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Updated: 59 min 36 sec ago

Incredible light activity photographed above thunderstorms

26 April 2016
New Scientist: Blue jets, red sprites, and glimpses are the names of some of the bright phenomena that occur above clouds during thunderstorms. During a stay aboard the International Space Station, Danish astronaut Andreas Mogensen captured four videos and 160 photos of the weird activity. Although blue jets and sprites have been observed before, the so-called glimpses, or blue blobs of light, were unexpected. The images were presented at the European Geosciences Union meeting last week in Vienna. Also shown were ground-based images of lightning, such as the impressive view of giant upside-down jets of electrostatic discharge fanning out from a monsoon cloud over India. Although lightning is a common occurrence on Earth, its unpredictability has made it hard to study.

“Pushing the greenies to confront their nuclear contradictions”

25 April 2016
Columnists from dissimilar national newspapers offer unusual analyses of emissions-reduction possibilities.

Iron isotope points to recent nearby supernovae

25 April 2016

Los Angeles Times: For the last 17 years, the Cosmic Ray Isotope Spectrometer (CRIS) on NASA's Advanced Composition Explorer spacecraft has been detecting particles approaching Earth. In that time, it has identified more than 30 000 particles of ordinary iron-56 and just 15 particles of radioactive iron-60. But the radioactive isotopes provided enough information for researchers working with CRIS to determine a source. Heavy elements such as iron are created in supernova explosions, but it takes the shock wave of a second supernova to accelerate the atoms and turn them into cosmic rays. The 2.6-million-year half-life of iron-60 allowed researchers to determine that the supernovae that launched the iron particles toward Earth occurred within 2 million years of each other and were relatively nearby. The finding closely matches a separate study that recently suggested a nearby star went supernova roughly 2.3 million years ago.

Lighter, faster, cheaper detection of radiocarbon

25 April 2016
A compact spectroscopic system can measure radiocarbon dioxide concentrations as low as 5 parts per 1015.

Vast coral reef explored in Brazil

25 April 2016
NPR: The presence of an extensive coral reef at the mouth of South America’s Amazon River has surprised researchers. The reason is the unlikely environment—muddy, freshwater rather than the clear, salty seawater that plays host to most of the world’s reefs. Fabiano Thompson of the Federal University of Rio de Janeiro in Brazil and his colleagues, whose study appears in Science Advances, recently conducted the largest ever survey of the reef. Previous efforts had been hampered by the rough waters and depth of the reef, which can be as much as 100 m. The researchers found that the reef covers some 9500 km2, an area larger than Delaware, and is home to numerous species, including red algae, sponges, corals, and fish. Moreover, many specimens collected have yet to be identified and may represent entirely new species. There may be much more to be discovered: The survey covered just 10% of the system. From what they’ve seen, the researchers say the reef may represent a unique ecosystem. That identification will be important to garner support to protect the area, particularly from the exploratory oil and gas drilling that has already begun nearby.

Presence of manganese oxide on Mars suggests ancient oxygen-rich atmosphere

25 April 2016

New Scientist: Mars's atmosphere is currently 95% carbon dioxide, with only trace amounts of oxygen. Because the planet's red coloring is the result of oxidization of iron on the surface, many scientists believe that the atmosphere used to be more oxygen-rich. However, there was little direct evidence to support the theory. Now NASA's Curiosity rover has identified significant amounts of manganese oxide in rocks in Gale crater. According to Agnès Cousin of the Research Institute in Astrophysics and Planetology in Toulouse, France, the formation of that oxidized manganese would have required much more oxygen than is present in the current atmosphere.

Solar-powered plane on round-the-world flight reaches California

25 April 2016
BBC: On 23 April the experimental solar-powered aircraft Solar Impulse 2 landed at Moffett Airfield in Mountain View, California. It had just completed the ninth leg of its historic trip around the world, during which it took almost three days to fly from Kalaeloa, Hawaii, to the US West Coast. Although Solar Impulse 2 began its journey more than a year ago, taking off in March 2015 from Abu Dhabi in the United Arab Emirates, it was grounded for almost nine months in Hawaii because of a problem with its batteries, which had overheated during the record-setting flight across the Pacific Ocean. The plane’s two pilots, Bertrand Piccard and André Borschberg, take turns flying the single-passenger craft. They hope to reach New York by early June to start preparing for the trans-Atlantic leg and their return to the starting point in Abu Dhabi.

Carbon nanotubes developed as light emitters for optical circuits

22 April 2016
IEEE Spectrum: To advance telecommunications technology, researchers have been working to further miniaturize integrated circuits to pack more on a single chip. One way is to use photons rather than electrons to transmit data. Although no viable integrated optical circuit using photons has yet been achieved, a team at Karlsruhe Institute of Technology in Germany has taken a step in that direction by developing a nanoscale photonic emitter. The researchers used carbon nanotubes (CNTs) to convert electrical signals into optical ones. Through the use of dielectrophoresis, they then integrated the light-emitting CNTs into nanostructured waveguides to direct the light. They next hope to install the new emitter device into larger, more complex structures and eventually build a complete photonic circuit.

