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Updated: 2 hours 35 min ago

Extracurricular activities drive this teacher—and his students

29 June 2016
From dripping faucets to Dubai friendships, Mark Vondracek puts his energy into teaching.

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29 June 2016

US, Canada, and Mexico agree to produce half their energy from renewables by 2025

29 June 2016

Guardian: At a meeting in Ottawa, Canada, this week, Barack Obama, Justin Trudeau, and Enrique Peña Nieto will commit to a plan to have the US, Canada, and Mexico produce half their electricity from hydropower, wind, solar, and nuclear plants by 2025. That represents a large increase from the current collective clean power levels of about 37%. The agreement will also include plans for carbon capture and storage and energy efficiency measures. Because the US accounts for 75% of the three countries' energy production and only one third of its production is from clean energy, it will have the most work to do to reach the stated goal. A Supreme Court ruling earlier this year halted Obama's attempt to reduce coal plant emissions to meet emissions targets set at the 2015 Paris climate conference. Although Mexico currently produces less than 20% of its electricity from clean sources, Canada gets 81% of its power from renewables.

Traversing a hypothetical tunnel through the center of the Earth

29 June 2016
Science News: In a recent thought experiment, Thomas Concannon and Gerardo Giordano of King’s College in Pennsylvania explore what it would be like to fall down a hole through Earth’s center to the other side. Because of the complexity of the problem, researchers in the past have simplified the calculations by making some broad assumptions, including that Earth has a uniform density and doesn’t rotate and that there is no drag from air resistance or friction along the tunnel’s sides. To create a more realistic model, Concannon and Giordano have now included drag forces in their calculations. They found that it would take at least 1.8 years just to reach Earth’s center through an air-filled tunnel. By evacuating the air, the total trip time to Earth’s center could be shaved down to just 19 minutes. But because of friction, it would never be possible to overcome gravity’s pull and make it to the other side.

Virginia R. Brown

29 June 2016

VW faces largest US civil settlement ever

29 June 2016
Bloomberg: Because of Volkswagen’s attempt to rig environmental tests on its diesel vehicles, the car manufacturer may have to pay out some $15 billion to settle all the lawsuits in the US alone. Up to $10.03 billion is to cover costs including buying back vehicles and compensating the owners. Some $2.7 billion will be paid as fines to the US Environmental Protection Agency and the California Air Resources Board, and about $2 billion will be invested in clean-emissions technology. Another $400 million will go to settlements with states, including New York. Whether VW has set aside enough money to cover all the fallout remains to be seen, as the company still faces civil and criminal actions in other countries spanning three continents.

NASA performs test-fire of SLS rocket booster

29 June 2016
Space.com: On 28 June, NASA successfully test-fired its Space Launch System (SLS) rocket booster engine in Promontory, Utah. The two-minute burn of the 3.6-million-pound-thrust engine is the last live firing for the booster until NASA performs its first SLS rocket launch in 2018. On that Exploration Mission 1, the SLS will carry an uncrewed Orion capsule on a flight around the Moon and back to Earth. For launches, the SLS will use two booster engines alongside the rocket's core stage.

Nighttime blue-light LEDs cause health problems, AMA warns

28 June 2016
The shift to LEDs for residential street lighting is creating a host of medical and environmental problems, a new report says.

NASA prepares for <em>Juno</em> spacecraft’s arrival at Jupiter next week

28 June 2016
New York Times: On 4 July the US will celebrate not only Independence Day but also the arrival of NASA’s Juno spacecraft at Jupiter. Launched five years ago, Juno has traveled nearly 3 billion kilometers. Whereas the Galileo spacecraft, launched in 1989, spent eight years exploring Jupiter and its moons, Juno will concentrate on the planet itself, particularly on what lies beneath its dense cloud cover. Besides abundant hydrogen and helium, Jupiter is thought to contain small amounts of heavier elements, such as carbon, lithium, and nitrogen. The data gathered should provide insight into how the solar system and the planets formed.

New helium source discovered in Tanzania

28 June 2016
New Scientist: Some 1.53 billion cubic meters of helium has been discovered beneath the Great Rift Valley in Tanzania. Because of helium's many uses in scientific and medical research, and in novelty balloons, the world’s supply has been dwindling. To date, all helium had been found by accident. Now Chris Ballentine of Oxford University and colleagues have deliberately tracked down helium for the first time. They identified the Tanzania site after looking for rock that contains the necessary radioactive ingredients that decay into helium and for underground caverns that could have trapped the resulting gas. Although the researchers have shown that prospecting for helium is possible, they emphasize that the supply will eventually prove finite.

