Nature: New evidence of water on Mercury has surfaced, according to three reports published in Science. One team of researchers, using IR laser pulses, has identified bright regions that they believe indicate water ice, inside nine craters near the planet’s north pole; a second team, using thermal modeling based on data collected by the Messenger spacecraft, has located ultracold spots that line up perfectly with those bright regions; and a third team, also using Messenger data, has spotted hydrogen, another indicator of water ice, in the same areas. The researchers suggest that any water on Mercury probably came from comets or asteroids that struck its surface. The reason the water ice ended up in frigid craters at the pole could be that, over time, it migrated there from the blistering hot surface through a process of vaporization and precipitation.
Ars Technica: Adding conductive nanoparticles to elastic materials usually makes them much more brittle. A group of Korean researchers led by Unyong Jeong from Yonsei University and Jongjin Park from the Samsung Advanced Institute of Technology has developed a technique that maintains the original material’s elasticity. The group spun a combination of butadiene and polystyrene into stretchy fibrous mats. They then soaked the mats in a solution of silver ions, which were absorbed into the material. Using a chemical process, they converted the ions into nanoparticles, resulting in a stretchy mat loaded with conductive fibers. A mat 150 µm thick has a conductivity similar to that of thin gold strips used in large-scale devices. When the material is fully stretched, the conductivity drops only 40%. Jeong and Park used the material as an RF antenna, tunable by how much it is stretched, and as electrodes in an LED.
Washington Post: The Grand Canyon is generally believed to be only 6 million years old. A new study using a technique called thermochronology claims the accepted age is off by an order of magnitude. Thermochronology determines the history of rocks based on their phosphate crystals. The crystals, known as apatite, can trap the helium created by the decay of uranium and thorium. If there is helium in the crystal, then the crystals were formed near the surface. By collecting samples from multiple sites and levels, scientists can determine how long ago the crystals in the rocks formed. Rebecca Flowers of the University of Colorado believes that the thermochronology data her team has collected puts the age of the canyon at 70 million years, and that the canyon was cut in multiple stages. The 70-million-year-old western section was carved by a river flowing opposite the direction of the current Colorado River, And the eastern section would have been carved by a second river 55 million years ago. The Colorado joined the two sections 6 million years ago. Flowers’s theory is facing stiff resistance from other geologists who believe that she is misinterpreting the data she has collected and that the evidence for the 6-million-year-old age is overwhelming.
BBC: The melting of Earth’s polar ice sheets has contributed 11 mm, or about one-fifth, of the overall global sea-level rise over the past two decades, according to the most definitive study to date, published online today in Science. The latest finding is the result of the combined efforts of 20 polar research teams, who used improved modeling and data from NASA and European Space Agency satellites. Because of the remoteness and sheer size of the ice sheets, accurate measurements have been a challenge. The satellites have to distinguish snow from ice, and scientists have to account for the “post-glacial rebound,” or the amount the land rises when the ice melts. By pooling all the researchers’ data, the most recent estimate is “two to three times more reliable than the last one,” according to Andrew Shepherd, a professor at the University of Leeds in the UK and lead author of the study. The next big challenge, say the researchers, is to predict what will happen over the next century.
BBC: The UK’s Reaction Engines Ltd (REL) has run successful tests on key parts of its experimental Synergistic Air-Breathing Rocket Engine (SABRE). SABRE is designed as the engine for Skylon, a horizontal take-off and landing spacecraft. At low altitudes, the engine will operate like a jet, taking in oxygen as fuel from the air. Thus Skylon can launch with much less fuel onboard than traditional spacecraft. During the tests, REL demonstrated an innovative system for rapidly cooling the intake air, which will let the engine operate in air-breathing mode for as long as necessary. The cooling system uses an array of small pipes, through which helium passes. The helium extracts the heat from the air and drops the air temperature to -140 °C in 1/100th of a second. The flowing helium also prevents the buildup of ice on the surface of the pipes, which would reduce the effectiveness of the cooling. The European Space Agency served as an independent observer and confirmed the success of the testing. REL is primarily privately funded and will need to raise £250 million ($400 million) for the next stage of development of SABRE, a version of the engine which will show the viability of the engine in both air-breathing and traditional rocket modes.
