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News Picks

Physics Today’s online staff summarize the most important and interesting news about science from the world's top media outlets.

There are 68 posts for the selected month (March 2015).

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March 26, 2015 3:10 PM

Saturnian day measured using gravitational field

Los Angeles Times: In the early 1980s the Voyager spacecraft measured the length of Saturn's day to be 10.6 hours based on the planet's magnetic field. But when Cassini reached the planet in 2004, it obtained a different result. Subsequent measurements revealed that the planet's magnetic field, unlike Earth's, is aligned with the axis of rotation; it cannot, therefore, be used for an accurate measurement. Other techniques that attempted to use the planet's wind patterns proved even less accurate. Ravit Helled of Tel Aviv University and his colleagues have now used Saturn's gravitational field to measure the length of the day, which they found to be 6 minutes shorter than the original Voyager measurement. The technique uses the periodic changes in pull that Cassini feels as Saturn rotates as well as measurements of the planet's oblateness. The researchers confirmed the accuracy of the technique by testing it against Jupiter, whose day has a well-known length.

March 26, 2015 2:51 PM

Water squished between graphene sheets forms "square ice"

Nature: The oxygen atom in a water molecule is tightly bound to the two hydrogen atoms, but it also experiences a slight connection with the hydrogen in neighboring molecules. Because of this, as water freezes, the molecules arrange themselves into three dimensional tetrahedral shapes. Now, Andre Geim of the University of Manchester, UK and his colleagues have discovered that water pressed between sheets of graphene freezes into an ice in which the molecules form two-dimensional layers of square shapes. The structure could be the 18th different type of water ice discovered. Geim's team calculated that the pressure exerted on the water by the graphene sheets exceeds 10 000 atm or 1 gigapascal.

March 26, 2015 2:29 PM

Science: NASA announced yesterday that it would change the scope of its robotic mission to redirect an asteroid. Rather than bag a small asteroid in its entirety, a spacecraft would land on the surface of a larger asteroid and snatch a boulder. The mission, which is penciled in for a 2020 launch and is expected to cost $1.25 billion, has two main goals. The first is to test the feasibility of redirecting an Earth-threatening asteroid using the spacecraft's own gravity. The second goal is to test technologies for a manned mission to Mars by bringing the boulder closer to Earth and having astronauts visit it using NASA's new Orion spacecraft. March 26, 2015 11:55 AM Episcopal bishop: Denying climate change is immoral Guardian: In an interview with the UK's Guardian newspaper, the head of the US Episcopal Church, Presiding Bishop Katharine Jefferts Schori, asserted that denying climate change was immoral. She based her pronouncement on two lines of reasoning. First, to deny climate change is to fail to use God's gift of knowledge. Second, climate change is likely to most severely effect poor people who live in the developing world. In warning against climate change, Schori joins Pope Francis, who raised the issue last December at a meeting of the United Nations. March 25, 2015 11:37 AM DOE adjusts its plans for nuclear waste storage Nature: On 24 March Department of Energy (DOE) secretary Ernest Moniz announced that the agency was looking for a variety of temporary localized sites for nuclear waste storage. The agency will also continue its search for a permanent, geologically stable location for long-term storage of nuclear weapons waste. Moniz says that the key to the localized sites is that the agency will be seeking consent-based locations instead of attempting to force storage sites into areas where the local population does not want them. The DOE's new plan, with President Barack Obama's approval, also frees commercial and military waste to be stored in separate locations. Thanks to the policy change, waste repositories will no longer have to be equipped to store waste that has different requirements and risks. The DOE's 2016 budget proposal includes funding for an experimental borehole for long-term storage. The agency also plans to begin evaluating potential storage sites for commercial waste, but construction of such facilities would require approval from Congress. March 25, 2015 11:32 AM Curiosity detects nitric oxide on Mars BBC: NASA's Curiosity rover has detected nitric oxide (NO) in a sample that it extracted from a site in Gale Crater. The gas was released as the rover's mobile lab pulverized and heated the sample for chemical analysis. If, as the Curiosity team suspects, the nitrogen was originally in the form of nitrates before the sample was heated, the finding could have implications for the presence of life. Nitrogen is the fourth most common element in terrestrial life. Despite its high atmospheric abundance, most terrestrial species require nitrogen to be transformed first into nitrates, a task performed on Earth by soil microbes. March 25, 2015 11:28 AM Secret Science Reform bill passes US House New Scientist: Sponsored by Rep. David Schweikert (R-AK), the Secret Science Reform Act would, in the words of its summary, "prohibit the Administrator of the Environmental Protection Agency (EPA) from proposing, finalizing, or disseminating a covered action unless all scientific and technical information relied on to support such action is specifically identified and publicly available in a manner sufficient for independent analysis and substantial reproduction of research results." Last week, the House of Representatives passed the bill, whose supporters claim it would make the regulation of oil and gas extraction more open to the public. The bill's detractors, however, claim it would make protecting the environment more difficult. March 25, 2015 11:11 AM Electrical short delays LHC restart Science: The Large Hadron Collider (LHC) at CERN was planned to begin circulating beams of particles the entire way around the accelerator's 27-km circumference this week. However, an electrical short discovered over the weekend has delayed the full restart while the short is repaired. That task could take as little as a few days or as long as several weeks. Shorts are not uncommon as the LHC is slowly ramped up, but the time it takes to repair them can be significantly increased if supercooled electronics first have to be warmed up. The scientists working at the accelerator plan to use x-ray imaging to examine the area to determine if they can remove the metallic source of the short by melting it or blowing it away with helium. March 24, 2015 2:25 PM Sound lab used to simulate and promote Heathrow expansion Guardian: The prospect of a third runway at the UK’s busy Heathrow Airport has many local residents upset because of the potential for even more noise. To help mitigate people’s fears, Arup SoundLab in central London has simulated what the proposed expanded airport would sound like. In the lab, technicians can re-create different scenarios that include various combinations of aircraft, times of day, and distances from the airport. Because older, noisier planes are being phased out and newer, quieter planes are being introduced, the lab is also set up to compare current and future sound scenarios. Heathrow officials suggest that the new runway, which will require steeper landing approaches and keep planes flying higher for longer, may even provide some respite from the noise. March 24, 2015 1:26 PM Nonstick coating means nothing left in the bottle New York Times: Getting the last of anything out of a bottle usually involves scraping the inside. Depending on the viscosity of the substance, up to a quarter of the contents of a bottle may end up being thrown out. Now, Kripa K. Varanasi of MIT and graduate student J. David Smith have created a startup, called LiquiGlide, to market a coating they developed that allows a bottle's contents to easily slide out, regardless of the viscosity. Thanks to its porous surface, their material traps a lubricant that can be customized to best match the properties of the intended contents of the bottle. The lubricant makes the inner surface of the container superhydrophobic, which prevents the contents from binding to the container's interior. March 24, 2015 12:05 PM Europe's power grid survives solar eclipse New Scientist: Last week's solar eclipse was visible across much of Europe. That meant that the solar generating capacity of many countries was reduced briefly and other energy sources needed to be deployed. Since 2006, the European Union has spent €3 billion ($3.28 billion) on developing smart-grid technologies to help balance the distribution of energy in response to fluctuations in demand or production. In Germany, for instance, which gets 26% of its power from solar and wind, last week's eclipse provided an important test of the grid's ability to handle sudden changes. To be on the safe side, the country doubled its network staff for the day and also turned off four aluminum plants that draw a lot of power. During the eclipse, Germany's solar energy production dropped from 38.2 GW to 23.2 GW. No problems were reported, however, in either Germany or any of the countries that contribute the other 51 GW of solar power in the EU.