University's majority share of patent profits can stifle innovation

22 April 2016
Science: In the US, university researchers who apply for patents share any benefits earned with their home university. Typically the university receives a majority share, often as much as two-thirds the value of the patent. That approach has been touted by experts who claim it nurtures innovation, and they have urged other nations to adopt a similar formula. Now, however, its effectiveness is being called into question. In 2002 Norway ended its long-running practice of “professor’s privilege” in favor of the US-style system granting university researchers just a one-third share. A decade and a half later, Hans Hvide of the University of Bergen in Norway and Benjamin Jones of Northwestern University in Illinois looked at how university commercialization in Norway has been affected. They found that not only did the per capita number of patents drop by 53% and the number of university-backed startup companies by 67%, but overall quality of commercial activity declined, based on the companies’ success and the number of citations earned per patent. They attribute the drop to the uneven division of profits and emphasize the importance of negotiating terms that satisfy all parties.

Andrey Loginov

22 April 2016

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22 April 2016

Solar-powered plane resumes round-the-world flight after months-long delay

22 April 2016
NPR: After being grounded in Hawaii for the past nine months, Solar Impulse 2, an experimental solar-powered aircraft, was finally able to take off and continue on the next leg of its historic trip around the world. Pilots Bertrand Piccard and André Borschberg began their journey in March 2015, when the plane took off from Abu Dhabi in the United Arab Emirates. Because the craft holds just one person, the two pilots take turns flying it. In June 2015, Borschberg broke the record for the longest solo flight without refueling: He flew almost 118 hours straight from Japan to Hawaii. During the flight, however, the plane’s batteries overheated; the repair ended up taking months. Piccard finally resumed the historic trip on 21 April, when, despite gusty winds, he took off for Mountain View, California.

A conversation with incoming NAS president Marcia McNutt

22 April 2016
As president of the National Academy of Sciences, McNutt hopes to help address climate change, food security, water availability, and other national and global challenges.

Gravitational effects on the LHC could be used to measure rain and snowfall

21 April 2016

BBC: Gravitational forces introduce tiny but measurable fluctuations in the length of the Large Hadron Collider's (LHC's) 27 km circumference. The changes can be seen when the particle beams are calibrated to ensure they pass through the center of the ring's vacuum chamber. Any shift in the beams' position can be measured with micrometer accuracy. Those length fluctuations occur both daily and seasonally. The daily fluctuations are caused by normal tidal forces. Now one group of researchers investigating the fluctuations believes that the seasonal changes are caused by water from rain and snow, which accumulates during the winter and evaporates during the summer. Rolf Hut of Delft University of Technology, the Netherlands, and his colleagues found a correlation between the seasonal beam changes and local gravitational variations due to groundwater, as measured by NASA's GRACE satellites. Because of the low resolution of the satellites and the short period of operation of the LHC, the correlation is not conclusive. But Hut says that if his team's work is correct, then researchers could use the LHC as the world's largest rain gauge.

Some agreeable effects of climate change mask future problems

21 April 2016
Los Angeles Times: Despite numerous studies detailing the adverse effects caused by climate change, most Americans have actually been enjoying much better weather. That is according to a recent study published in Nature. The researchers focused on the public’s experience with weather rather than on more general data, such as average temperature and precipitation measurements. The scientists found that most Americans prefer warmer winters, which is what has been occurring throughout the US since about 1974. Combined with the fact that summers have not become markedly hotter, the weather for about 80% of the US population is better than it was a half century ago. However, the researchers warn, that will change by the end of this century if greenhouse gas emissions continue unabated. To force Americans out of their complacency, the researchers suggest that climate scientists and communicators focus attention on extreme weather events, such as wildfires, droughts, floods, and hurricanes, which are already wreaking havoc on certain parts of the country as well as around the world.

IBM layoffs spread around the world

21 April 2016
IEEE Spectrum: Last month IBM started laying off an estimated 18 000 to 25 000 of its US employees, or about 20–25% of its workforce. Now reports are coming in that the company has also begun to lay off employees abroad, primarily in higher-wage countries, such as France, Germany, and the UK. Besides the 1600-some employees losing jobs in those three countries and hundreds more elsewhere in Europe, another 600 may be let go in Canada, Australia, and New Zealand. IBM’s layoffs are drawing special attention because of the company’s reticence to make the information public. Journalists and tech workers, who have been speculating on the reasons for the massive cutbacks, say that IBM may be outsourcing jobs to lower-paid workers in countries like India or removing older, more highly paid workers.

Watching biomolecules fold and unfold

21 April 2016
High-resolution measurements capture brief but informative moments in a molecule’s structural evolution.

Carl M. Shakin

20 April 2016

Sounding off on gravitational waves

20 April 2016
Ripples of gravity have a lot in common with sound waves. But let’s not oversell the comparison, says Andrew Grant in his latest Extra Dimensions post.

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