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Proxima Centauri, closest star to the Sun, hosts a planet in the habitable zone

24 August 2016

The Kepler space telescope has uncovered a bounty of planets orbiting other stars, but many of those worlds are too distant for in-depth study. Now astronomers have discovered an exoplanet far closer to home—4.22 light-years, to be exact—and it's potentially habitable to boot. Proxima b, reported 24 August in Nature, sits in the liquid-water-friendly habitable zone of the red dwarf Proxima Centauri, the smallest of the three-star Alpha Centauri system and the star nearest to the Sun. From telescope data collected between 2000 and 2008, researchers picked out hints of a signal indicating that the star was wobbling with a velocity of about 1.38 m/s, potentially due to the gravitational tug of an orbiting planet. A dedicated observing run earlier this year by the European Southern Observatory's 3.6 m telescope at La Silla Observatory, Chile, confirmed the planet's presence. The radial velocity measurements reveal that the planet circles the star every 11.2 days, an orbit that puts the planet within Proxima Centauri's habitable zone, and has a mass at least 1.1 times that of Earth's. Although those parameters seem to suggest that Proxima b is both rocky and suitable for life, it's important to note that the planet's diameter, density, and precise mass are unknown. And astronomers are unsure whether life could thrive on red dwarf planets, since they are probably tidally locked and frequently doused in UV and x-ray radiation from stellar flares.

Still, the fact that Earth's nearest stellar neighbor hosts a potentially habitable planet is a discovery worth celebrating. It's a moment astronomers had hoped for ever since the 2012 claim of a planet circling another star in the Alpha Centauri system was thrown in doubt after follow-up observations and analyses. The discovery should also provide a boost for the ambitious interstellar mission Breakthrough Starshot, which aims to launch high-speed miniature probes to the Alpha Centauri system. Although there are many obstacles to overcome for launching such a mission, Proxima b certainly represents an enticing target.

 Digitized Sky Survey 2; Davide De Martin/Mahdi Zamani

Credit: Digitized Sky Survey 2; Davide De Martin/Mahdi Zamani

Here are the best places to learn more about the discovery:

The Washington Post has a nice roundup that emphasizes the limitations in our knowledge of whether Proxima b qualifies as "Earth-like."

At Scientific American, Lee Billings, author of a book on exoplanets, details the discovery and adds helpful context.

A New York Times visualization illustrates the location and orbit of Proxima b along with the radial velocity signal that led to the planet's discovery.

Astronomer Abel Méndez at the University of Puerto Rico at Arecibo's Planetary Habitability Laboratory writes that by one measure Proxima b is the most similar exoplanet to Earth that we know, but that doesn't mean it's the most suitable for life. 

University of Kentucky to sue its student newspaper over sexual harassment case

24 August 2016
BuzzFeed: The University of Kentucky’s student newspaper, the Kentucky Kernel, is facing a legal wrangle with the university over the newspaper’s demands for the release of documents concerning a sexual harassment case involving a university professor. In December James Harwood, an associate professor of entomology, was charged with sexual assault and harassment against two students in his department. Two months later he was allowed to resign his position and avoid a disciplinary hearing. Because of the university’s refusal to provide the Kernel with information about the case, the paper appealed to the state’s attorney general, who ruled in the paper’s favor. Now university president Eli Capilouto says he plans to sue the paper to block the documents’ release.

Pro-Stalin historian becomes Russia's minister of science

24 August 2016
Science: On 19 August, Russian president Vladimir Putin announced the appointment of Olga Vasilyeva to replace Dmitry Livanov as minister of science. Vasilyeva, a historian and expert on the Russian Orthodox Church, had been the head of the religious studies department at the Russian Presidential Academy of National Economy and Public Administration. She says her first goal in office is to examine organizational reforms that Livanov put into place, including the downsizing and reorganization of the Russian Academy of Sciences (RAS). Although some members of the RAS welcome Vasilyeva's appointment, citing her experience in the executive office, others are concerned about her lack of science training and her political views. Vasilyeva is perhaps best known for crediting Joseph Stalin with uniting Russia prior to World War II, and she has said that "the scale of Stalin's repressions has been exaggerated" in several public lectures.

Magnitude 6.2 earthquake strikes central Italy

24 August 2016
BBC: Residents of Accumoli, Italy, and neighboring towns were awakened at 3:36 this morning local time when a magnitude 6.2 earthquake struck. The quake leveled many buildings not only in Accumoli, which was near the epicenter, but also in several neighboring towns, including Amatrice and Pescara del Tronto. At least 73 people have been reported killed, another 150 missing, and hundreds more injured. The area is known for earthquakes because it lies along a major fault line at the juncture of two tectonic plates, the African and Eurasian. In 2009 another town in the Apennines, L’Aquila, suffered a magnitude 6.3 quake, which killed hundreds of people and resulted in several scientists being charged with manslaughter for allegedly failing to adequately warn the public of the danger. Coincidentally, another earthquake, this one magnitude 6.8, struck today near Chauk, Myanmar.

