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Updated: 10 min 37 sec ago

Climate scientist dies in snowmobile accident in Antarctica

8 hours 26 min ago
New York Times: Climate scientist Gordon Hamilton died on 22 October in Antarctica when his snowmobile fell into a crevasse. Hamilton, who was 50 years old, was an associate research professor in the glaciology group of the Climate Change Institute at the University of Maine. His work centered on how ice sheets behave and affect the climate system. Hamilton and his research team were camped on White Island in the Ross Archipelago in a heavily crevassed area known as the Shear Zone. The cause of the accident is currently under investigation.

Harry Dahl Holmgren

9 hours 33 min ago

Likely <em>Schiaparelli</em> crash site spotted by <em>Mars Reconnaissance Orbiter</em>

10 hours 17 min ago

BBC: NASA's Mars Reconnaissance Orbiter (MRO) has taken a picture of the area where the European Space Agency's Schiaparelli probe is believed to have crash-landed on Mars. Schiaparelli ceased communications during its descent, and data from before contact was lost suggest that the probe's landing systems did not operate properly. In the MRO imagery, a dark patch roughly 15 m × 40 m is visible about 5.5 km west of the probe's planned landing site; previous images show no such mark. The dark patch is likely debris thrown up by the impact. Additionally, the MRO may have spotted the lander's 15-m-wide parachute about 1 km south of the probable crash site.

Despite the challenges, crewed Mars missions are on the horizon

21 October 2016
National Geographic: Because Mars is one of the closest planets to Earth, it may be the next frontier for human exploration. However, it is some 55 million km away, and such a long journey through space poses numerous challenges, including designing a spacecraft that could shield the astronauts from cosmic rays, provide enough space to keep them comfortable, and store enough food and supplies. In addition, space’s zero gravity has a detrimental effect on human bone and muscle mass over time and causes the body to retain fluids in the brain and elsewhere. Nevertheless, some space agencies and private companies are planning future crewed missions to the Red Planet. Whereas NASA is working to send astronauts into orbit around Mars by the 2030s, Elon Musk, founder and CEO of SpaceX, has set his sights on the ambitious goal of actually landing humans on the planet's surface by 2024. This National Geographic article looks in depth at the current technology and costs and explores possible scenarios for colonizing Mars.

Ancient shipwrecks found at the bottom of the Black Sea

21 October 2016
New Scientist: Submersibles for the Black Sea Maritime Archaeology Project have discovered 41 shipwrecks lying on the bottom of the seabed. The ships’ remains, some more than 1000 years old, have been well preserved by the anoxic, or low-oxygen, conditions, which prevent the decay of the wood and other natural materials. Rudders, masts, tillers, and even ropes can be seen in high-quality images taken using 3D photogrammetry. Because of their location far out at sea, the ships were more likely trading vessels than battleships, says Jon Adams of the University of Southampton, UK, principal investigator on the project.

Dissecting the rapid intensification of Hurricane Patricia

21 October 2016
A year ago a modest-looking tropical cyclone unexpectedly strengthened into the most intense hurricane ever recorded. A confluence of favorable conditions explains why.

A map of Earth’s viscous crust

20 October 2016
In an adaptation of an old imaging method, the electrical resistivity of rock is used as a proxy for its mechanical strength.

First US nuclear reactor in two decades goes live in Tennessee

20 October 2016

Chattanooga Times Free Press: On 19 October, the Tennessee Valley Authority (TVA) officially connected the Unit 2 reactor at the Watts Bar Nuclear Power Plant to the electrical grid. Watts Bar Unit 2 is the first nuclear reactor to be added to the US's power system in 20 years. The last reactor added was the plant's Unit 1, which opened in 1996. The $4.7 billion reactor started generating power in May but has been undergoing tests and evaluations ever since. It is the TVA's seventh nuclear reactor. Together the TVA's seven reactors provide nearly 40% of the regional utility's power generation. Unit 1 and Unit 2 each provide 1150 MW. The TVA has no plans to construct more reactors, however, because regional electricity demand has leveled off. Unit 2 will serve as a replacement for older coal plants that have been closed.

Contact lost with <em>Schiaparelli</em> lander on its way to Mars’s surface

20 October 2016
New York Times: The ExoMars mission suffered a setback yesterday after its Schiaparelli lander separated from the Trace Gas Orbiter and began its descent to Mars’s surface. Although the lander appears to have successfully deployed its parachute and heat shield, it stopped transmitting signals shortly before its scheduled landing. A board of inquiry now plans to sift through the data to find out what went wrong. Nevertheless, the European Space Agency, which collaborated with the Russian space agency Roscosmos on the mission, still considers the project to be a success because the orbiter is in place and already transmitting data. Despite the lander’s loss, the ExoMars mission should still be able to fulfill its primary goal of preparing for a more ambitious Mars mission in 2020.

