Physics Today’s online staff summarize the most important and interesting news about science from the world's top media outlets.
The Independent: Although dark matter can't be seen, its existence is inferred from its gravitational effects on visible matter. According to models created by Gary Prézeau of NASA's Jet Propulsion Laboratory and his colleagues, unlike regular matter, dark matter can pass through planets, and as it does, it gets squeezed into networks of "ultradense filaments." Those filaments are hair-like, with densely concentrated roots and thinner ends that extend away from the planets. Prézeau says that modeling the dark matter could provide clues about where to look for it. To maximize the chance of detecting it, he proposes sending probes into orbit around other, more massive planets, such as Jupiter, where the network of such dark-matter hairs is likely to be denser.
Ars Technica: A wide range of animals use Earth's magnetic fields to migrate every year, but the mechanism by which they detect those fields has been unclear. Now Chinese researchers have identified a protein in the Drosophila fruit-fly genome that binds to iron, which can detect polarity. Called the Drosophila magnetoreceptor protein, dMagR is found inside cells that have light-sensing proteins called cryptochromes, used by birds to identify magnetic field lines. The resulting complex is capable of detecting the polarity, intensity, and inclination of Earth's magnetic field and has an inherent magnetic moment. The researchers also found the same complex in humans as well as in other animals, such as pigeons and mole rats.
Ars Technica: This morning, Blue Origin announced that yesterday it launched its New Shepard rocket to an altitude of 100.5 km and returned it safely to the launch site. It is the first rocket to achieve this task. The ability to reuse hardware could cut the costs of access to space or high-altitude flight substantially. Space X has been working on a similar technique for the first stage of its Falcon 9 rocket, but has had only limited success. Blue Origin's New Shepard combines a booster with a pressurized crew capsule, and its video of the launch suggests that the company intends to use New Shepard for space tourism: Passengers riding in the crew capsule would be lifted into space for a brief period of weightlessness, then the capsule would deploy a parachute before returning to Earth.
New Scientist: Maximizing the amount of material that can be included in space launch cargos is a significant task—boxes and other items have already been converted into flat sheets that take up less space in the cargo and can be assembled in orbit. Lynn Rothschild of NASA's Ames Research Center and her colleagues have now gone one step further by taking the plastic sheets out of the equation entirely. They genetically engineered Escherichia coli bacteria to produce polystyrene and P(3HB) plastics. After the plastic is processed into sheets, a black marker is used to draw lines on them; when the sheets are placed under IR light, the dark areas contract and the sheets fold along the lines. The team also experimented with attaching Bacillus spores to cellulose strips that are strategically placed on the plastic. The spores expand and contract based on changes in humidity, causing the plastic to bend. Further work is needed to make the process practical. Intentionally sending E. coli bacteria to space is risky, however, because they could contaminate the food supplies.
Science: This week, at a meeting of the governing council of the multibillion-dollar ITER fusion project, which is under construction in France, new estimates were presented that suggest the project will cost $13 billion and won't begin operations until the late 2020s. That moves the go-live date at least six years later than previously projected, and about a decade later than initially projected. The council also asked that the seven international partners—China, the European Union, India, Japan, Russia, South Korea, and the US—all provide additional funding for the project. However, after the council meeting concluded today, the delegates said that they would all be conducting their own reviews of the new schedule and funding requests before any long-term decision is made. The council did approve the proposed construction schedule for the next two years.
Ars Technica: In a letter sent to US Commerce Secretary Penny Pritzker, Congressman Lamar Smith (R-TX), chair of the House Science Committee, claims that a National Oceanic and Atmospheric Administration (NOAA) climate study was rushed to publication despite the concerns of several NOAA scientists. Last month, Smith subpoenaed internal communications from NOAA regarding the study, about which he has said that "NOAA employees altered temperature data to get politically correct results and then widely publicized their conclusions as refuting the nearly two-decade pause in climate change we have experienced." In his letter to Pritzker, Smith says the information on which he based his subpoena was provided by whistleblowers. In response to the letter, NOAA says that the study was published in Science after the normal peer-review process and that NOAA has provided all the data, which were already publicly available and should be sufficient to verify the findings.