Quantum data locking demonstrated for the first time

23 August 2016

Science News: Proposed 10 years ago, quantum data locking is a method for encrypting information by encoding the entire message, not just the encryption key, in a quantum system. Now Daniel Lum of the University of Rochester in New York and his colleagues have demonstrated the technique for the first time. They defined the state of a photon as their message and then encrypted it by using an equation to scramble the photon's wave function. That ensured the photon would arrive at the intended location on the detector only if the receiver knew the same equation. Although the demonstration is an important step toward secure quantum communication, the technique may not be practical when applied to real-world messages.

Six reasons to get excited about neutrinos

23 August 2016
Extra Dimensions: New results and upcoming experiments offer hope that neutrinos hold the key to expanding the standard model.

First US offshore wind farm prepares to go on line

23 August 2016
New York Times: Off the coast of Rhode Island, five wind turbines that make up the Block Island Wind Farm are being readied for testing in October. Although the project will generate only enough power for about 17 000 homes, it looks to be just the first of many offshore wind ventures as the US pushes for more renewable energy. Some 50 000 turbines are already running on land in the US, where they are cheaper and easier to build. However, ocean wind represents a much steadier, and so far untapped, resource, particularly for the US Northeast, where electrical demand and power rates are high. Unlike Europe, which has been operating offshore wind turbines for more than two decades, the US has been slow to adopt the technology. However, its success abroad may help speed its introduction to the US and bring down the initial costs of installation.

NASA reconnects with Sun-orbiting spacecraft

23 August 2016
New Scientist: After two years of radio silence, NASA has announced that it has successfully reestablished contact with STEREO-B, one of a pair of spacecraft that have been orbiting the Sun since 2006. The mission of the Solar Terrestrial Relations Observatory (STEREO) has been the study of the Sun’s coronal mass ejections. The two spacecraft were so successful initially that the mission got extended several times. In 2014, however, as the spacecraft were about to pass to the far side of the Sun, NASA controllers lost contact with STEREO-B during a planned test of its computer reboot system. It is thought that the probe started spinning out of control, much like what happened to Japan’s Hitomi spacecraft. Although NASA has now managed to make contact with STEREO-B, scientists do not yet know whether the spacecraft will be able to resume normal operations.

John Madey

22 August 2016

Bioluminescent jellyfish proteins used to produce low-energy laser

22 August 2016
New Scientist: To develop better and safer tools for use in biomedical imaging, researchers have worked with both conventional and polariton lasers. Neither has proven satisfactory because the first requires a lot of energy and the second, extremely low temperatures. Now Malte Gather of the University of St. Andrews in the UK and colleagues have overcome both problems by engineering a laser from the green fluorescent proteins found in jellyfish. The researchers placed a thin film of fluorescent protein between two mirrors and got it to fluoresce by shining blue light on it. The result is an organic polariton laser that could be embedded in living tissue and used to map and differentiate among thousands of types of cells.

Higgs discovery prompts proposals for bigger, better particle experiments

22 August 2016
Nature: After the discovery of the Higgs boson in 2012 at the 27-km-circumference Large Hadron Collider (LHC), bigger and better facilities have been proposed to continue the search for new particles. Among them are the 31-km-long International Linear Collider to be built in Japan and two 50 km to 100 km circular colliders, one for protons and the other for electrons and positrons, in China. However, all will cost considerable money to build, and any one project could drain international funding from the others. A less expensive option, proposed by CERN’s director-general Fabiola Gianotti, would be to increase the power of the LHC by installing new superconducting magnets. Rather than turning to powerful colliders, some physicists are hoping novel experiments will lead to the discovery of new physics. The Deep Underground Neutrino Experiment under construction at Fermilab in Batavia, Illinois, will analyze neutrino oscillations and look for new types of neutrinos beyond the currently known three.

Battelle contract renewed to operate Pacific Northwest laboratory

22 August 2016
But DOE wants the contractor to reach out to regional universities and to bring more diversity to the lab’s staff.

