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Updated: 7 hours 13 min ago

Micromotors swim toward and away from the light

17 October 2016
UV radiation spurs a redox reaction that propels micro-sized swimmers in a predetermined direction.

China sends two astronauts on country's longest space mission

17 October 2016

New York Times: Early Monday morning local time, China's space agency launched two astronauts aboard the Shenzhou-11 spacecraft on a mission to dock with the Tiangong-2 space lab, which the agency put into orbit last month. The astronauts are scheduled to spend 30 days aboard the orbital lab, which will more than double the duration of the previous longest mission by a Chinese astronaut. The mission is the sixth crewed mission by China. Aboard Tiangong-2, astronauts Jing Haipeng and Chen Dong will test computers and station equipment and conduct other experiments. China hopes to launch a longer-lived station, Tianhe-1, in 2018.

Universe is home to about 2 trillion galaxies, study says

14 October 2016
Science News: The estimated number of galaxies that exist or existed at one time in the observable universe just jumped about 10-fold. So say Christopher Conselice of the University of Nottingham and his colleagues, who have performed the first detailed census of galaxies in the cosmos. The researchers used a combination of ground- and space-based telescopes to look at a particular volume of the universe to see how it has evolved over time. Although perhaps as many as 2 trillion galaxies existed at one time, the researchers say, many of them have since collided and merged to create larger ones. Nevertheless, there are hordes of relatively tiny galaxies waiting to be discovered that can’t be imaged with current technology.

Former employees sue Arecibo Observatory for discrimination

14 October 2016

Nature: Two former employees at the Arecibo Observatory in Puerto Rico have filed a lawsuit after a US Equal Employment Opportunity Commission (EEOC) investigation determined that they were discriminated against and wrongfully terminated. In November 2015 Elizabeth Sternke informed the Universities Space Research Association (USRA), which oversees Arecibo, that she intended to file a complaint with the EEOC. Soon after, her contract job was terminated early. Subsequently, James Richardson, Sternke's husband and fellow USRA employee, filed his own EEOC complaint. In April 2016 the USRA terminated his position as well. The EEOC investigation found that both Sternke and Richardson had been terminated in retaliation for their complaints. On 4 October the couple filed suit against the USRA and Arecibo's deputy director Joan Schmelz for $2 million in back pay and damages. According to the EEOC, when Schmelz began working at Arecibo, she intentionally sidelined Richardson in favor of younger employees and "marginalized and ostracized" both Richardson and Sternke. Additionally, the USRA altered the job description of a position that Richardson was applying for and subsequently appointed a much younger staff member to fill it.

What was it like to get a PhD in the 1840s?

14 October 2016
The rare step of pursuing a science doctorate required not only hard work and ingenuity but also fluency in German, as scientific luminaries John Tyndall and Edward Frankland discovered.

How to detect oil spills under sea ice

13 October 2016
Experiments in a tank of icy seawater demonstrate the promise of an acoustic approach.

Moon continues to be hammered by meteorites

13 October 2016
Nature: Although most of the craters on the Moon’s surface formed millions of years ago, at least 222 new ones have appeared since 2009. The freshly formed depressions, which were identified by comparing images taken by NASA’s Lunar Reconnaissance Orbiter with those taken decades ago by Apollo astronauts, are distributed across the lunar surface and range in size between 2 m and 43 m in diameter. Because the number of fresh craters is much larger than scientists had expected, researchers may need to rethink estimates of the lunar surface’s age and the design of any future lunar installations.

Lessons from the Lindau Nobel Laureate Meetings

12 October 2016
The annual gathering of brilliant minds highlights the importance of networking for career advancement.

Obama affirms public–private partnership to reach Mars

12 October 2016

BBC: On 11 October CNN published an opinion piece written by President Obama in which he expanded on his previously stated goal of sending crewed missions to Mars by the 2030s. To achieve that goal, Obama wants to continue the partnership between NASA and private spaceflight companies in developing rockets and other technology. NASA already has a close relationship with companies such as SpaceX, which has been resupplying the International Space Station. Just a few weeks ago, SpaceX founder Elon Musk revealed his own ambitious plan to establish a permanent settlement on Mars.

Private consortium plans telescope to find planets in Alpha Centauri

12 October 2016

New York Times: On 11 October a consortium of nonprofits announced a plan to build a half-meter space telescope to look for potentially habitable planets in the Alpha Centauri system. The data from the telescope would allow astronomers to closely analyze any planets found and potentially determine atmospheric composition. Alpha Centauri is a binary system that is located just 4.37 light-years away. Only the star Proxima Centauri, which is now known to host an Earth-sized planet in its habitable zone, is closer. However, the Alpha Centauri stars are much more Sun-like than Proxima Centauri. Jon Morse of the BoldlyGo Institute, one of the organizations leading the consortium, says that the telescope would likely cost between $25 million and $50 million, about one-third the price of a comparable NASA project. The plan is to raise funds through major donations, though the group may also turn to crowdsourcing.

