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Ford's Solar-Powered Hybrid Car Displays Sun-Tracking Technology

Ford's new concept for solar-powered hybrid car can run for 21 electric-only miles on a day's worth of sunlight. That possibility comes courtesy of sun-tracking software that works in combination with a concentrator lens to focus the sunlight falling on the car's rooftop solar panels.

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Google Glass Gets Wink Control for Taking Pictures

Taking a picture on Google's smart glasses is now as easy as winking. The newly official feature allows Google Glass wearers to capture images without resorting to the drudgery of pressing a camera button above the right eye or speaking the sentence "OK glass, take a picture."

The official Google blog post imagines that winking control will eventually enable instantaneous shopping, instant payment of taxi cab fares, hands-free summoning of cooking recipe instructions, and much more. But the initial feature of winking for photos will likely prove satisfying for many wearers, even if it's potentially confusing for their friends and family.

"Whether it's capturing an amazing sunset on an evening walk, or photographing your receipt for the lunch you'll need to expense, you can now stay in the moment and wink to take a picture instantly," said the Google blog post.

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Gaia, ESA's "Phenomenal" Milky Way Mapper, Is Set to Launch

Update (December 19, 2013): Gaia successfully took off at 9:12 GMT. The spacecraft will take several weeks to arrive at the L2 point and will begin routine operations around April 2014.

Gaia, the European Space Agency's long-awaited space observatory, is set to launch on Thursday from the agency's spaceport in Kourou, French Guiana.

The €700 million mission is designed to pin down the three-dimensional positions and velocities of a billion Milky Way stars, which amounts to roughly one out of every 100 stars in the galaxy. 

Gaia is only the second space telescope dedicated to astrometry, the measurement of stellar distances. The first, Hipparcos, launched in 1989. It carried pre-CCD technology and was capable of measuring just one star at a time using a photomultiplier tube. Gaia, in contrast, has a bank of 106 CCDs. Together, they have almost 1 billion pixels and provide half a square meter of sensor area, making it the largest focal plane yet sent to space. 

Like its predecessor, Gaia will gauge distance through parallax, the subtle change in position that occurs when you view an object from two different angles. Think of a pencil held in front of your nose: it shifts position against more distant background objects if you look at it first with one eye and then the other. The farther you hold it from your nose, the smaller this shift.

As I explain in my January article previewing the mission, because parallaxes are very tiny at interstellar distances, Gaia's "eyes" must be very far apart. To get a big enough change in perspective, the spacecraft will observe the same patch of sky first when it's on one side of the sun and then again, half a year later, when it's on the opposite side. After the data's crunched, Gaia's precision will comparable to standing in your backyard and seeing an insect on the surface of the moon.

As an optical observatory, Gaia will have a tough time seeing stars in dustier parts of the galaxy. But a number of the astronomers I spoke with told me they expected Gaia could still have a big impact on the calibration of cosmic distances and the study of Milky Way history and structure, including the distribution of dark matter. Barry F. Madore of the Carnegie Observatories in Pasadena, Calif., who is not affiliated with the mission, was particularly excited about the Gaia's prospects. "It's going to be phenomenal," he told me. "It will change everything."

Illustration: ESA

ESA has put together an animation showing Gaia's path from launch to orbit, including the deployment of the spacecraft's 10-meter-wide sun shield; its trip to the second Lagrange, or L2, point, where it will orbit the sun in tandem with Earth and avoid flying in and out of Earth’s shadow; and the view from its two telescopes.

Launch is set for 9:12:19 GMT (4:12:19 EST). The event will be broadcast live on this site, and ESA plans to post updates on this blog.

Orbiting ‘Magnetism to Light Converter’ Maps Earth’s Magnetic Field

The European Space Agency’s Swarm expedition was launched from the Plesetsk Cosmodrome on 22 November, on a mission to study how the Earth’s magnetic field and ionosphere vary in time and space. It started sending back data four days later.

The mission consists of three identical satellites launched into separate polar orbits that will let them sheathe the Earth in a web of magnetic measurement. Swarm will gauge the direction and strength of the planet’s magnetic field more precisely than ever before, using instruments up to five times as sensitive as those deployed on the Danish Øersted (launched 1999) and German CHAMP (2000) satellites. These measurements will return data on every part of the Earth, from the dynamo at the planet's core to the workings of the ionosphere and magnetosphere. It may even, perhaps, explain more about the magnetic “soft spot” that hovers over the South Atlantic (and might presage one of the periodic reversals in the Earth’s magnetic polarity).

Each Swarm spacecraft looks like an elongated horseshoe crab, with a solar-cell-covered carapace and a rapier of a tail. Once unfolded, the tail is a tubular, 4.3-meter-long, carbon-fiber-reinforced polymer boom. It’s manufactured without any magnetic components, because it is carries some of the most advanced magnetic-field-measurement instruments yet built.

