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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.

SpaceX announces ambitious plans for Mars

28 April 2016
New York Times: Elon Musk, CEO of US aerospace company SpaceX, has announced a plan to land an uncrewed Dragon spacecraft on Mars in about two years. He has previously stated ambitions of sending people to the Red Planet by the mid 2020s. Key to all SpaceX Mars flights is the company's Falcon Heavy rocket, which has yet to launch. SpaceX is teaming up with NASA to share its innovative rocket-engine landing technology for a future Mars mission, according to NASA’s deputy administrator Dava Newman. Even with technological support from NASA, however, SpaceX’s goal of getting to Mars in just two years may prove overly ambitious.

Looking back at a one-off attempt at earthquake control

27 April 2016
Extra Dimensions: Scientists once envisioned triggering minor earthquakes to stave off a devastating one. Today induced quakes endanger millions of Americans.

China cuts plans to build new coal power plants

27 April 2016

New York Times: On 25 April, China's National Development and Reform Commission and its National Energy Administration released guidelines to halt the planned construction of about 200 coal power plants. Plants that are already under construction can be completed, but any project that has yet to be approved or begin construction has been canceled. Although the nixed plants would have added 105 GW to China's power grid, the plants that are currently being constructed will add 190 GW. The announcement is part of China's effort to cut its carbon emissions. China's rapid economic growth has spurred construction of coal plants over the last decade. But during the recent slowdown, many current plants have been operating only 40–50% of the time. China has also begun promoting the construction of wind turbines and solar farms as nonpolluting alternatives to coal power.

New Australian climate science center to open in wake of massive job cuts

27 April 2016
Nature: After announcing that hundreds of climate science jobs are to be cut over the next several years, Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO) has decided to launch a new climate science center. Although the new center will employ some 40 full-time researchers, the number is small compared with the 275 scientists that will probably lose their jobs. The cuts have sparked protests and rallies in several Australian cities, and almost 3000 scientists have signed an open letter expressing their concerns to CSIRO and the government. Once a leader in climate modeling, CSIRO has been struggling to deal with a 16% cut to its budget in 2014.

<em>Hubble</em> spots a moon around dwarf planet Makemake

27 April 2016

National Geographic: Since its discovery in 2005, Makemake has had an odd distinction: It was the only dwarf planet outside of the asteroid belt thought to have no moon. It has now lost that distinction. Alex Parker of the Southwest Research Institute was examining data from two hours of Hubble Space Telescope observations when he saw evidence of an object orbiting the dwarf planet. The data have already revealed that the moon is 160 km in diameter. Further observations of the moon should provide clues as to whether it formed in place around Makemake or was pulled in by the dwarf planet's gravity. More data could also provide information about the moon's mass, which would then allow for more accurate calculations of Makemake's mass and density. The discovery of the moon explains an unusual variation in Makemake's heat signature that did not correlate with any warm, dark areas on Makemake's otherwise brightly reflective, ice-covered surface.

<em>James Webb Space Telescope</em>’s giant mirror assembly unveiled

27 April 2016
BBC: The main feature of the James Webb Space Telescope (JWST)—its 6.5-m-wide gold-coated primary mirror—has been completed and its segment covers removed for the first time. Under construction at NASA’s Goddard Space Flight Center in Maryland, the JWST is to succeed the Hubble Space Telescope as the premier space observatory of the next decade. Its main mirror, which is composed of 18 hexagonal beryllium segments, is about seven times as large as that of the Hubble. To protect the surfaces of the mirror segments from dust and scratches, each had a cover over it. Now that those covers have been removed, the entire structure will be flipped 180 degrees to attach the telescope's scientific instruments. After environmental testing, the JWST will be shipped to NASA’s Johnson Space Center in Texas for final testing. The spacecraft bus and a giant deployable sunshield will then be attached. If all goes to plan, the final assembly will launch in 2018 from the European Spaceport in French Guiana.

Challenges abound for propelling interstellar probes

26 April 2016
Breakthrough Starshot’s proposed laser array for thrusting light sails to Alpha Centauri is costly and unrealistic.

