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<p>Regime of a single 1D wire subband filled</p>

<p>Credit: Dr Maria Moreno</p>
Quantum Effects Observed in ‘One-Dimensional’ Wires
Researchers have observed quantum effects in electrons by squeezing them into one-dimensional ‘quantum wires’ and observing the interactions between them.
<p>This illustration shows a glowing stream of material from a star as it is being devoured by a supermassive black hole in a tidal disruption flare.</p>

<p>When a star passes within a certain distance of a black hole -- close enough to be gravitationally disrupted -- the stellar material gets stretched and compressed as it falls into the black hole. In the process of being accreted, the gas heats up and creates a lot of optical and ultraviolet light, which destroys nearby dust but merely heats dust further out. The farther dust that is heated emits a large amount of infrared light. In recent years, a few dozen such flares have been discovered, but they are not well understood.</p>

<p>Astronomers gained new insights into tidal disruption flares thanks to data from NASA's Wide-field Infrared Survey Explorer (WISE). Studies using WISE data characterized tidal disruption flares by studying how surrounding dust absorbs and re-emits their light, like echoes. This approach allowed scientists to measure the energy of flares from stellar tidal disruption events more precisely than ever before.</p>

<p>JPL manages and operates WISE for NASA's Science Mission Directorate in Washington. The spacecraft was put into hibernation mode in 2011, after it scanned the entire sky twice, thereby completing its main objectives. In September 2013, WISE was reactivated, renamed NEOWISE and assigned a new mission to assist NASA's efforts to identify potentially hazardous near-Earth objects.</p>

<p>Image credit: NASA/JPL-Caltech</p>
Echoes of Black Holes Eating Stars Found
Astronomers now have new insights into tidal disruption flares, thanks to data from NASA's Wide-field Infrared Survey Explorer (WISE).

<p>“Learning from this model, we can understand what’s really going on in these superconductors, and what one should do to make higher-temperature superconductors, approaching hopefully room temperature,” says Martin Zwierlein, professor of physics and principal investigator in MIT’s Research Laboratory of Electronics.</p>

<p>Illustration: Sampson Wilcox</p>
Individual Atoms Behavior Observed
For first time, researchers see individual atoms keep away from each other or bunch up as pairs.
<p>Gaia’s first sky map</p>

<p>Image credit: ESA</p>
Gaia’s First Sky Map
The first catalogue of more than a billion stars from ESA’s Gaia satellite was published – the largest all-sky survey of celestial objects to date.


Attosecond Science opens new Avenues in Femtochemistry
Attosecond Science is a new exciting frontier in contemporary physics, aimed at time-resolving the motion of electrons in atoms, molecules and solids on their natural timescale.
Physicists Confirm Possible Discovery of Fifth Force of Nature
Recent findings indicating the possible discovery of a previously unknown subatomic particle may be evidence of a fifth fundamental force of nature.
Vortex Laser Offers Hope For Moore’s Law
The optics advancement may solve an approaching data bottleneck by helping to boost computing power and information transfer rates tenfold

Science Facts

Amazing GRACE

by NASA Headquarters and ScienceIQ.com

An uneven distribution of mass inside the Earth. The Earth Gravity has an effect on everyone and everything on Earth. Although we can't see it, smell it, taste it or touch it, we know it's there. Although scientists already know quite a bit about this invisible force, many aspects of this fundamental force of nature remain mysterious. In 2002 NASA teamed-up with the German Space Agency to launch the dual satellites that make up GRACE, short for the Gravity Recovery And Climate Experiment. These uniquely-designed twin satellites were developed to provide detailed measurements of Earth's gravity field that help scientists better understand the effects gravity has on Earth's global climate change.

Scientists have studied Earth's gravity for more than 30 years, using both satellite and ground measurements that were of uneven quality,' said Dr. Michael Watkins, GRACE project scientist at NASA's Jet Propulsion Laboratory in California. Errors in some locations were off by as much as 3 feet. Now, these measurements can be taken to within about 1 centimeter (0.4 inches) of accuracy. 'That's progress,' Watkins said. Why do the sensors need to be that sensitive? Because the variations in gravity across Earth's surface are very small and the weight of an object is not the same at every point on Earth. We live on a lumpy, bumpy planet scattered with mountains, valleys and caverns. These features have slightly different masses so as a result, the gravitational force changes ever so slightly across the surface of the Earth.

GRACE maps out these sensitive gravitational changes. GRACE can detect changes as small as one-tenth of the width of a human hair in the separation of the two spacecraft. This distance measurement is combined with Global Positioning data that gives the precise location of the measurement over Earth's surface. Every 30 days, scientists produce gravity maps that are 1,000 times more accurate then maps previously produced that had errors too large to be useful. GRACE monitors the mass and location of water as it moves around on the surface of the Earth, cycling between the land, oceans, and polar ice caps. Scientists also know that gravity is responsible for keeping the air and clouds from drifting away into space, creating the ups and downs of the ocean tides and a force that pulls two objects together. Gravity may be known as the weakest force in all of nature, but it still keeps our feet on the ground and manages to hold our galaxies and solar system together.


An artist
The Brave and Cold Ulysses

Deep space is cold. Very cold. That's a problem--especially if you're flying in an old spaceship. And your power supplies are waning. And the fuel lines could freeze at any moment. Oh, and by the way, ...
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Look, Up in the Sky. It's A Bird. No It's A Meteorite!

Most folks probably think of swallows and the ringing of the Mission bells when the words San Juan Capistrano are heard or seen. This is a popular tradition that celebrates the return of cliff swallow ...
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A Giant X-Ray Machine

The first clear detection of X-rays from the giant, gaseous planet Saturn has been made with NASA's Chandra X-ray Observatory. Chandra's image shows that the X-rays are concentrated near Saturn's equa ...
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Science Quote

'As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality.'

Albert Einstein
(1879-1955)


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