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NASA Mars Rover Targets Unusual Rock!

NASA Mars Rover Targets Unusual Rock Enroute to First Destination

ScienceDaily (Sep. 19, 2012) — NASA’s Mars rover Curiosity has driven up to a football-size rock that will be the first for the rover’s arm to examine.  Curiosity is about 8 feet (2.5 meters) from the rock. It lies about halfway from the rover’s landing site, Bradbury Landing, to a location called Glenelg. In coming days, the team plans to touch the rock with a spectrometer to determine its elemental composition and use an arm-mounted camera to take close-up photographs.

Both the arm-mounted Alpha Particle X-Ray Spectrometer and the mast-mounted, laser-zapping Chemistry and Camera Instrument will be used for identifying elements in the rock. This will allow cross-checking of the two instruments. The rock has been named “Jake Matijevic.” Jacob Matijevic (mah-TEE-uh-vik) was the surface operations systems chief engineer for Mars Science Laboratory and the project’s Curiosity rover. He passed away Aug. 20, at age 64. Matijevic also was a leading engineer for all of the previous NASA Mars rovers: Sojourner, Spirit and Opportunity. Curiosity now has driven six days in a row. Daily distances range from 72 feet to 121 feet (22 meters to 37 meters). “This robot was built to rove, and the team is really getting a good rhythm of driving day after day when that’s the priority,” said Mars Science Laboratory Project Manager Richard Cook of NASA’s Jet Propulsion Laboratory in Pasadena, Calif. The team plans to choose a rock in the Glenelg area for the rover’s first use of its capability to analyze powder drilled from interiors of rocks. Three types of terrain intersect in the Glenelg area — one lighter-toned and another more cratered than the terrain Curiosity currently is crossing. The light-toned area is of special interest because it retains daytime heat long into the night, suggesting an unusual composition. “As we’re getting closer to the light-toned area, we see thin, dark bands of unknown origin,” said Mars Science Laboratory Project Scientist John Grotzinger of the California Institute of Technology, Pasadena. “The smaller-scale diversity is becoming more evident as we get closer, providing more potential targets for investigation.” Researchers are using Curiosity’s Mast Camera (Mastcam) to find potential targets on the ground. Recent new images from the rover’s camera reveal dark streaks on rocks in the Glenelg area that have increased researchers’ interest in the area. In addition to taking ground images, the camera also has been busy looking upward. On two recent days, Curiosity pointed the Mastcam at the sun and recorded images of Mars’ two moons, Phobos and Deimos, passing in front of the sun from the rover’s point of view. Results of these transit observations are part of a long-term study of changes in the moons’ orbits. NASA’s twin Mars Exploration Rovers, Spirit and Opportunity, which arrived at Mars in 2004, also have observed solar transits by Mars’ moons. Opportunity is doing so again this week. “Phobos is in an orbit very slowly getting closer to Mars, and Deimos is in an orbit very slowly getting farther from Mars,” said Curiosity’s science team co-investigator Mark Lemmon of Texas A&M University, College Station. “These observations help us reduce uncertainty in calculations of the changes.” In Curiosity’s observations of Phobos this week, the time when the edge of the moon began overlapping the disc of the sun was predictable to within a few seconds. Uncertainty in timing is because Mars’ interior structure isn’t fully understood. Phobos causes small changes to the shape of Mars in the same way Earth’s moon raises tides. The changes to Mars’ shape depend on the Martian interior which, in turn, cause Phobos’ orbit to decay. Timing the orbital change more precisely provides information about Mars’ interior structure. During Curiosity’s two-year prime mission, researchers will use the rover’s 10 science instruments to assess whether the selected field site inside Gale Crater ever has offered environmental conditions favorable for microbial life. For more about Curiosity, visit: http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl. You can follow the mission on Facebook and Twitter at: http://www.facebook.com/marscuriosity and http://www.twitter.com/marscuriosity.

 

 

Classical Chaos Occurs In The Quantum World, Scientists Find

Classical Chaos Occurs In The Quantum World, Scientists Find

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aaaaEven tiny, easily overlooked events can completely change the behavior of a complex system, to the point where there is no apparent order to most natural systems we deal with in everyday life.

The weather is one familiar case, but other well-studied examples can be found in chemical reactions, population dynamics, neural networks and even the stock market. Scientists who study “chaos” — which they define as extreme sensitivity to infinitesimally small tweaks in the initial conditions — have observed this kind of behavior only in the deterministic world described by classical physics.

Until now, no one has produced experimental evidence that chaos occurs in the quantum world, the world of photons, atoms, molecules and their building blocks.

This is a world ruled by uncertainty: An atom is both a particle and a wave, and it’s impossible to determine its position and velocity simultaneously. And that presents a major problem. If the starting point for a quantum particle cannot be precisely known, then there is no way to construct a theory that is sensitive to initial conditions in the way of classical chaos. Yet quantum mechanics is the most complete theory of the physical world, and therefore should be able to account for all naturally occurring phenomena.

jessenThe problem is that people don’t see [classical] chaos in quantum systems,” said Professor Poul Jessen of the University of Arizona. “And we believe quantum mechanics is the fundamental theory, the theory that describes everything, and that we should be able to understand how classical physics follows as a limiting case of quantum physics.”

