Physics & Astronomy News

<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

The Devil's In The Details

by Gene Mascoli and

The Mars Climate Orbiter: Image Courtesy NSSDC Did you ever make a mistake converting English numbers to metric numbers? Let's hope that your mistake didn't cost anyone $125 million dollars. That's what happened to NASA. The Mars Climate Orbiter's mission to study Martian weather and climate was a part of NASA's faster-better-cheaper philosophy of the 1990s. On September 23, 1999, after firing its main engine to enter an orbit around the planet Mars, it crashed into the planet and was destroyed. So what happened?

The mission had proceeded normally and was believed to be on track as the spacecraft went behind Mars causing a planned 20 minute loss of its signal as it was occulted by the planet (occult means to hide). The 20 minutes came and went with no resumption of contact with the spacecraft. NASA now believes that the Mars Climate Orbiter was destroyed because of a navigation error which caused a much lower angle of descent into the Martian atmosphere, an angle of descent outside the structural capabilities of the spacecraft. NASA's disappointment was understandable. What wasn't understandable was the reason that the target altitude of 80 to 90 kms was missed.

To quote NASA, '[t]he 'root cause' of the loss of the spacecraft was the failed translation of English units into metric units in a segment of ground-based, navigation-related mission software, as NASA has previously announced.' In plain English, spacecraft engineers failed to coordinate their numbers. It turns out that a team of engineers at NASA was using metric numbers to calculate the target altitude, while the company that built the spacecraft was using feet and inches. A trip of 35 million miles was destined to failure because of a few inches and millimeters. So next time you're doing some math problems, remember what your teacher told you -- check your work.

An artist
Not Quite A Planet

Astronomers have dubbed it 'Quaoar' (pronounced kwa-whar) after a Native American god. It lies a billion kilometers beyond Pluto and moves around the Sun every 288 years in a near-perfect circle. Unti ...
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What is Dark Energy?

Because he originally thought the Universe was static, Einstein conjectured that even the emptiest possible space, devoid of matter and radiation, might still have a dark energy, which he called a 'Co ...
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The brilliant stars seen in this image are members of the popular open star cluster known as the Pleiades, or Seven Sisters.
How Far Are The Seven Sisters?

The Pleiades cluster, named by the ancient Greeks, is easily seen as a small grouping of stars lying near the shoulder of Taurus, the Bull, in the winter sky. Although it might be expected that the di ...
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Science Quote

'The strength and weakness of physicists is that we believe in what we can measure. And if we can't measure it, then we say it probably doesn't exist. And that closes us off to an enormous amount of phenomena that we may not be able to measure because they only happened once. For example, the Big Bang. ... That's one reason why they scoffed at higher dimensions for so many years. Now we realize that there's no alternative... '

Michio Kaku

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