US struggles to clean up after 2014 New Mexico nuclear accident

22 August 2016
Los Angeles Times: More than two years ago, a drum of nuclear waste exploded at the Waste Isolation Pilot Plant in Carlsbad, New Mexico. The explosion caused the facility massive long-term damage, which has stalled the shipment of thousands of tons of radioactive waste from US nuclear plants. The accident also led to the discovery of some two dozen safety lapses that had cropped up over 15 years of operation. The Department of Energy, which manages the site, has been slow to clean up but hopes to reopen the site for limited use by the end of the year. To meet its contractual obligations to dispose of waste from US nuclear weapons research and production, DOE has said the facility may have to stay open longer than planned or increase the amount of waste it accepts each year.

NASA sets ambitious budget goals for Space Launch System

22 August 2016
Ars Technica: Since the end of the space shuttle era, NASA has been developing its next-generation launch vehicle. Called the Space Launch System, it is set to be the most powerful rocket ever built. It could also be the most expensive. Keeping costs down is “going to take some different thinking and maybe a little bit more risk taking,” said Bill Hill, NASA deputy associate administrator for exploration systems development, in an interview with Ars Technica. The goal, he says, is to keep production and operations costs to $2 billion or less, or roughly half NASA’s annual budget, so that the other half could be used to fund human missions to the Moon or Mars.

Inside droplets that won’t freeze are crystals that won’t melt

22 August 2016
The strange nanoparticles are yet more evidence that in materials science, small is different.

UK looks at small nuclear reactors as alternative to big plants

19 August 2016

Reuters: The $24 billion project to build a nuclear power plant at Hinkley Point in the UK has inspired several companies and government agencies to begin exploring the potential usefulness of small modular reactors (SMRs). Those scaled-down versions of reactors comprise a series of smaller parts, or modules, that can be made in factories, easily transported to a construction site, and assembled in just 6 to 12 months. Many companies envision using multiple SMRs in the place of a single large reactor because they could produce nearly as much electricity at a fraction of the cost. The UK's National Nuclear Laboratory estimates that by 2035, up to 7 GW of electricity—more than twice the planned capacity of the Hinkley Point power plant—could be generated by SMRs.

Australian shared solar power network will utilize blockchain

19 August 2016

New Scientist: A blockchain is a method of securing data by encrypting batches of transactions made within a system and linking them into a chain that is then stored on all the computers in a network. It is most commonly used for cryptocurrencies such as bitcoin. Now residents in a community in Australia will use a blockchain to share the electricity they generate from their home solar panels. In the initial test run, 20 households in the community will be equipped with a Raspberry Pi computer system to track their energy use. The system will record transactions as residents sell their extra electricity to each other, though no energy will actually be traded for the first two months. Assuming the test is successful, PowerLedger, the company behind the system, plans to deploy larger networks in Perth and Victoria next year.

Satellite data used to pinpoint the poorest areas of the world

19 August 2016
BBC: Identifying the poorest of Earth’s residents can be difficult for various reasons, including their remoteness or local political instabilities. Although satellites have been used to map poverty by looking for the most sparsely illuminated areas, that criterion has not proven definitive. Now a team from Stanford University has combined those nighttime maps with high-resolution daylight images to look for indications of different levels of economic well-being, such as the number of paved roads compared with unpaved ones and the presence of metal roofs on buildings. Sophisticated computer software then categorizes the various indicators and looks for details and patterns that are “predictive of poverty,” says Marshall Burke, one of the team members. To verify the computer model’s accuracy, the researchers compared the results with household survey data.

Climate change forces Alaskan village to move

19 August 2016
NPR: Although they have considered relocating since 1976, the residents of Shishmaref, Alaska, have now officially voted 94–78 to move. The reason is coastal erosion due to climate change. Shishmaref, an Inupiat native village, is located on a barrier island in the Chukchi Sea, north of the Bering Strait. For decades, storm surges have been damaging homes and other structures, and rising waters and melting permafrost have been eating away at the island’s land mass. Within the next 30 years, the village will be completely underwater, says resident Esau Sinnok. The plan is to move the entire village to the mainland so that the community can remain together. However, the costs of moving an entire village could ultimately prove to be prohibitive, and some of the residents, particularly members of the older generation, do not wish to move.

Meltwater lakes growing in size and number in East Antarctica

18 August 2016
Washington Post: Based on satellite imagery, researchers have observed a growing number of meltwater lakes forming on top of the Langhovde Glacier in East Antarctica, Earth’s largest ice mass. Stewart Jamieson of Durham University in the UK, coauthor of a study led by fellow Durham researcher Emily Langley, said the number, area, and depth of the lakes appear to correlate with warmer temperatures in the region. The effect is reminiscent of what has been happening in Greenland, Earth's fastest-melting ice mass. The researchers say the melting could be weakening the ice shelf, which could contribute to global sea-level rise. Although the lakes are not big enough yet to pose a problem, Jamieson said, that could change if warming continues.

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