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Updated: 7 hours 46 min ago

Light pollution is drowning out the stars

13 June 2016
The Atlantic: As the world population grows, so, too, does the amount of artificial light from street lamps and other types of outside lighting. As a result, some 99% of North Americans and Europeans now experience a perpetual glow of artificial light at night, and about one-third of all people on Earth can no longer see the Milky Way. Those findings are based on a new dark-sky atlas created from sky-glow satellite data. Researchers say part of the problem is the increasing use of cool-white LEDs, which, because they use less energy and shine more brightly, are replacing the older sodium and metal halide street lamps. One solution is to switch to warm-light LEDs, which are not as bright. Also, downward-directed lamps with better shielding would help minimize the spread of light. Not only should the night sky be protected because it is a valuable natural resource, the researchers say, but some animals depend on moonlight and starlight to navigate and perform other activities.

Four superheavy elements are nameless no more

10 June 2016
The new names commemorate places that fostered creation of the elements and honor a pioneering scientist.

Greenland's record summer melt may be linked to shifting jet stream

10 June 2016
Washington Post: In the summer of 2015, Greenland experienced more melting than usual in its colder, northern regions than in its warmer south. Marco Tedesco of Columbia University and his colleagues have now determined that the unusual melting was caused by an atmospheric phenomenon called a “cutoff high.” That’s when a region of high atmospheric pressure “detaches from the jet stream” and lingers over an area on the ground. In this case it brought a string of sunny days and unusual warmth to the north and blew cold air to the south. The new research also appears to affirm the theory that the jet stream is becoming more distorted. How much climate change may be influencing the jet stream and how it all ties in with melting Arctic sea ice remains to be determined.

Researchers entangle record number of ions in quantum trap

10 June 2016
New Scientist: To study strongly interacting quantum systems, researchers have been trying to assemble larger numbers of entangled particles. Now Justin Bohnet of NIST and his colleagues have set a new record by trapping 219 beryllium ions and entangling their quantum properties. The researchers used the electric and magnetic fields of a Penning trap to grab multiple ions, which then assembled themselves into a two-dimensional crystal array. One pair of lasers was used to cool the array to near absolute zero, while another altered the spins of the ions’ outermost electrons and caused the ions to become entangled. Such systems of entangled ions could be used to study high-temperature superconducting materials and to improve quantum computers.

CarbFix project converts excess atmospheric CO<sub>2</sub> into rock

10 June 2016
Economist: As global warming increases, researchers have been seeking ways to deal with the ever-increasing amounts of greenhouse gases being pumped into the atmosphere. One method proposed by Juerg Matter of Southampton University in the UK and his colleagues is to turn excess carbon dioxide into rock. Their project, called CarbFix, has successfully sequestered the CO2 from the emissions of a geothermal power station in Iceland. About 175 metric tons of the gas was mixed with a radioactive tracker chemical, dissolved in water, and then pumped into a layer of basalt a half kilometer belowground. In less than two years, 95% of the CO2 had been mineralized. Now the CarbFix process is being tested on a larger scale by burying nearly 10 000 metric tons of CO2 as well as 7300 metric tons of hydrogen sulfide, a noxious pollutant also found in exhaust gas.

George Rathjens

10 June 2016

UK insurance company now covers driverless cars

9 June 2016
IEEE Spectrum: Adrian Flux Insurance Services in the UK has developed a reputation for taking on vehicles that are hard to insure elsewhere. The company was started in 1973 by kit car enthusiast Adrian Flux, who had trouble finding insurance for himself. Over the years it has insured hot rods, classic cars, imports, and other types of specialist vehicles. With the growing number of driverless features such as automatic braking and parking being added to today's cars, the company has found a new market for its services. The policy will cover not only user errors, such as failing to update the car’s software, but also some issues that are beyond the driver's control, such as software problems, satellite service outages, and vandalism by hackers. Although the territory is for the most part uncharted, autonomous vehicles are expected to be involved in fewer accidents and suffer less damage than traditional cars.

