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Updated: 1 hour 7 min ago

Restricting global warming to 2°C could still bring harm

27 March 2015
New Scientist: At the climate talks that took place in Copenhagen in 2009, the world's leaders agreed to work toward limiting the globally average amount of warming to 2°C with respect to 1990. But in a new paper published in Climate Change Responses, geographer Petra Tschaker of the Pennsylvania State University advocates a target of 1.5°C. Tschaker contends that the lower target will significantly reduce the impact of climate change, especially on poor and vulnerable communities, such as the Sami people of northern Norway, Sweden, Finland, Russia's Kola Peninsula.

<em>Physics</em>, the album

27 March 2015
A search of a vast music database reveals that just three groups have ever chosen “physics” as an album name.

Black physicists and astronomers: The interviews

27 March 2015
Two students, two research astronomers, and a retired nuclear physicist talk about their professional achievements and aspirations and their love for science.

Saturnian day measured using gravitational field

26 March 2015

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.

Water squished between graphene sheets forms "square ice"

26 March 2015

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.

NASA's asteroid redirect mission is redirected

26 March 2015
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.

A stellar source of lithium

26 March 2015
To explain the observed abundance of the light metallic element, astrophysical modelers have concluded that much of it was produced in stars. But direct evidence has been lacking until now.

Episcopal bishop: Denying climate change is immoral

26 March 2015
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.

DOE adjusts its plans for nuclear waste storage

25 March 2015

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.

<em>Curiosity</em> detects nitric oxide on Mars

25 March 2015
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.

Secret Science Reform bill passes US House

25 March 2015
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.

Electrical short delays LHC restart

25 March 2015

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.

Further advances in battery technologies are needed for smart grid

25 March 2015
Lithium-ion batteries are improving too slowly to revolutionize the storage of electricity.

Attention grows for the Anthropocene, “an argument wrapped in a word”

24 March 2015
Should scientists proclaim a human geological epoch, creating a “weapon” for both sides in the “battle over the fate of the planet”?

Sound lab used to simulate and promote Heathrow expansion

24 March 2015
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.

Nonstick coating means nothing left in the bottle

24 March 2015

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.

Europe's power grid survives solar eclipse

24 March 2015

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.

Jupiter may have determined number of planets in solar system

24 March 2015
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.

Diamond steps up for thin films

23 March 2015
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.

Ukraine to join Horizon 2020 program

23 March 2015
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.

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