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A vast bubble of hot, rarefied gas has been revealed as a source of cosmic rays - the mysterious particles that batter the Earth continuously. The observation of the so-called superbubble, measuring more than 100 light-years across, was made using gamma rays collected by NASA's Fermi satellite and sheds light on the origin of cosmic rays in regions of massive-star formation.

Two apps - the Distributed Electronic Cosmic-ray Observatory (DECO) and Cosmic rays Found in Smartphones (CrayFIS) - transform smartphones into miniature cosmic-ray detectors. They use the CMOS chips inside phones' onboard cameras to detect the secondary particles produced when cosmic rays - energetic, charged subatomic particles arriving from beyond the solar system - collide with air molecules in the Earth's atmosphere

"One of the leading theories describing how the most energetic cosmic rays are produced may need a rethink in light of a new study by physicists at the IceCube Neutrino Observatory in Antarctica. The team had set out to detect the extremely energetic neutrinos that are expected to be produced alongside high-energy cosmic rays in the violent explosions that mark the deaths of massive stars - but after looking at hundreds of these explosions, no such neutrinos have been found. "

good news for x-ray astronomers

Deepest X-ray Image Ever Reveals Black Hole Treasure Trove An unparalleled image from NASA's Chandra X-ray Observatory gives astronomers the best look yet at the growth of black holes over billions of years beginning soon after the Big Bang.

High energy gamma rays are shown to be bent slightly by specialized lenses. The effect is likely due to pair-creation close to the atomic nuclei in the material.

Researchers report a new way to use X-rays to probe the properties of solid materials.

Short GRBS are formed when neutron stars (in a binary system) slam into one another. On the other hand, long GRBs are a result of massive stars going supernova. Stars end their lives in violent explosions, typically leaving behind remnants like neutron stars.

Abstract: In the last 3000 yr, one significant and rapid increase in the concentration of 14C in tree rings was observed; it corresponds to a gamma-ray energy input of 7x10^24 erg at Earth within up to one year in AD 774/5 (Miyake et al. 2012).

Now we just need an x-ray mode and we are done.

New experiments and supercomputer computations discovered that iron oxide undergoes a new kind of transition under deep Earth conditions. Iron oxide, FeO, is a component of the second most abundant mineral at Earth's lower mantle, ferropericlase. The finding, published in an upcoming issue of Physical Review Letters, could alter our understanding of deep Earth dynamics and the behavior of the protective magnetic field, which shields our planet from harmful cosmic rays.

News about the warp drive based on the original Alcubierre metric but with modified shape function. Focus of the reserach was on the interaction between warp bubble and cosmic particles. Result: People on board need shielding. People at the journey's destination might get roasted (by Gamma rays if you want to know).

Physicists in the US have made the first ultrathin flat lens. Thanks to its flatness, the device eliminates optical aberrations that occur in conventional lenses with spherical surfaces. As a result, the focusing power of the lens also approaches the ultimate physical limit set by the laws of diffraction.

Really nice indeed! The new flat ultrathin lens is different in that it is a nanostructured "metasurface" made of optically thin beam-shaping elements called optical antennas, which are separated by distances shorter than the wavelength of the light they are designed to focus. These antennas are wavelength-scale metallic elements that introduce a slight phase delay in a light ray that scatters off them. The metasurface can be tuned for specific wavelengths of light by simply changing the size, angle and spacing between the nanoantennas. "The antenna is nothing more than a resonator that stores light and then releases it after a short time delay," Capasso says. "This delay changes the direction of the light in the same way that a thick glass lens would." The lens surface is patterned with antennas of different shapes and sizes that are oriented in different directions. This causes the phase delays to be radially distributed around the lens so that light rays are increasingly refracted further away from the centre, something that has the effect of focusing the incident light to a precise point.

In a feat never before observed, a newly discovered pulsar shifts back and forth between emitting X-rays and radio waves. The discovery represents a long-sought "middle" phase in the life of these powerful objects.

Theorists expect that positronium, a sort of 'atom' consisting of an electron and an anti-electron, can be used to make a powerful gamma-ray laser. Scientists now report detailed calculations of the dynamics of a positronium BEC. This work is the first to account for effects of collisions between different positronium species.

Good news for the imaging community: simpler and smaller x-ray sources are on the way.

essentially they made an experiment that does not prove or disprove anything -big deal-... what is the scientific value of "strongly disfavour"??? I also like the sentence "most models do not have exact predictions for the energy scale associated with this violation of Lorentz invariance" ... but if this is true WHAT IS THE POINT OF THE EXPERIMENT!!!! God, physics is in trouble ....

hum, null result experiments are not useless !!! there is always the hope of finding "something wrong", which would lead to a great discovery. For the state of theoretical physics (the "no exact predictions" quote), i totally agree that physics is in trouble... That's what happen when physicists don't care anymore about experiments...! All you can do now is drawing "nice"graph with upper bounds on some parameters of an all tunable weird theory !

Acasa was born out of Singularity University, a unique, world-changing institution founded in 2008 by Ray Kurzweil and Peter Diamandis. After nine weeks at NASA Ames, the home of Singularity University, four teams emerged with projects focused on one common goal-to positively affect the lives of one billion people over ten years. Our team has designed a business plan to leverage advances in rapid 3D additive manufacturing technologies in order to construct affordable, customizable housing for the developing world. This environmentally sustainable solution has the potential to create a powerful new paradigm for improving housing construction using local resources.

cool video, i'd like to see that in reality... Though i'm not sure it would be less expansive than the very cheap workers you can get on site ! You need to build the robot, to bring it on-site, highly specialised enginneers to supervize the project, etc...

yeah I am not sure about that either but the idea seems nice though

Sounds like one of Calvin's alibis: Aliens! Dad, aliens! A sarcastic Venusian entered the kitchen...

i think they could also be a cause for Greece's economic crisis

Well, then I suggest to elect Spaceman Spiff instead of Papandreou as Prime Minister! :-)

are these all nutheads or is there some truth in the comments to this article??