MIT News: Collisions between protons and lead ions at CERN’s Large Hadron Collider may have produced a form of matter called a color-glass condensate, which is a liquid-like wave of gluon plasma. In 2 million collisions seen by the LHC’s Compact Muon Solenoid (CMS), some of the resulting particles exhibited behavior that suggested they were entangled. A normal particle collision results in an explosion of particles. But in the lead–proton collisions, some pairs of exploded particles followed matching paths, meaning each particle communicated its direction to the other via entanglement. Gunther Roland of MIT, who led the group analyzing the CMS data, had seen similar shared-path behavior in proton–proton collisions and the collisions of nuclei of heavy elements such as lead and gold. Heavy nuclei collisions produce a quark–gluon plasma, and proton–proton collisions are believed to create a color-glass condensate. Both plasmas sweep up the entangled particles and push them down identical paths. Roland said that the color-glass condensate had not been expected in the lead–proton collisions, which were being done to establish a point of reference for lead–lead collisions. Roland’s group plans additional collisions to try to determine if the color-glass condensate is the cause of the entangled behavior.
Ars Technica: Until now, astronomers had observed that most massive galaxies have supermassive black holes at their centers. However, recent observations of NGC 1277, a relatively small lenticular galaxy 220 million light-years away, indicate that it harbors one of the most massive black holes ever detected. Remco van den Bosch of the Max Planck Institute for Astronomy in Heidelberg, Germany, and colleagues studied high-resolution images captured by the Hobby-Eberly Telescope in Texas. Their results appear online in Nature. According to their measurements, NGC 1277’s central black hole has a mass between 14 billion and 20 billion times that of the Sun. Because five other compact galaxies with properties similar to those of NGC1277 have been observed, the researchers are working to determine whether they, too, have supermassive black holes at their centers.
New York Times: The United Nations Framework Convention on Climate Change is holding its annual meeting this week and next in Doha, Qatar. The current meeting so far promises to be much lower in intensity than the previous three, which were held in Durban, South Africa, in 2011; Cancún, Mexico, in 2010; and Copenhagen in 2009. One of the main topics of discussion will be a global climate change treaty, the details of which the delegates pledged last year to work out by 2015. A number of issues still need to be resolved, including how to verify compliance and how to guarantee equity between rich and poor nations. Because the US is one of the world’s biggest greenhouse gas emitters—along with China—it is expected to play a huge role in the success or failure of the convention to reach an agreement.
Science: A French law passed in March designed to increase job security may have exactly the opposite effect. Researchers across France have been writing letters, signing petitions, and staging street protests over a new requirement that employers must offer a permanent position to employees working on short-term contracts (CDDs) for more than six years. Although the law may work well in certain areas of the public sector, France’s science funding system does not allocate its research institutions sufficient funds to offer their CDD employees permanent jobs. In response, some science organizations, including CNRS—France’s largest—are trying to limit CDDs to three years. Critics say the new law will hurt young researchers the most, by causing them to lose their jobs early on and not allowing them to gain the necessary job experience to seek longer-term positions. France’s higher education and research ministry is working to give CDD employees hiring preference for civil service jobs, and the protesters are pressuring the government to increase the total number of civil service positions.
New Scientist: The original discovery of DNA’s double helix relied on mathematically deducing what structure had created the diffraction pattern revealed by x-ray crystallography. Now scientists have directly imaged the structure using an electron microscope. A team led by Enzo di Fabrizio of the University of Genoa in Italy stretched “cords” of DNA molecules between nanoscopic silicon pillars and took high-resolution images with electron beams. Because the electron beams are too energetic to interact with a single DNA molecule without breaking it, the cords were composed of multiple strands of DNA wrapped around each other. The team hopes to soon be able to use lower-energy electrons to image individual DNA molecules. The new imaging technique may allow researchers to observe how DNA and other molecules interact.