Climate change threatens long-frozen Inuit artifacts in Arctic

11 October 2016
Scientific American: For thousands of years, delicate ivory carvings, wood bows, leather goods, and even mummies from ancient Inuit peoples have lain frozen in the Arctic permafrost. However, as global temperatures warm because of climate change, the permafrost is melting and sea levels are rising. As a result, archaeologists are racing to try to recover those artifacts before they are exposed to the elements or washed out to sea. Anne Jensen, a senior scientist at Ukpeavik Iñupiat Corporation, says that because of the quickly changing climate and limited financial resources, she and her colleagues are being forced to identify the sites with the most potential and salvage what they can.

Montreal Protocol amendment would ban HFCs

11 October 2016
Nature: At the 28th Meeting of the Parties to the Montreal Protocol this week, participants are discussing an amendment that would ban hydrofluorocarbons (HFCs), greenhouse gases that also attack the ozone layer. The most common HFC, the refrigerant HFC-134a, has 1430 times as much warming potential as carbon dioxide over a span of 100 years. Stopping the production of HFCs and gradually cutting back on their use would help not only to protect the ozone layer but also to achieve the goal of the Paris climate treaty to ameliorate global warming. Their ban would prevent the equivalent of 100 billion to 200 billion tons of CO2 being released into the atmosphere by 2050 and could avert about half a degree Celsius of warming by the end of the century.

Media commentators continue protesting: only two women physics Nobel laureates in 115 years

10 October 2016
Statistical analyst Nate Silver calls the typical winner of a Nobel Prize in Physics a “white guy who wears glasses.”

New transistor created with a 1 nm gate

10 October 2016

IEEE Spectrum: Current state-of-the-art commercially available silicon transistors have 20 nm gates; the theoretical minimum for silicon transistors is 5 nm. Some researchers view that 5 nm threshold as the point at which Moore's law, which describes the doubling of the density of transistors on computer chips, will break down. Using molybdenum disulfide and carbon nanotubes, Ali Javey of Lawrence Berkeley National Laboratory and his colleagues have now created a transistor with a gate that is just 1 nm across. Javey is quick to caution that their transistor is far from being commercializable. But simply showing that it is possible for transistors to have gates below the 5 nm mark leaves the door open for the continuation of Moore's law.

A pulsar's changing magnetic field

10 October 2016
The steady decay of the magnetic field at a neutron star's poles shows up in the shifts of an x-ray absorption line.

NASA reconsiders its role in Mars exploration

7 October 2016

Nature: As more countries and commercial companies plan missions to Mars, NASA has begun to rethink its approach to studying the Red Planet. In the past, individual teams of scientists have proposed, built, and operated the scientific instruments that NASA launches into space. However, NASA's current Mars spacecraft are aging and it has just one new one scheduled to launch in 2020. Meanwhile, the European Space Agency, China, and the United Arab Emirates each plan to launch a rover or orbiter to Mars by 2020. And SpaceX could start sending its Red Dragon landers as early as 2018. As NASA's influence in space wanes, researchers may need to start applying for time to use scientific instruments already in place, much as astronomers do to use large telescopes. “The era that we all know and love and embrace is really coming to an end,” said Jim Watzin, head of NASA’s Mars exploration program, at a recent Mars advisory group meeting.

Hurricane Matthew has not behaved as expected

7 October 2016

The Verge: When Hurricane Matthew first became a tropical storm on 28 September, it was not expected to become a major hurricane. However, it quickly turned into one, and by the time it hit several Caribbean islands, it had become a category 4 storm, the second-highest hurricane classification category. Hurricanes in the Atlantic are driven by warm winds traveling west from Africa and passing over warm ocean. The air lifts water vapor into the atmosphere, which lowers air pressure and creates more winds that feed into the cycle until a large storm gathers. Hurricane Matthew formed in an area where high-altitude winds were expected to prevent the storm from exceeding a category 3. Also, the storm did not lose as much energy as expected as it passed over islands in the Caribbean, which is why it remained a category 4 storm as it approached the US coast yesterday.

The diurnal cycle: A bridge between weather and climate

7 October 2016
Our complete understanding of climate and its evolution will require mastery of the 24-hour weather cycle.

Paris climate accord set to enter into force

6 October 2016
Washington Post: For the Paris climate treaty to enter into force, at least 55 countries representing 55% of global greenhouse gas emissions needed to ratify it. That threshold was reached on 5 October with the European Parliament’s vote to join the agreement. “Today is a historic day in the fight to protect our planet for future generations,” said President Obama in an announcement. However, he added that even if every one of the agreement’s targets is met, it will probably be impossible to meet the goal of holding the global average temperature increase to below 2 °C above preindustrial levels. Nevertheless, the agreement should help avert some of the worst climate impacts and spur new investment in renewable energy and other technologies.