Intestinal cells' immune response protects vital neurons | Fragments of Science | Scoop.it
Researchers at the University of Iowa have found that the gut may be key to preventing Parkinson's disease. Cells located in the intestine spark an immune response that protects nerve cells, or neurons, against damage connected with Parkinson's disease. Acting like detectives, the immune intestinal cells identify damaged machinery within neurons and discard the defective parts. That action ultimately preserves neurons whose impairment or death is known to cause Parkinson's.

"We think somehow the gut is protecting neurons," says Veena Prahlad, assistant professor in biology at the UI and corresponding author on the paper published Aug. 30 in the journal Cell Reports.

Parkinson's disease is a brain disorder that erodes motor control and balance over time. It affects some 500,000 people in the U.S., according to the National Institutes of Health. The disease occurs when neurons—nerve cells—in the brain that control movement become impaired or die. Normally, these neurons produce dopamine, and when they are damaged or killed, the resulting dopamine shortage causes the motor-control problems associated with the disease.

Scientists have previously linked Parkinson's to defects in mitochondria, the energy-producing machinery found in every human cell. Why and how mitochondrial defects effect neurons remain a mystery. Some think the impaired mitochondria starve neurons of energy; others believe they produce a neuron-harming molecule. Whatever the answer, damaged mitochondria have been linked to other nervous disorders as well, including ALS and Alzheimer's, and researchers want to understand why.
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CRISPR toolbox expanded by protein that cuts RNA in two distinct ways

CRISPR toolbox expanded by protein that cuts RNA in two distinct ways | Fragments of Science | Scoop.it
UC Berkeley biochemist Jennifer Doudna, molecular biologist Robert Tijan and a team of researchers have expanded the role of the newly discovered CRISPR protein C2c2 that targets RNA instead of DNA.

C2c2 has been described as an RNA-guided RNA-cutting enzyme; however, a full understanding of how this protein acts to cleave RNA was lacking. In a paper published today in Nature titled "Two distinct RNase activities of CRISPR-C2c2 enable guide-RNA processing and RNA detection," the researchers were able to show that C2c2 has not one, as previously thought, but two distinct RNA cutting activities that in concert can be harnessed for robust RNA detection and degradation.

"This study expands our molecular understanding of C2c2 to guide RNA processing and provides the first application of this novel RNase," said Doudna, who is also a Howard Hughes Medical Institute investigator. "C2c2 is essentially a self-arming sentinel that attacks all RNAs upon detecting its target. This activity can be harnessed as an auto-amplifying detector that may be useful as a low-cost diagnostic."

The two distinct RNA cutting activities each have their own function. The first is responsible for producing guide RNAs that enable C2c2 to find specific target RNA molecules. The second, activated once a complementary RNA target is found, serves as a general RNA cleaver that destroys all RNAs that are present.
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Methane was not the climate savior once imagined for the middle chapter of Earth history

Methane was not the climate savior once imagined for the middle chapter of Earth history | Fragments of Science | Scoop.it
For at least a billion years of the distant past, planet Earth should have been frozen over but wasn't. Scientists thought they knew why, but a new modeling study from the Alternative Earths team of the NASA Astrobiology Institute has fired the lead actor in that long-accepted scenario.

Humans worry about greenhouse gases, but between 1.8 billion and 800 million years ago, microscopic ocean dwellers really needed them. The sun was 10 to 15 percent dimmer than it is today—too weak to warm the planet on its own. Earth required a potent mix of heat-trapping gases to keep the oceans liquid and livable.

For decades, atmospheric scientists cast methane in the leading role. The thinking was that methane, with 34 times the heat-trapping capacity of carbon dioxide, could have reigned supreme for most of the first 3.5 billion years of Earth history, when oxygen was absent initially and little more than a whiff later on. (Nowadays oxygen is one-fifth of the air we breathe, and it destroys methane in a matter of years.)

"A proper accounting of biogeochemical cycles in the oceans reveals that methane has a much more powerful foe than oxygen," said Stephanie Olson, a graduate student at the University of California, Riverside, a member of the Alternative Earths team and lead author of the new study published September 26 in the Proceedings of the National Academy of Sciences. "You can't get significant methane out of the ocean once there is sulfate."
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How light and atoms work together to build a quantum gate.

How light and atoms work together to build a quantum gate. | Fragments of Science | Scoop.it
How light and atoms work together to build a quantum gate. Source: ANU
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