March 24, 2015 12:05 PM

Jupiter may have determined number of planets in solar system

Los Angeles Times: Our inner solar system is unusual in that it has far fewer planets than most other planetary systems discovered so far. Why it is not crowded with so-called super-Earths, planets with masses exceeding those of Earth, may be due to Jupiter, whose early orbit of 3–10 astronomical units from the Sun varied wildly before settling in to its current one of 5–5.5 AU. A group of researchers has proposed that in the early solar system, a young Jupiter may have migrated toward the Sun, sweeping along many of the other, smaller objects around it. In the process, those objects may then have collided with each other, broken up into dust, and drifted along into the Sun. As Jupiter reversed course and settled in to its current orbit, the remaining debris formed into the solar system’s terrestrial planets. The discovery of more exoplanetary systems should help determine whether that scenario is likely.
March 23, 2015 3:25 PM

Diamond steps up for thin films

MIT Technology Review: Diamond possesses remarkable physical properties—it is strong, transparent, and thermally conductive. Hence, thin films made from diamond could be extremely useful in various electronic and mechanical micro- and nanodevices. However, growing diamond thin films requires stringent conditions, including high temperatures and an atmosphere of pure hydrogen. Now a group of researchers has shown how diamond nanosheets can be grown on a substrate of quartz and then transferred elsewhere as needed. At a thickness of about 180 nm, the diamond separates naturally from the quartz and can be moved and attached to another surface, such as an electronic circuit, through the use of a sticky film. Because it is so labor-intensive, the current technique is not yet viable for mass production of diamond-based devices.
March 23, 2015 2:30 PM

Ukraine to join Horizon 2020 program

Nature: Ukraine is set to become an associate member of the European Horizon 2020 program, once the country’s parliament votes to approve the agreement. Horizon 2020 is the world’s largest multinational funding program dedicated to research and innovation. Over the period 2014 to 2020, it will make available some €80 billion in science funding. It is the first European Union (EU) program in which Ukraine has chosen to participate since the signing of the Ukraine–European Union Association Agreement in 2014. Membership will allow Ukrainian scientists, research institutions, and enterprises to compete with EU member states for funding. In addition, Ukraine will be able to host European Research Council (ERC) grant recipients and participate in the program’s governance.
March 23, 2015 12:20 PM

