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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.

Sounding out the qin

2 May 2016
Tests reveal the acoustic properties of an exalted musical instrument.

Tailless comet could provide clues to solar system’s formation

2 May 2016
Reuters: Discovered by the Panoramic Survey Telescope and Rapid Response System, C/2014 S3 is the first comet ever observed to have no tail. Most comets, which form in the distant, frigid parts of the solar system, stream a bright trail of vaporized ice as they approach the heat of the Sun. Despite originating in the Oort cloud, the same region of space as typical tailed comets, C/2014 S3 lacks the ice and other frozen compounds those comets contain. Instead, the comet appears to be made of rocky materials normally found nearer Earth. In a study published in Science Advances, Karen Meech of the University of Hawaii and her colleagues say the comet may be made of material formed in the inner solar system and ejected billions of years ago. If so, it could provide clues to the solar system’s formation and whether the planets migrated significantly before settling into their present configuration.

Coral reef off Florida damaged by dredging, says study

2 May 2016
New York Times: Recent damage to the only coral reef in the continental US, located off South Florida, has become the subject of controversy following a large-scale dredging project undertaken by the US Army Corps of Engineers. Although the corps blamed white plague disease, a virus that bleaches and kills coral, a study by the National Oceanic and Atmospheric Administration says instead that the damage was caused by the dredging, which stirred up plumes of sediment that then buried and suffocated the reef sections nearest the dredging site. The project was carried out to deepen the port of Miami to accommodate modern freighters. Even before the dredging began, as much as 80–90% of the reef had already died or been damaged because of other factors, including fluctuating ocean temperatures, acidification, sewage, pollution, and white plague. Besides being important to marine biodiversity, coral reefs help protect the shoreline from hurricane damage. The issue is regaining momentum as Fort Lauderdale seeks final approval of the dredging of its own port, one of the largest in the US.

ITER costs are pinned down, with caveats

29 April 2016
External review of international fusion project comes as Department of Energy prepares to make recommendations to Congress on whether US should remain involved.

Sci-Hub use continues to grow

29 April 2016
Science: Created in 2011 by Alexandra Elbakyan, at the time a graduate student in Kazakhstan, Sci-Hub is a database of more than 50 million scientific papers and articles, many of which are otherwise only accessible with subscriptions to journals. Science's John Bohannon obtained six months' worth of data and analytics from Elbakyan to determine who is using Sci-Hub—and discovered it's basically everyone. In the six-month period, the site delivered some 28 million documents. About 4.4 million requests came from users in China, 3.4 million from India, and 2.6 million from Iran. Russia came in fourth, and the US fifth. The requests reveal that it's not only countries that are under international sanctions or experiencing economic difficulties that drive Sci-Hub's traffic. The 34 members of the Organisation for Economic Co-operation and Development, some of the wealthiest nations in the world, account for a quarter of the site's traffic.

Report supports ITER's delayed schedule but not its ballooning budget

29 April 2016

Science: Last year, the council of representatives for the member states supporting the ITER fusion energy project in southern France created an independent panel to review the project's revised budget and schedule. Since construction began in 2013, ITER has been plagued with cost overruns and delays. In its report presented on 27 April, the panel said that although the revised startup date of 2025 is reasonable, the additional €4.6 billion ($5.3 billion) that will be needed to complete the project is not. In response, the council has instructed the ITER management team to find a way to continue with construction without exceeding the financial constraints. Projected costs for ITER, which was originally scheduled to be completed this year, have reached roughly $20 billion. The ballooning costs and sliding completion dates have caused several of the member states to consider cutting their support.

Ancient Japanese and Finnish ice records yield insights into climate change

29 April 2016
National Geographic: Ice observations made in Japan and Finland over the past several centuries are helping modern climate scientists better track climate change. Since at least 1443, Shinto priests have been recording the formation of a distinctive ice ridge on Lake Suwa in the Kino Mountains of central Japan. In Finland, a merchant named Olof Ahlbom started recording the spring ice breakup on the Torne River in 1693, and those observations have been continued by others ever since. By studying the seasonal patterns of ice formation in two such geographically distinct areas over hundreds of years, John Magnuson of the University of Wisconsin–Madison and colleagues have been able to gather important climate data, particularly from before the start of the Industrial Revolution. They note that Suwa has been freezing over progressively later each year and that Torne has been thawing progressively earlier. Also, both areas have been experiencing an increase in the number of extreme warm years. If atmospheric carbon dioxide concentrations and air temperatures continue to rise, the researchers say, Lake Suwa and many other lakes and rivers around the world will fail to freeze over at all.