Proposed names for four new elements await public review

9 June 2016
New Scientist: In December four new elements were added to the periodic table. Officially recognized by both the International Union of Pure and Applied Chemistry and the International Union of Pure and Applied Physics, elements 113, 115, 117, and 118 were assigned placeholder names and symbols until official names could be proposed and approved. The Japanese researchers who discovered element 113 have proposed the name nihonium, after Nihon, which means Japan. The other three elements were discovered by collaborating teams in Russia and the US. The teams have proposed for elements 115, 117, and 118, respectively, the names moscovium, after Moscow; tennessine, after Tennessee; and oganesson, after Yuri Oganessian, a Russian physicist who helped discover element 114 in 1999. The names are expected to become official following a five-month public review.

Google makes advance in universal quantum computing

9 June 2016
Nature: Researchers at Google have developed a prototype quantum computer that improves on earlier designs by combining analog and digital approaches. It is based on adiabatic quantum computing (AQC), in which a group of qubits is encoded with a computational problem and then subjected to gradually changing external conditions. The system arrives at a solution by adapting and adjusting its collective quantum state. Although any problem can be encoded in such an AQC system, errors are rife due to random noise. To correct that problem, the researchers have added digitized quantum computing to take advantage of digital circuits’ ability to systematically correct errors. Google's prototype device consists of a superconducting circuit of nine aluminum qubits deposited on a sapphire surface and cooled to 0.02 K. Although the device comprises just a few qubits, a scaled-up version could be used to solve computational problems too complex for classical computers, such as simulating molecules and materials at the quantum level.

This phase-transforming metal never gets old

9 June 2016
New x-ray diffraction experiments help explain the alloy’s unusual durability.

Sharing solar power in US West faces obstacles

8 June 2016
NPR: California has become a national leader in the generation of green energy due to its numerous solar farms. Nevertheless, the state must continue to maintain its natural gas plants to ensure that all its residents have sufficient power on cloudy days. As a result, much of the solar electricity generated is going to waste because the farms must be shut down periodically to avoid overloading the grid with excess power. One proposed solution has been to share the excess power with neighboring states, but such a proposal has been met with opposition. Many of California’s neighbors, such as Oregon, Utah, and Wyoming, depend on coal for much of their electricity. Accepting solar-generated electricity from California could threaten one of their major industries. As for California, sharing solar power with its coal-dependent neighbors could affect its position as a leader in green energy. But economics may eventually prevail: According to a study by Pacificorp, which services several Western states, its customers could save $2 billion over 20 years by sharing California’s electricity.

Artificial leaf uses bacteria to generate liquid fuel

8 June 2016
Los Angeles Times: Over the past several years, researchers led by Daniel Nocera of Harvard University have been working on a device that uses sunlight to split water and create fuel. Called the artificial leaf, it consists of a semiconductor wafer coated in a catalyst. When dropped in water and exposed to sunlight, the leaf causes the water molecules to split, creating hydrogen gas. Recently the researchers introduced a new element, bacteria, which draw carbon dioxide from the air and combine it with the hydrogen to generate biomass. Not only does the artificial photosynthetic process create green energy, but it could also help reduce atmospheric carbon dioxide. The researchers say they are next going to use the artificial leaf to try to convert atmospheric nitrogen into fertilizers.

US Congress pushes NASA to reconsider Moon mission

8 June 2016
Ars Technica: As the end of President Obama’s term draws near, the US Congress is working to encourage NASA to forgo its proposed 2025 asteroid visit and instead reconsider a human mission to the Moon. A bipartisan effort in the House of Representatives is being led by Mike Honda (D-CA) and Jim Bridenstine (R-OK), who are promoting a lunar mission as the best proving ground for a mid 2030s Mars mission. Because of the ever-increasing costs of the asteroid project, it has had to be scaled back several times—from sending astronauts to visit an asteroid in deep space, to bringing an asteroid to a location near the Moon, and finally to just grabbing a small boulder from an asteroid’s surface and bringing that back near the Moon. Legislators feel that a lunar mission is not only more attainable but also necessary to remain competitive with other nations, such as Russia and China, and to provide opportunities for the nascent commercial space industry.