Experiments Reveal Classical Chaos In Quantum World

Now, however, Jessen and his group in UA’s College of Optical Sciences have performed a series of experiments that show just how classical chaos spills over into the quantum world. The scientists report their research in the Oct. 8 issue of the journal Nature in an article titled, “Quantum signatures of chaos in a kicked top.” Their experiments show clear fingerprints of classical-world chaos in a quantum system designed to mimic a textbook example of chaos known as the “kicked top.”

The quantum version of the top is the “spin” of individual laser-cooled cesium atoms that Jessen’s team manipulate with magnetic fields and laser light, using tools and techniques developed over a decade of painstaking laboratory work.

“Think of an atom as a microscopic top that spins on its axis at a constant rate of speed,” Jessen said. He and his students repeatedly changed the direction of the axis of spin, in a series of cycles that each consisted of a “kick” and a “twist”.

bbbbBecause spinning atoms are tiny magnets, the “kicks” were delivered by a pulsed magnetic field. The “twists” were more challenging, and were achieved by subjecting the atom to an optical-frequency electric field in a precisely tuned laser beam. They imaged the quantum mechanical state of the atomic spin at the end of each kick-and-twist cycle with a tomographic technique that is conceptually similar to the methods used in medical ultrasound and CAT scans. The end results were pictures and stop-motion movies of the evolving quantum state, showing that it behaves like the equivalent classical system in some significant ways.

One of the most dramatic quantum signatures the team saw in their experiments was directly visible in their images: They saw that the quantum spinning top observes the same boundaries between stability and chaos that characterize the motion of the classical spinning top. That is, both quantum and classical systems were dynamically stable in the same areas, and dynamically erratic outside those areas.

A New Signature Of Chaos Called ‘Entanglement’

Jessen’s experiment revealed a new signature of chaos for the first time. It is related to the uniquely quantum mechanical property known as “entanglement.”

Entanglement is best known from a famous thought experiment proposed by Albert Einstein, in which two light particles, or photons, are emitted with polarizations that are fundamentally undefined but nevertheless perfectly correlated. Later, when the photons have traveled far apart in space, their polarizations are both measured at the same instant in time and found to be completely random but always at right angles to each other.

“It’s as though one photon instantly knows the result for the other and adjusts its own polarization accordingly,” Jessen said.

By itself, Einstein’s thought experiment is not directly related to quantum chaos, but the idea of entanglement has proven useful, Jessen added.

“Entanglement is an important phenomenon of the quantum world that has no classical counterpart. It can occur in any quantum system that consists of at least two independent parts,” he said.

Theorists have speculated that the onset of chaos will greatly increase the degree to which different parts of a quantum system become entangled. Jessen took advantage of atomic physics to test this hypothesis in his laboratory experiments. The total spin of a cesium atom is the sum of the spin of its valence electron and the spin of its nucleus, and those spins can become quantum correlated exactly as the photon polarizations in Einstein’s example.

In Jessen’s experiment, the electron and nuclear spins remained unentangled as a result of stable quantum dynamics, but rapidly became entangled if the dynamics were chaotic. Entanglement is a buzzword in the science community because it is the foundation for quantum cryptography and quantum computing.

“Our work is not directly related to quantum computing and communications,” Jessen said. “It just shows that this concept of entanglement has tendrils in all sorts of areas of quantum physics because entanglement is actually common as soon as the system gets complicated enough.”

Self-repairing Aircraft Could Revolutionize…

Healing Material

Back in 1993, I lived in LA with my friends. We were acting, taking classes, drinking, taking classes, living the ‘Swingers’ beautiful-babies’ lifestyle and taking more classes. Wait – yeah, and we were taking classes. During one of those trips to class, a lecture of craft presented by the all-knowing, all-wonderful, ‘who’s bigger than Madonna? Michael Jackson! Shut up, Mike’ class of Arlene Golonka, I remember my roommate telling me the story of a puported self-healing aircraft. His friend’s dad, who lived in Simi Valley, worked for one of the big aircraft designers. I think it was McDonnell-Douglass but am not positive. His friend said that his dad told him specifically that his company was “…designing an aircraft that would be able to heal itself after being attacked.”

15 years later and that story breaks. Basically, it’s analogous with the timeline of the stealth technology: 1970’s technology, developed in high-secrecy, revealed publicy in the late 1980’s, and now common place. I ALWAYS knew this story would break one day and here it is. However, since the story has now been ‘pandorized from it’s box,’ it must be old news. Interesting stuff, though – a plane that takes two aspirin and calls you in the morning! WOW!

ScienceDaily (2008-05-19) — A new technique that mimics healing processes found in nature could enable damaged aircraft to mend themselves automatically, even during a flight. br />
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As well as the obvious safety benefits, this breakthrough could make it possible to design lighter airplanes in future. This would lead to fuel savings, cutting costs for airlines and passengers and reducing carbon emissions too…<

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