German experiment to measure neutrino mass begins

19 October 2016

International Business Times: On 14 October, researchers at the Karlsruhe Institute of Technology in Germany turned on the Karlsruhe Tritium Neutrino (KATRIN) experiment. The €60 million ($66 million) facility houses a 220 ton spectrometer that will be used for the next five years to attempt to measure the exact mass of neutrinos. In the standard model of particle physics, neutrinos were predicted to be massless; however, the discovery that neutrinos have different flavors and oscillate between them suggests that the particles do have mass. Whereas electrons have a mass of 511 000 eV, neutrinos may have a mass of just 2 eV. KATRIN, which has a sensitivity of 0.2 eV, is designed to find a precise measurement of neutrino mass by studying the particles that are released by the decay of tritium atoms. Guido Drexlin, one of KATRIN's spokespersons, says that the research team hopes to have clear data to present as early as sometime next year.

Roof collapses lead to section closures at US waste isolation plant

19 October 2016
Albuquerque Journal: Problems continue at the Waste Isolation Pilot Plant located near Carlsbad, New Mexico. The Department of Energy is now planning to close off the south end of the nuclear waste repository because of a series of roof collapses over the past year. The WIPP is still recovering from a major radiation leak in 2014, which caused a nine-month shutdown and construction delays because of additional safety measures and requirements for protective clothing for workers. Sealing off part of the repository will reduce the WIPP's storage capacity, but by how much has yet to be determined.

Russia abandons plutonium destruction pact with US

19 October 2016
US says it remains committed to disposing of 34 metric tons of plutonium that has been declared surplus to weapons needs.

Critics condemn restrictions forced on science media

18 October 2016
They charge that with covert "close-hold embargoes," the FDA and others hobble reporters' access to sources.

Orbital ATK rocket launches successfully on ISS resupply mission

18 October 2016 On 17 October an Orbital ATK rocket blasted off at 7:45pm EDT from NASA’s Wallops Flight Facility on Wallops Island, Virginia. Its uncrewed Cygnus cargo capsule is carrying 2300 kg of science experiments, hardware, and other supplies to the astronauts on the International Space Station (ISS). The successful launch was especially important for Orbital ATK because its last Antares rocket had exploded on the pad two years ago. Clear night skies allowed the launched rocket to be visible along the US East Coast, from Boston to South Carolina. Because of weather and issues with a ground support cable, the Cygnus spacecraft's launch had been delayed by several days. The craft's arrival at the ISS will now coincide with that of a Russian capsule carrying three astronauts, so Cygnus will have to wait to dock.

Robert E. Behringer

18 October 2016

Billion-dollar radar installation could be threatened by rising sea levels

18 October 2016
Associated Press: To track space debris in orbit around Earth, the US Air Force is building a $1 billion radar installation on Kwajalein Atoll in the Marshall Islands. The Space Fence facility is being constructed by Lockheed Martin, which won the contract in 2014 and began construction last year with the goal of completion by late 2018. But the atoll rises just 3 m above sea level. According to Curt Storlazzi of the US Geological Survey, many islands in the atoll will be completely submerged by storms multiple times a year within just a few decades. The saltwater would pose a significant threat to electrical systems and other hardware. Dana Whalley, who is managing the Space Fence program, says that the facility has a projected lifespan of only 25 years. Sea walls should be able to protect the facility during that time scale, Whalley says.

US Navy closes major deal on solar power

17 October 2016
Washington Post: As of 14 October, Arizona’s Mesquite 3 solar array has been switched on and has started powering some 14 naval installations in California. Owned by Sempra Energy, the 150 MW facility will provide about one-third of the US Navy bases’ electrical needs at a fixed price for the next 25 years. The largest renewable-energy procurement ever by the federal government, the deal represents a clean-energy milestone for the US. Since 2010 the US has built about 50 large-scale solar photovoltaic facilities, the first five of which were financed by the Department of Energy. Energy secretary Ernest Moniz credits the DOE program with helping to drive down the cost and jump-start the solar power boom. Although solar power currently provides just 1% of total US electricity capacity, solar power generation has jumped from 20 MW before 2009 to some 31.6 GW today.

Micromotors swim toward and away from the light

17 October 2016
UV radiation spurs a redox reaction that propels micro-sized swimmers in a predetermined direction.

China sends two astronauts on country's longest space mission

17 October 2016

New York Times: Early Monday morning local time, China's space agency launched two astronauts aboard the Shenzhou-11 spacecraft on a mission to dock with the Tiangong-2 space lab, which the agency put into orbit last month. The astronauts are scheduled to spend 30 days aboard the orbital lab, which will more than double the duration of the previous longest mission by a Chinese astronaut. The mission is the sixth crewed mission by China. Aboard Tiangong-2, astronauts Jing Haipeng and Chen Dong will test computers and station equipment and conduct other experiments. China hopes to launch a longer-lived station, Tianhe-1, in 2018.