About halfway down the boom is an optical bench that couples a three-axis star-tracking telescope with a Vector Field Magnetometer (VFM)—a highly sensitive device for measuring the intensity and orientation of magnetic lines of flux. Overall, the assembly (devised by researchers at the Danish Technical University) is accurate to within about 0.5 nanotesla (0.5 x 10-9 T) in field strength and 0.1 degrees in satellite attitude. The VFM, which is the satellite’s primary instrument, will measure not only the direction and strength of the surrounding magnetic field, but also plot it against positions confirmed by the three-way star-sight.

At the end of the boom is a new design—the Absolute Scalar Magnetometer, (ASM) built by CEA-Leti (Grenoble, France), with scientific support from the Institut de Physique du Globe de Paris and financing and logistics from the Centre National d’Etudes Spatiales (CNES), the French national space agency.

The ASM’s nominal role is to understudy the VFM, helping to keep the vector instrument calibrated. What it actually offers, say the designers, goes a lot farther. (For a collection of papers on ASM’s design, see this CNES library.)

The device uses low-density helium as its sensor, and exploits the Zeeman effect—the splitting of the element’s emission-spectrum lines in a magnetic field.

To measure this spread, the ASM first applies radio frequency energy to lift electrons from their ground state to a metastable intermediate energy level (actually, one of three levels, since the Earth’s magnetic field splits this level into three levels, depending on the combined spins of the atom and its electrons).

Then a linearly polarized laser beam further pumps electrons to an even higher, though very short-lived, excited state. In one-tenth of a microsecond, the electrons drop back into one of the metastable levels, giving off photons and creating three closely grouped spectral lines (clustering at around 1083 nanometers wavelength in the infrared). The gap between the lines is proportional to the ambient magnetic field.

The instrument incorporates a number of refinements. To maintain accuracy, the designers had to maintain a constant relationship between the stimulating laser beam and the applied magnetic fields. By using a beam that’s polarized linearly rather than (as in previous designs) circularly, the designers were ab keep the system aligned by adjusting the direction of polarization rather than the direction of beam propagation—and it’s much easier to change polarization than to move the laser. In the ASM, non-magnetic piezoelectric motors control the orientations of the RF coils.

The net result is that the Absolute Scalar Magnetometer is about ten times as sensitive as the Vector Field Magnetometer, with a maximum error of less than 65 picotesla (65 x 10-12 T). By comparison, that’s about one millionth of the Earth’s surface magnetic field, which ranges from about 30 to 60 microtesla (30-60 x 10-6 T), and about one one-hundred-millionth the magnetic field strength of a common household refrigerator magnet (5 x 10-3 T). The precision should be better than 1 picotesla, and the noise levels are low, better than 1 pT / (Hz)1/2.

Also, the ASM uses three orthogonal sets of RF coils. The device is able to report how much of the scalar field is projected along each of these axes…so, voila, the scalar magnetometer can also function as a vector magnetometer, although at a lower sampling rate and with reduced accuracy. Among other experiments, the Swarm mission will test whether the understudy ASM might be ready to step out from backstage and take on the starring role of the VFM.

Illustrations: ESA 

Modified 18 Dec. 2013 to include correct launch site at Plesetsk.

Space Station's Cooling System Suffers Partial Shutdown

One of the "Big 14" problems that NASA thought would likely strike the International Space Station has reared its ugly head again. A cooling system malfunction has cut the space station's temperature-regulating capabilities in half, forced the shutdown of some science experiments, and possibly delayed the launch of a private spacecraft resupply mission.

The latest problem affected one of two pumps that circulate ammonia coolant in two cooling loops outside the space station, according to SPACE.com. Those exterior cooling loops radiate excess heat transferred over from internal cooling systems inside the station and also cool the electricity-generating solar panels on the outside of the orbital outpost.

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IRIS Satellite Images Shake up Solar Science

The first images from NASA’s latest solar observing satellite are in, and they show unprecedented detail—and unexpected complexity—in the roiling lower layers of the Sun’s atmosphere. Already, the images have revealed a previously-unseen fibrous inner structure of many solar features, including the familiar earth-size prominences that can erupt into solar flares and the less-well-known, 500-kilometer-wide spicules that jet up into the corona at speeds of 20 km/s.

Although the data has just started to come in, the early results are enough to challenge the current numerical models of solar behavior.

The pictures from the IRIS (Interface Region Imaging Spectrograph) Observatory, launched 27 June this year, capture images that are sharply defined in space, time, and wavelength. The instrument combines an ultraviolet telescope with a high-precision spectrograph. The imager can resolve solar features 250 km in diameter (see the comparison photos below). The spectral data is used to calculate the atmosphere’s temperature and, thanks to Doppler shifts, its detailed motion (to within one kilometer per second).

Photo: NASA
This image compares the Solar Dynamics Observatory (SDO) Atmospheric Imaging Assembly (AIA) at 1600 Angstroms (on left) to the IRIS' Si IV (on right).