New technique improves image quality of Mars satellite photos

26 April 2016
Gizmodo: Researchers have developed a new technique to boost the resolution of satellite images taken of a planet’s surface. Called Gotcha-PDE-TV (GPT), it combines multiple raw orbital photos of the same spot to enhance the details. Researchers demonstrated the technique with images captured by NASA’s HiRISE camera on board the Mars Reconnaissance Orbiter. Whereas the MRO can usually capture glimpses of objects as small as 25 cm, researchers were able to use the new technique to make out objects as small as 5 cm.

Aging defense satellites jeopardize US climate monitoring ability

26 April 2016
Washington Post: The recent failure of satellite F17, part of the US Defense Meteorological Satellite Program (DMSP), has prompted debate over the US’s ability to continue to collect high-quality climate-related data. Since 1962 the DMSP has been launching satellites that are equipped with passive sensors to detect microwaves emitted by Earth. Because the passive microwave technology is unaffected by cloud cover and darkness, it has proven invaluable in gathering information on such important indicators of climate change as polar sea ice extent plus global precipitation and wind speeds. However, after some 40 years of continuous climate monitoring, the program is now coming to an end. If no new satellites are developed to replace the DMSP’s aging fleet, US researchers will be forced to depend on newer, potentially lower-quality data sources.

Wind farms have little effect on local climate, study says

26 April 2016
BBC: As the number of wind turbines has increased, some people have raised concerns over whether the turbines have adverse effects on local climatic conditions. To find out, a group of researchers has now conducted the first in-depth study by focusing on one of the largest onshore turbine arrays in Scotland, the Black Law Wind Farm. Stephen Mobbs of the University of Leeds and his colleagues installed temperature and humidity sensors across the 18.6 km2 site. Because the turbines had to be shut off for several months for maintenance, the researchers were able to compare conditions when the turbines were operating with those when they were idle. Although the research team did detect a warming effect, it was very small—no more than 0.18 °C. Furthermore, the effect is at ground level and highly localized and so is “not something people should be worried about," said Mobbs.

Incredible light activity photographed above thunderstorms

26 April 2016
New Scientist: Blue jets, red sprites, and glimpses are the names of some of the bright phenomena that occur above clouds during thunderstorms. During a stay aboard the International Space Station, Danish astronaut Andreas Mogensen captured four videos and 160 photos of the weird activity. Although blue jets and sprites have been observed before, the so-called glimpses, or blue blobs of light, were unexpected. The images were presented at the European Geosciences Union meeting last week in Vienna. Also shown were ground-based images of lightning, such as the impressive view of giant upside-down jets of electrostatic discharge fanning out from a monsoon cloud over India. Although lightning is a common occurrence on Earth, its unpredictability has made it hard to study.

“Pushing the greenies to confront their nuclear contradictions”

25 April 2016
Columnists from dissimilar national newspapers offer unusual analyses of emissions-reduction possibilities.

Iron isotope points to recent nearby supernovae

25 April 2016

Los Angeles Times: For the last 17 years, the Cosmic Ray Isotope Spectrometer (CRIS) on NASA's Advanced Composition Explorer spacecraft has been detecting particles approaching Earth. In that time, it has identified more than 30 000 particles of ordinary iron-56 and just 15 particles of radioactive iron-60. But the radioactive isotopes provided enough information for researchers working with CRIS to determine a source. Heavy elements such as iron are created in supernova explosions, but it takes the shock wave of a second supernova to accelerate the atoms and turn them into cosmic rays. The 2.6-million-year half-life of iron-60 allowed researchers to determine that the supernovae that launched the iron particles toward Earth occurred within 2 million years of each other and were relatively nearby. The finding closely matches a separate study that recently suggested a nearby star went supernova roughly 2.3 million years ago.

Lighter, faster, cheaper detection of radiocarbon

25 April 2016
A compact spectroscopic system can measure radiocarbon dioxide concentrations as low as 5 parts per 1015.