Arid California may have unexpected underground water resource

28 June 2016
Washington Post: Some relief may be in sight for drought-ridden California: Researchers at Stanford University say there could be as much as 2700 billion tons of freshwater lying in aquifers some 3000 meters below the ground. The scientists base their finding on data from nearly 35 000 oil and gas wells. Although the water could be somewhat salty, they say, desalinating it would probably be cheaper than desalinating the much saltier seawater a new San Diego plant now draws from the Pacific Ocean. The study may prove controversial, however, because the exact quantity, quality, and depth of the water are not known, nor whether the water will prove economical to pump. In addition, some of the water may have been contaminated by hydraulic fracturing activities and wastewater disposal by the oil and gas industry.

Former EU science adviser “very pessimistic” after Brexit vote

28 June 2016
Science: In a Q&A with former European Union (EU) science adviser Anne Glover, the Scottish biologist discusses the recent vote by the UK to withdraw from the EU. Glover expresses dismay over the decision and believes it was based on prejudice concerning immigration rather than on factual evidence. She says that UK science and research benefited enormously from EU membership. She adds that Scotland may hold its own referendum to withdraw from the UK and remain in the EU.

Xenon chemistry under pressure

27 June 2016
Diamond-anvil-cell experiments and ab initio models confirm that at high pressure and temperature, xenon bonds with oxygen to form a host of stable oxides.

As British leaders look to slow things down, EU leaders may push for faster exit

27 June 2016

Washington Post: Both David Cameron, who announced that he will step down as prime minister in October, and leading proponents of the UK's departure from the European Union have called for a delay in beginning the country's formal exit. Cameron has said that he would leave the invocation of Article 50 of the Lisbon Treaty to his successor and that the exit has to be officially approved by Parliament. However, some officials, such as France's finance minister Michel Sapin, have suggested that the UK should begin the process as soon as possible. Angela Merkel says she is against conducting informal negotiations that might give the UK more time, but a foreign policy official indicated that the German chancellor might be more accommodating if the UK seriously reconsiders its exit decision.

Researchers fully model the early universe with general relativity

27 June 2016

Nature: Einstein's general relativity has been used to model the expansion of the early universe, but only in a simplified form. The complexity of the equations requires the assumption that matter was uniformly distributed in the early universe, which likely does not match reality. Even after the development of supercomputers, calculations continued the simplification for models that extended beyond a small region. Now two groups have independently created full-universe simulations that include a non-uniform distribution of matter. One group—led by Eloisa Bentivegna of the University of Catania, Italy, and Marco Bruni of the University of Portsmouth, UK—developed a model to study the formation of large, superdense structures. The model developed by the other group—led by Glenn Starkman of Case Western Reserve University in Cleveland, Ohio—focuses on how the universe expands and how its curvature affects the propagation of light. Both groups' models used numerical-solution techniques that were developed for calculating the warping of spacetime caused by black hole pairs like those that created the recently detected gravitational waves.

NASA plans to extend <em>Hubble</em> mission through 2021

27 June 2016

New Scientist: On 23 June, NASA announced that it intends to continue using the Hubble Space Telescope through June 2021. Launched in 1990 and last serviced in 2009, Hubble can easily continue working into the 2020s, NASA says. The extension of Hubble means the telescope will still be in use when its successor, the James Webb Space Telescope (JWST), is launched in 2018. Using the two telescopes in tandem will provide a valuable opportunity to study objects with Hubble's visible and UV cameras and JWST's IR cameras.

Brexit vote rattles UK and European scientists

24 June 2016
The UK’s decision to leave the European Union leads to concerns over funding and collaboration.

Arthur J. Freeman

24 June 2016

Quantum computer used for high-energy physics simulation

23 June 2016

Nature: Simulations of phenomena involving the strong nuclear force are too hard to perform from first principles on classical computers. Now Esteban Martinez of the University of Innsbruck in Austria and his colleagues have used a quantum computer to complete a proof-of-concept simulation of the conversion of energy into an electron and positron pair. It's the first time a quantum computer has been used to simulate a high-energy physics experiment. The simulation matched the predictions of a simplified form of quantum electrodynamics. The quantum computer contained four qubits in a linear arrangement. Martinez's team now hopes to use a two-dimensional arrangement of qubits and scale up the simulation.

Conservative media sustain alarm about a possible electromagnetic-pulse catastrophe

23 June 2016
National Review and others emphasize an “existential threat” in an EMP from a high-altitude nuclear burst—but solar activity stirs the fear too.

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