Physics Today Daily Edition

Subscribe to Physics Today Daily Edition feed
Please follow the links to view the content.
Updated: 56 min 30 sec ago

Insect wings could serve as radiation dosimeters

6 May 2016
New Scientist: Dragonflies, houseflies, and other insects may one day be used to help gauge radiation levels at nuclear power plants and after nuclear incidents. Ionizing radiation causes electrons in the atoms of the insects’ wings to be ejected. The resulting holes can act as particles, which then move around the electrons. When exposed to UV light, the holes and electrons can recombine; when they do, a flash of light is emitted. Now Nikolaos Kazakis of the Athena Research Center in Greece and colleagues have tested the radiation sensitivity of several types of winged insects by exposing them to different doses, shining a light on them, and measuring the flashes. Because insects are short-lived, they are mostly uncontaminated by natural radiation. Although the researchers were able to measure exposures of 10–2000 Gy, the technique was not sensitive enough to detect lower radiation exposures. In addition, any exposure to sunlight reduced its effectiveness. However, say the researchers, the technique could still have its uses. And because insects are ubiquitous, there will always be plenty to be found in dark places such as air ducts and basements.

SpaceX lands rocket on ship at sea for second time

6 May 2016
Mashable: Earlier today SpaceX landed its first-stage Falcon 9 rocket on a drone ship in the Atlantic Ocean for the second time. The private aerospace company has attempted the feat six times so far, the last two of which have been successful. It has also landed the rocket on land once. A sea landing is preferred because it requires less fuel. Besides further demonstrating that the rocket can be recovered and reused, the mission successfully carried a Japanese communications satellite into orbit. After the landing, company CEO Elon Musk tweeted that the landing used three engines and had triple the deceleration of the previous flight. The ability to slow down quickly before landing would be useful for a future Mars expedition because of that planet’s thin atmosphere.

Chaos limits predictability of hurricane intensities

5 May 2016
If a butterfly sets off a hurricane halfway around the world, how well can we forecast the storm's strength?

Surgical robot performs first autonomous procedure

5 May 2016
GeekWire: The Smart Tissue Autonomous Robot (STAR) has succeeded in sewing up the ruptured intestines of four live piglets. STAR uses near-IR imaging to gauge the surgical site, a computer program to develop a surgical procedure, and a robotic arm to suture the cut ends together. Monitored by a team of human surgeons, STAR was able to operate fully autonomously about 60% of the time. Although STAR surpassed most human surgeons in quality of work, based on the spacing of the stitches and the tension on the sutures, it required twice the amount of time. Nevertheless, the experiment has been deemed an important proof of concept. Such robot surgeons would have several uses, including making the best surgical techniques more widely available and allowing difficult medical procedures to be carried out in isolated environments such as Antarctica or future outposts in deep space.

Machine learning algorithm creates successful chemical reactions from failed experiments

5 May 2016
Nature: Machine learning algorithms have been used to help create complex molecules based on input of known successful reactions. Now Alex Norquist, Sorelle Friedler, and Joshua Schrier of Haverford College in Pennsylvania and colleagues have included unsuccessful experiments in the data provided to a computer algorithm that predicts whether a specific set of reagents will react to form a crystalline material. The researchers provided the algorithm with data from nearly 4000 experiments, including both published successes and failed reactions, which they had to transcribe from unpublished notes. The team then asked the computer to identify the principles that distinguished the successful reactions from the failures. When subsequently provided with previously untried combinations of reactants, the algorithm suggested nearly 500 reactions, 89% of which resulted in a crystalline product. In comparison, the educated guesses of the researchers were successful only 78% of the time.

Explanation found for 2011 earthquake on US East Coast

5 May 2016

Gizmodo: The magnitude 5.8 earthquake that struck northern Virginia in 2011 was notable because of the extreme rarity of earthquakes in that region—it was the strongest earthquake east of the Rocky Mountains since 1944. The East Coast of the US is far from the edges of the North American tectonic plate, where interactions with neighboring plates trigger seismic activity. Now Berk Biryol of the University of North Carolina at Chapel Hill and colleagues believe they have found an explanation for the 2011 earthquake. Biryol's team used seismic activity from around the globe to construct a 3D map of the bottom of the North American plate. The researchers found that the southeastern part of the plate is heavily fractured and encompasses thin and thick sections of crust and mantle. Based on their map, the scientists argue that chunks breaking off the bottom of the plate could trigger earthquakes. The mechanism could explain other major seismic events such as the magnitude 8.1 earthquake that struck New Madrid, Missouri, and the 7.0 earthquake that struck Charleston, South Carolina, in the 1800s.