Marshall Islands radioactivity levels have dropped

7 June 2016
Science: Because the US conducted extensive nuclear testing there during the 1940s and 1950s, several islands in the Marshall Island chain became highly contaminated and had to be abandoned. Almost 60 years later, researchers have determined that the gamma radiation levels of five of the islands have dropped to less than 40 millirem per year, well below the 100 millirem per year threshold deemed safe for human habitation. Bikini Island, however, still registers 184 millirem per year. Because people can absorb radiation in other ways, such as by consuming contaminated food, more tests will be needed before anyone will be allowed to occupy the islands.

Ocean instrument network comes on line

7 June 2016
Nature: As of 6 June, the seven underwater instrument arrays that make up the Ocean Observatories Initiative (OOI) are up and running. Nearly 10 years in the making, the NSF-supported project aims to stream information gathered by more than 900 sensors on the ocean’s physical, chemical, geological, and biological properties and processes. About 85% of OOI data are available in real time on the project’s website, and more will be added each week. The array off the US East Coast has already measured the air–sea fluxes caused by a hurricane, and the West Coast array has studied a warm patch of water influencing weather patterns in California. Proposed budget cuts, however, threaten to affect the servicing of the instrument arrays, which have yet to be properly tested. At least a year’s worth of data will be needed to assess their worth and usefulness to the scientific community.

US poised to approve first private Moon launch

7 June 2016
Wall Street Journal: Until now only national governments have undertaken space missions beyond Earth orbit. That may soon change as Moon Express, a private US space company, readies its MX-1 commercial lunar lander for a 2017 launch. Moon Express is competing for the Google Lunar X prize, to be awarded to the first company to land a privately funded robotic spacecraft on the Moon. US launches are regulated by the Federal Aviation Administration, which is currently reviewing the process for granting commercial operations permission to conduct space missions beyond Earth’s gravitational pull. Such permission must take into account international treaty obligations and concerns over public safety, national security, and foreign policy. The FAA is expected to reach a decision within the next few weeks.

Vacuum-tube technology is revisited to further shrink electronic circuits

7 June 2016
New York Times: More than a century ago, the invention of the vacuum tube kicked off an electronics revolution. However, the tubes were big and bulky, and by the 1970s, they were replaced by the transistor. One problem with the transistor design is that the smaller the transistor gets, the more it leaks electrons because of a phenomenon called quantum tunneling. Now Axel Scherer of Caltech and his coworkers are developing a new take on the old vacuum-tube technology. Scherer's team uses the quantum tunneling effect as the switch to control the flow of electrons in tiny metal vacuum tubes. The new tubes use less power and work faster than current transistor-based chips, so they could have many applications, such as in space and aviation.

The freest of free falls

7 June 2016
In a space-based gravitational-wave detector, gravity should be the only force accelerating an interferometer.

New satellite imagery detects previously hidden magma chambers

6 June 2016
Nature: Usually with volcanoes, the surface subsides around them because of the draining of magma-filled chambers in the ground beneath. But magma may pool in chambers far from any active volcano, according to a new study. Using satellite radar data and geodetic surveys, Ian Hamling of GNS Science in New Zealand and his colleagues were able to distinguish an unexpected rise in the ground in the Taupo Volcanic Zone of New Zealand’s North Island. Moreover, the ground appears to have been rising for more than a half century and at an ever-increasing rate—from about 5 mm/year in the 1950s to some 12 mm/year by the mid 2000s. However, the researchers say the magma increase does not necessarily mean an eruption is imminent. Moreover, similar processes have probably been going on all over the world; it is only now that instruments have been developed to detect them.