A snapshot of a simulation showing a binary black hole formed in the center of a dense star cluster. Credit: Northwestern Visualization/Carl Rodriguez

When LIGO’s twin detectors first picked up faint wobbles in their respective, identical mirrors, the signal didn’t just provide first direct detection of gravitational waves—it also confirmed the existence of stellar binary black holes, which gave rise to the signal in the first place. Stellar binary black holes are formed when two black holes, created out of the remnants of massive stars, begin to orbit each other. Eventually, the black holes merge in a spectacular collision that, according to Einstein’s theory of general relativity, should release a huge amount of energy in the form of gravitational waves.

Now, an international team led ...

fMRI is used to highlight select implant sites in the somatosensory cortex. Electrodes implanted in this region were able to stimulate neurons that produced physical sensations, like a squeeze or tap, in the arm of a paralyzed man. Credit: Courtesy of the Andersen lab

For the first time, scientists at Caltech have induced natural sensations in the arm of a paralyzed man by stimulating a certain region of the brain with a tiny array of electrodes. The patient has a high-level spinal cord lesion and, besides not being able to move his limbs, also cannot feel them. The work could one day allow paralyzed people using prosthetic limbs to feel physical feedback from sensors placed on these devices.

The research was done in the laboratory of Richard Andersen, James G...

A Chandra X-ray Observatory image of the globular cluster 47 Tucanae. The image is about ten light-years across, and shows many cataclysmic variables (CVs), white dwarf stars that accrete from a companion star. Astronomers have discovered twenty-two new CVs in the cluster, and used the statistics to argue that, unlike many clusters which have bright, recently formed CVs, the ones here are older or even primordial. Credit: NASA/CXC/Michigan State/A.Steiner et al. 2014

Cataclysmic variable stars (CVs) are white dwarf stars that are accreting from an orbiting, low mass binary companion star. The accretion is facilitated by the proximity of the stars; typical orbital periods range from about 1 to 10 hours...

This is a schematic of the first-ever plasmomechanical oscillator (PMO), developed by NIST researchers. The orange-white ovals represent the localized plasmon oscillations. The cantilever, containing the gold cuboid nanoparticle, lies dead center. The series of white curves represents the electrical field applied to the cantilever. Data at right indicates that the device can lock onto and greatly amplify weak signals that oscillate at frequencies close to those of the PMO. Credit: B. Roxworthy/NIST

Researchers have for the first time created a plasmomechanical oscillator, a nanometer-scale device that is no bigger than a red blood cell but has myriad technological applications...