Large Hadron Collider's second run to start this week

BBC: The Large Hadron Collider (LHC), at CERN in Switzerland, is about to begin phase two of its operations. Phase one began in 2008, when the LHC fired its first protons, and lasted until early 2013. Since then, the world’s largest and most powerful particle collider has been undergoing a period of maintenance and upgrades. Each of its 10 000 superconducting electromagnets has been inspected and reinforced to withstand the extreme conditions meant to simulate those that occurred shortly after the Big Bang. At the same time, most of the LHC's seven detectors have also been undergoing service and upgrading. They've been prepared for the return of the proton beams, which will have nearly twice the collision energy of those during the first run. The restart will be a gradual process, with the proton beams reaching full circle no earlier than Wednesday.
March 23, 2015 11:50 AM

Earth’s tectonic plate motion is jittery

Science: Earth’s continents are continually shifting, and the pace of their movement is irregular, sometimes rapid and sometimes slow. Researchers at the EarthByte program at the University of Sydney in Australia have been studying the complex interplay between deep-Earth and surface processes and have developed a computer model that breaks down tectonic plate movements into 1-million-year intervals. They have found that although the plates tend to shift about 4 cm per year, they can move as fast as 20 cm per year over geologically brief time periods of 10 million years or so. And oceanic plates appear to move faster than continental plates. What causes the plates to speed up and slow down is still not entirely understood. The researchers say that rising plumes of molten rock in Earth’s mantle could provide lubrication between it and the continents, and rocky protrusions on the underside of the massive continents may create drag to slow them down. The group plans to look next at ancient plate movement before the breakup of Pangea into multiple continents.
March 20, 2015 2:00 PM

Moon's ice indicates past polar shift

Science: At the Lunar and Planetary Science Conference this week, an unexpected finding about the location of the Moon's ice was announced. Unlike the ice found on most planetary bodies in the solar system, the Moon's ice does not cover its north and south poles, but rather is located several degrees away from its poles. Matthew Siegler of the Planetary Science Institute in Dallas, Texas, and his colleagues reexamined data collected by the Lunar Prospector mission, which orbited the Moon 16 years ago. They realized that the two patches of lunar ice were directly opposite each other. The most likely explanation for this arrangement is that the ice was originally deposited at the lunar poles, and at some point, the Moon's axis must have shifted by more than 5°. None of the known asteroid impacts are large enough or in the right location to have been the cause. Siegler's team believes the outpouring of lava that created the Oceanus Procellarum some 3.5 billion years ago could have unbalanced the axis.

March 20, 2015 12:50 PM

EU and China to choose first joint space project

Nature: On 16 March, the European Space Agency (ESA) and the Chinese Academy of Sciences closed a call for proposals for a joint space mission. The ESA has contributed instruments to a Chinese satellite before, but this will be the first mission to be a collaboration from the start. The two agencies are each contributing the equivalent of just over \$53 million to the project, a funding amount that limits its size. Another limitation is that the mission should focus on something other than Mars or the Moon, which are already being studied through other projects. The agencies received 16 proposals, which included studying radio signals, x-ray imaging of Earth's magnetosphere, and looking at "hot objects" with an extreme-UV telescope. The proposals will be examined based on technological feasibility and scientific merit. By the end of the year, the best will be selected to undergo further review, with a final decision to be made in 2017.

March 20, 2015 12:40 PM

Green-glowing fungi attract more bugs

Los Angeles Times: Although bioluminescence has been observed in fungi, it is relatively rare. Among the some 100 000 known fungal species, just 71 have the ability to glow like fireflies. Rather than constantly emitting green light, however, at least one species—Neonothopanus gardneri—appears to be regulated by the circadian clock, according to a recent study published in Current Biology. N. gardneri glows brilliantly at night and shuts off during the day. The reason may have to do with the attraction of insects, which could help spread the fungi’s spores in the dense Brazilian coconut forests where they grow. The researchers tested their theory through the use of prosthetic, acrylic-resin, mushroom-shaped objects artificially illuminated with green LEDs. The fake mushrooms attracted many more beetles, ants, and other insects than did the dark control traps.
March 20, 2015 10:40 AM

Record low reported for Arctic sea ice

BBC: This year the maximum level of sea ice in the Arctic Ocean, as measured on 25 February, was found to be 130 000 km2 below the previous record low, which was set in 2011. Since satellite records began in the late 1970s, the annual mean Arctic sea-ice thickness has decreased by 65%, according to a recent study. Although the Arctic Ocean will continue to freeze each winter and thaw each summer, regardless of climate change, scientists are observing a fairly clear pattern of substantial sea-ice loss over time. The consequences could prove profound for people, animals, and plants not only in polar regions but also around the world, said Bob Ward of the Grantham Research Institute on Climate Change and the Environment at the London School of Economics.
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