The spectrograph can record targeted transition emissions over the range of temperatures from 4500 K to 10 000 000 K, focusing on specific emission lines of magnesium, silicon, carbon, oxygen, and iron, which vary with temperature. The imager also takes pictures—covering an area about 170 arc-seconds (equal to 124 000 km at the sun)—at wavelengths corresponding to a temperature range between 4500 K and 65 000 K. This allows the researchers to separately image the photosphere, chromosphere, interface region, and corona.

Because the spectrograph is fast, IRIS can combine big images with very fine spectra of every 240-km-wide slice of the scene. This reveals the temperature, density, composition, and motion of the solar atmosphere with detail previously unachievable.  (IRIS's design is described in a 2012 IEEE Aerospace Conference paper.)

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Plastic Lasers Starting to Shine

Organic lasers could be tuned to emit a broad range of wavelengths, could be built on sheets of plastic, would be flexible enough to bend, and very inexpensive to make. But while organic LEDs are a big part of the smartphone display market and are making inroads in solid-state lighting and flexible solar cells, the laser remains elusive.

“The OLED display works so well, it would be really nice to have a laser as well,” says Karl Leo, who heads the Institut für Angewandte Photophysik of TU Dresden and the Solar Center at King Abdullah Unhiversity of Science and Technology, Saudi Arabia.  Leo, who spoke at the Fall Meeting of the Materials Research Society (MRS) in Boston last week, says his lab has come up with a possible path toward an electric-powered organic laser by adding some metal to the laser cavity.

Optically pumped organic lasers, which use light from another laser as a power source, already exist. At another MRS session, a German company, Visolas, described an optically pumped organic laser they’re close to commercializing as part of a mobile blood analysis system. But lasers are usually considered viable only when they can run on electricity, and that’s Leo’s goal. The trouble is that such electrical pumping requires a high density of excited charge carriers, on the order of kiloamperes per square centimeter. Such levels are not a problem in an inorganic material, such as gallium arsenide, but the carriers would create additional detrimental absorption and the heat generated could damage the organic materials.

Metal, too, is usually a bad thing to have in a laser cavity, because the metal absorbs photons to such an extent that it kills the lasing effect. Leo’s team built a vertically oriented laser cavity that consists of an organic “active layer” between two mirrors. The mirrors are reflective gratings made from alternating layers of titanium oxide and silicon dioxide. In between the bottom mirror and the active layer they placed stripes of silver, 40 nanometers thick and 1110 nm wide.

Placing the metal grating on top of the reflective grating caused the creation of so-called Tamm plasmon polaritons. Plasmon polaritons are oscillations of electron density that can exist at the interface between metal and other materials and amplify light, so the placement of the metal actually increased the lasing effect. “It’s possible to include a highly conductive metal contact into the cavity,” Leo told the meeting. “If you pump it hard enough, it can lase.”

He says, though, this is only an early step toward an organic laser. Reaching the threshold where the device begins to lase still requires very high currents that wouldn’t be practical in a real device. Therefore, he says, a useful organic laser could still be a decade in the future.

Still, he believes the pursuit is worthwhile. A cheap, broadly tunable laser would certainly be welcomed in optical communications, and it’s likely people will develop other applications, just as they did once inorganic lasers were created. “I’m sure if somebody makes an electric organic laser there will be a use for it,” says Leo.

New Industry Group Hopes Open Source Framework Can Propel the Internet of Things

The days of sitting in your driveway to listen to the end of your favorite song or compelling news broadcast may be over soon. Ditto on worrying about where you put your house keys.

A newly formed industry consortium, the AllSeen Alliance, wants to advance the adoption of the “Internet of things” through an open source framework. The Internet of things is based on the idea that devices and objects can connect to each other for seamless sharing of information and coordinated operations.

In such a connected world, you could turn the car off, open your front door and have the same song or radio show playing in your home. Additionally, when you drive up to your house, the doors could unlock automatically.

The AllSeen Alliance involves leaders in home appliances and computing, including the Linux Foundation, LG Electronics, Panasonic, Qualcomm, Sharp, Cisco, D-Link and others. The software framework comes from a project originally developed by Qualcomm called AllJoyn, which allows products to communicate over Wi-Fi, power line networks, or Ethernet. The alliance members plan to expand the standard and take input from the open source community.

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Spy Games: Spooks Infiltrated Online Games

“Tracking terrorists” may represent the best official excuse ever concocted for U.S. and British spies to play online games at work. But it remains unclear whether such cyber-sleuthing efforts have paid off, according to new revelations from the Snowden documents.

The Guardian, New York Times and ProPublica jointly reported on a U.S. National Security Agency document written in 2008 and titled "Exploiting Terrorist Use of Games & Virtual Environments." The document revealed the NSA's strong interest in extending surveillance of potential terrorists and other intelligence targets to World of WarcraftSecond Life and Microsoft's Xbox Live service—online gaming spaces already being infiltrated by FBI, CIA, and Pentagon spies back in 2008.

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