Japanese satellite <em>Hitomi</em> suffers permanent failure

29 April 2016
Nature: On 28 April the Japan Aerospace Exploration Agency announced that it had lost control over its flagship astronomical satellite Hitomi. Despite a successful launch on 17 February, the satellite began experiencing problems within the first few weeks. The source of the difficulty has been traced to its star tracker system, one of several systems on board designed to orient the satellite in space. The star tracker was found to malfunction every time the satellite passed through a certain area over Earth called the South Atlantic Anomaly, where the belts of radiation encircling the planet dip closest to its surface and thus expose satellites to higher-than-normal radiation levels. On 26 March, while Hitomi was passing through that area, a glitch with the star tracker initiated a series of failures with the satellite’s gyroscopes. Hitomi spun out of control, and its solar panels and other components broke off. Although the loss of Hitomi represents a significant blow for x-ray astronomy, before it failed scientists were able to make one important astronomical observation, which could yield enough data for a series of papers.

William H. Holt

28 April 2016

Researchers assemble an all-nanocrystal transistor

28 April 2016
Their recipe may lead to cost-effective manufacture of flexible electronics.

Historical observations supplement modern theories on ancient supernova

28 April 2016
National Geographic: Two recently discovered texts by ancient Arab scholars are providing new information on the brightest known supernova, SN 1006. In AD 1006 a transient celestial object was seen in the night sky. It blazed brightly over a period of several months and then disappeared. The event was recorded by early stargazers in Asia, the Middle East, and Europe. Now Ralph Neuhäuser of the Friedrich Schiller University Jena in Germany and his colleagues have discovered mention of SN 1006 in works by Persian scientist Ibn Sina and historian al-Yamani of Yemen. Sina’s account emphasizes the color evolution of the supernova event, which he says began as a faint greenish yellow, twinkled vigorously during peak brightness, then turned white before ultimately vanishing. The account by al-Yamani suggests that the supernova manifested itself earlier than many modern astronomers had thought, in mid April rather than at the end of the month. Although Sina’s description has been criticized because of the subjectivity of brightness observations, al-Yamani’s fixing of the date agrees with Neuhäuser’s own work.

Microsoft begins testing DNA for data storage

28 April 2016

Ars Technica: At nearly 1 zettabyte (1 billion terabytes) per gram, DNA has a significantly higher data storage density than conventional storage systems. And the molecule is extremely robust: Fragments that are thousands of years old have been sequenced. The successful encoding of binary data as DNA base pairs in 2010 opened up the potential for using the molecule for long-term data storage. Now Microsoft is purchasing 10 million strands of DNA from Twist Bioscience, a biotech startup that has developed a machine for producing custom strings of DNA. Twist has been producing DNA for biology research labs. Currently, the price is roughly $0.10 per base, but Twist hopes to reduce that cost to $0.02. Reading the data involves traditional genetic sequencing, which costs about $1000 per genome. In initial tests with Twist, Microsoft says it has succeeded in retrieving all the data that had been encoded in the DNA. The price of storage means that commercial use is still a ways off, but improvements in both creating and sequencing DNA molecules will likely lead to lower costs.

Appropriations changes force cut to NASA's Mars landing technology

28 April 2016
Space News: The 2016 appropriations bill approved by Congress in December is a mixed bag for NASA's space technology budget. The bill comes with an increase of $90 million over 2015 to $686.5 million. But Congress also moved the RESTORE-L satellite servicing project from NASA's space operations budget to the space technology budget and allocated $133 million to the project. James Reuter, NASA's deputy associate administrator for space technology, says the move meant that NASA had to cut $40 million from other programs. The major loser is the Low Density Supersonic Decelerator (LDSD), which was to receive $20 million in 2016. LDSD is a project to study inflatable decelerators and advanced parachutes as methods for slowing down spacecraft to land on planetary bodies with very thin atmospheres, such as Mars. So far LDSD researchers have performed two unsuccessful tests, and NASA has not decided whether to go forward with a third. NASA had planned to evaluate the project's options, but the budget cut will severely limit the agency's ability to do so.

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