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Updated: 53 min 54 sec ago

NASA performs test-fire of SLS rocket booster

29 June 2016 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.


23 June 2016

Imaging small proteins for drug discovery

23 June 2016
Cryoelectron microscopy, despite a flurry of recent progress, has until now been limited to large biomolecules.

Square Kilometre Array telescope faces community pushback in South Africa

22 June 2016

Nature: The Square Kilometre Array (SKA) is an international radio telescope being built in Australia and South Africa. Construction of the first of 197 radio dishes has already begun in South Africa's Northern Cape province, a sparsely populated area of mostly farmland. The SKA project is now facing protests from local residents as the organization begins to purchase more land to construct the majority of the dishes. The SKA organization's initial outreach to the community focused on how the project would create jobs and improve economic and educational opportunities. It currently is providing support for new teachers in nearby Carnarvon and is paying tuition for some students to attend universities. But the benefits have not been evenly distributed among the local communities. Additionally, residents are concerned that the loss of farmland will damage the local economy.

US weather model down to fourth best in the world

22 June 2016

Ars Technica: Over the past several years, the success of the US's Global Forecasting System (GFS) weather model has been challenged by the rise of other models, such as one put out by the European Centre for Medium-Range Weather Forecasts. The competition between models first reached broad popular awareness in 2012, when the European model more accurately predicted the behavior of Hurricane Sandy. In a widely accepted measurement of forecast accuracy, the GFS model has now fallen behind not only the European model but also models from the UK and Canada, based on predictions over the past two months in the Northern Hemisphere. According to Cliff Mass of the University of Washington, the drop in ranking isn't because the GFS model is failing but because the other models have improved significantly.

California's last nuclear power plant will close by 2025

22 June 2016

NPR: The Diablo Canyon Nuclear Power Plant is the last nuclear plant still operating in California. On 21 June Pacific Gas and Electric announced that it would close the plant by 2025 and replace it with renewable energy sources. Diablo Canyon provides energy to 1.7 million homes. Local residents and environmental groups have continually raised safety concerns because the plant and its two nuclear reactors are close to active fault lines. Protests intensified following the earthquake and tsunami that damaged Japan's Fukushima Daiichi Nuclear Power Plant in 2011.

Newly spotted exoplanet is in its infancy

21 June 2016

GeekWire: Trevor David of Caltech and his colleagues have spotted an intriguing planet orbiting K2-33, a star in the field of view of the Kepler space telescope during its extended K2 mission. The planet has a diameter about six times that of Earth, and it orbits its star every 5.4 days at a distance of 7.4 million km. Further examination of the system revealed that the star is still surrounded by gas and dust from the protoplanetary disk. The presence of the disk's remnants suggests that the planet is less than 10 million years old, since models of planetary system evolution predict that disks dissipate fairly quickly. Now researchers have to figure out why the youthful planet is so close to its star; most models suggest that large planets form far away and then migrate inward later.