Canadian wildfire fueled by climate change

5 May 2016
Climate Central: On Tuesday some 80 000 residents of the city of Fort McMurray in Alberta, Canada, and the surrounding area were forced to evacuate when a wildfire lit up the skies and thick smoke filled the air. Unusually warm weather, with temperatures soaring into the 90s, and high winds helped fuel the flames. The fire, which has forced the largest evacuation in the area to date, is part of a growing trend. In Canada, wildfires are starting a month earlier and the average annual burn area has doubled since 1970, according to Mike Flannigan of the University of Alberta. Flannigan blames climate change, which has been causing drier winters and earlier spring snowmelt. A single wildfire in Canada can have global impacts because of the tons of carbon pollution that can be released into the atmosphere, which causes further warming and increased fire risk.

Stop falling in love with the latest Earth-like planet

5 May 2016
Extra Dimensions: Too many variables exist to confidently single out any newly discovered exoplanet as the go-to extrasolar destination.

IBM proclaims “the beginning of the quantum age of computing”

4 May 2016
Reporters consider IBM’s Quantum Experience website, designed to “allow students, hobbyists and even serious researchers to experiment.”

Michael Watkins chosen as next director of JPL

4 May 2016

Los Angeles Times: On Monday, Charles Elachi, the current director of NASA's Jet Propulsion Laboratory (JPL), announced that Michael Watkins will succeed him beginning 1 July. Watkins, a 22-year veteran of JPL, is currently the director of the Center for Space Research at the University of Texas at Austin. While at JPL, Watkins served as mission manager for the Martian rover Curiosity and project manager for the Gravity Recovery and Interior Laboratory (GRAIL) and Gravity Recovery and Climate Experiment (GRACE) missions. He was also manager of the lab's science division and chief scientist for the engineering and science directorate.

IBM makes a quantum processor available for use online

4 May 2016

IEEE Spectrum: This morning, IBM announced it was making a five-qubit quantum processor available online for anyone to use. Jay Gambetta, manager of IBM's Theory of Quantum Computing and Information Group, says the project's goal is to get people thinking about how a quantum computer works. Toward that end, the IBM Quantum Experience includes tutorials and a visual programming interface; no knowledge of a particular programming language is required. Users will be able to learn about various algorithms and run actual operations on the quantum system. However, a classical simulation of this particular system is actually faster. The project expects to have the processor available 24/7, with intermittent downtime for maintenance.

Despite creation of graphene institute, UK falls behind in commercialization

4 May 2016
Nature: Construction of the National Graphene Institute (NGI) at the University of Manchester in the UK was completed last year, but already questions have been raised concerning its viability. The NGI is considered the “home of graphene” because of the work of Nobel Prize–winning Manchester physicists Andre Geim and Kostya Novoselov, who first isolated the atom-thin carbon material. However, after some issues were raised by the Sunday Times newspaper in March, a parliamentary inquiry revealed that since its initial investment in the building of the NGI, the UK has failed to provide adequate funding to fully exploit graphene’s commercial potential. Among the reasons is that the UK lacks the necessary industrial base and holds less than 1% of the world’s graphene patents. Although the UK plans to add a second graphene center at the university, critics say it must do more to boost commercial investment and development.

Offshore drilling of dinosaur-killing impact crater yields crucial samples

4 May 2016
Science: In April the first offshore drilling of the Chicxulub crater began from a drilling platform off the Yucatán Peninsula in Mexico. The crater was formed some 66 million years ago when a large asteroid struck Earth and probably caused the extinction of the dinosaurs. Now researchers believe they have achieved one of the key goals of the drilling: reaching the peak ring, a circular ridge of rock located inside the crater rim. The peak ring would have formed just minutes after impact, when granite bedrock became liquefied and rose up in a column some 10 km high before collapsing back into the crater. Although peak rings have been seen on the Moon, Mars, and Mercury, none has ever been sampled on Earth before. By analyzing core samples from as deep as 1500 meters, scientists hope to better understand how impact craters form and to discover signs of ancient microbial life that may have appeared after the impact.

Nearby small star has three planets in its habitable region

3 May 2016

Atlantic: An exoplanet is commonly found by the telltale dimming of the light of a star as the planet passes in front of it. Earth-sized planets orbiting bright, hot stars like the Sun are nearly impossible to detect, however, because they are so small they don't block much of the star's brightness. For that reason, Michaël Gillon of the University of Liège in Belgium decided to look for planets in orbit around the smallest, dimmest stars. Most theories of planetary formation suggest that such stars should not have enough material around them to form planets, but Gillon argued that the theories are based on very few observations. Using the Transiting Planets and Planetesimals Small Telescope (TRAPPIST) located in Chile, Gillon and his colleagues have identified an ultracool red dwarf only 40 light-years away and orbited by three planets. Subsequent observations from TRAPPIST and other observatories have revealed that all three are Earth-sized and are located in the habitable zone—the region around a star where liquid water may exist. Because of the star's small size and dimness, its habitable zone is much closer to it than the Sun's habitable zone is to the Sun. The closest two planets orbit the star every 1.5 days and 2.4 days.

