Science: Space weather is expected to become more severe over the next few decades, partly as the Sun’s activity changes. Frequent flyers and astronauts will face greater radiation hazards as a result.
In times of higher activity, the Sun emits solar energetic particles (SEPs) more consistently, but at the same time generates a strong magnetic field that shields Earth against galactic cosmic rays (GCRs). Right now, the Sun has been declining to a new minimum, from a peak in about 1920. At this minimum more GCRs will reach Earth. However, although there are fewer SEP events, those that do occur are more intense. Frequent fliers are at increased risk because the thin air at high altitudes doesn’t give much protection from space weather. Astronauts, especially those traveling to the Moon or beyond, would face more potential problems; expected radiation doses from a roundtrip to Mars would increase at least twofold. This may limit space travel to Mars until 2050 at the earliest.
Daily Archives: September 26, 2011
Becoming invisible to magnetic fields
BBC: While researchers have been making advances toward developing a Harry Potter–style invisibility cloak containing metamaterials that guide light waves around the cloak’s wearer, a group in Spain has designed a “cloak” that renders the wearer invisible to magnetic fields, according to a paper published in the New Journal of Physics. Because light and magnetism are two facets of the same physical force, many of the same principles apply. Thus Alvaro Sanchez and coworkers at the Autonomous University of Barcelona have developed an antimagnet, which uses an inner cloak of superconducting material, surrounded by layers of metamaterials whose response to the magnetic field varies in a prescribed way through the thickness of the cloak, writes Jason Palmer for the BBC. Their device could have many uses, including protective shielding of pacemaker wearers during MRI scans.
World’s first 3D printed car
Daily Mail: Three-dimensional printing has taken off in recent years, with the creation of such diverse objects as flutes and human tissue and organs. Now a Canadian company called KOR EcoLogic has designed and printed its first automobile. The Urbee is “built” from layer upon layer of an ultrathin composite material that is slowly fused into a solid. It has three wheels, two seats, and a hybrid gas/electric engine. The company claims the car is among the greenest ever made: It uses one-eighth the energy of a similar-sized vehicle and can get 200 miles to the gallon on the highway. It will be some time, however, before the Urbee can be mass produced and available to consumers.
Texas holds firm on physics closures
Nature: Texas remains determined to phase out “low-performing” physics programs at state-funded universities if they fail to graduate at least 25 students every five years. This could affect nearly half of the 24 undergraduate physics programs in the state. The plans are consistent with the business-based approach advocated by Texas governor Rick Perry; they are also being considered by Florida governor Rick Scott as a way to reduce higher-education budgets in his state. While other undergraduate programs in Texas will be subject to the same metrics, physics programs are more at risk because they tend to enroll fewer students to begin with. Many smaller programs that don’t meet the metric are in areas with predominantly African American, Hispanic, or other disadvantaged populations. Cutting programs in those areas could deny minority students access to science-related education. About 35% of undergraduate degrees in physics awarded in the US go to students in programs that don’t meet the Texas Higher Education Coordinating Board requirements.