Super El Niño fueled by failed 2014 event

3 May 2016
Science News: Last year saw the emergence of one of the three strongest El Niño events ever. Heavy rainfall in California, massive coral bleaching in the oceans, and a global heat wave that made 2015 the hottest year on record have been just a few of its effects. But the 2015 event would not have been possible without the failed El Niño from the year before, according to a study published in Geophysical Research Letters. Michael McPhaden and Aaron Levine of the National Oceanic and Atmospheric Administration looked at decades of El Niño data and ran computer simulations. They found that although the 2015 El Niño would have had just a 27% chance of forming, remnant heat in the Pacific Ocean left over from the 2014 nonevent increased the odds to 40%. Strong winds that kicked in sealed the deal. “Strong El Niños require strong winds, not just warm water,” said Levine.

Trusting your gut is the greatest gift you can give yourself

3 May 2016
The best career decisions are made when intuition overrules your brain.

First federal grant awarded to relocate climate change refugees in the US

3 May 2016
New York Times: In January a small community in the US received a federal grant of $48 million to help its residents relocate from an island in Louisiana. Their home, Isle de Jean Charles, has been shrinking over the past half century and is now less than 10% of its original size. Because of rising sea levels due to climate change, the island floods frequently and the bridge connecting it with the mainland is often impassable. Most of the residents are Native American and have lived there for generations. Although some of the roughly 60 residents are happy to leave, many are determined to stay. The resettlement plan, the first of its kind in the world, is only just getting under way and faces any number of obstacles. Yet the residents of Isle de Jean Charles represent just a handful of the estimated 50 million to 200 million people that are expected to be displaced all over the world by 2050 because of climate change. As such, the plan may serve as a global model for the growing wave of refugees who will be forced to flee their homes not for political reasons but for environmental ones.

LIGO team receives $3 million Special Breakthrough Prize

3 May 2016
Guardian: Earlier today, the Special Breakthrough Prize in Fundamental Physics was awarded to the Laser Interferometer Gravitational-Wave Observatory (LIGO) project. Led by Kip Thorne and Ronald Drever of Caltech and Rainer Weiss of MIT, the 1012 researchers and engineers at LIGO announced the first direct detection of gravitational waves in February. The Special Breakthrough Prize is a $3 million award given by the Breakthrough Prize Foundation, which was established by Russian billionaire Yuri Milner in 2012 and is supported by numerous Silicon Valley entrepreneurs to help raise the public profile of scientists. Thorne, Drever, and Weiss will evenly share $1 million of the prize; the rest of the LIGO team will split the remaining $2 million.

Different kinds of knowledge tied to concern about climate change

2 May 2016

Ars Technica: Several past experiments have found that increasing people's knowledge of climate change doesn't necessarily raise their concern about the issue. However, a new paper argues that because those studies treated "knowledge about climate change" as a monolithic concept, they don't necessarily reflect reality. The researchers separated knowledge into three categories: physical knowledge, causes knowledge, and consequences knowledge. Physical knowledge includes understanding concepts such as how carbon dioxide is produced; causes knowledge includes comprehending the effect humans have had on climate change; and consequences knowledge includes grasping the predicted global and local effects of climate change. In a survey of 2495 people in six countries—the US, Canada, China, Germany, Switzerland, and the UK—participants were asked their level of concern about climate change; then they were given questions that tested the three categories of knowledge. Researchers found that although greater physical knowledge correlated with lower concern, greater causes knowledge correlated with greater concern. Greater consequences knowledge also correlated with greater concern, except in Canada and China. Although the new questionnaire has limitations, it provides groundwork for future surveys on the topic.

Second ExoMars mission postponed until 2020

2 May 2016

Sputnik International: Less than two months after the launch of the first part of ExoMars, the Russian space agency Roscosmos announced that the launch of the second component will be delayed by two years, until 2020. ExoMars is a joint mission of Roscosmos and the European Space Agency. The first part of the mission, which will reach Mars orbit in October, includes an orbiter and a lander for studying the Martian atmosphere. Part two includes a rover that will drill into the Martian surface to search for life and perform geochemistry research. According to the team running the rover mission, the decision to postpone the second launch was made because of problems with the contractors and delays in production of the mission's scientific equipment.

Pages