Volume 11 Issue 8, August 2015

What is it about the Hubble Space Telescope that so captivates its users and the public at large? I offer my personal views on this iconic telescope.

This year, NASA's Dawn and New Horizons rendezvoused with Ceres and Pluto, respectively. These worlds, despite their modest sizes, have much to teach us about the accretion of the Solar System and its dynamical evolution.

A new NASA mission will reveal the electron-scale physics of magnetic reconnection, a process that connects our planet to the rest of the Universe.

On astronomical scales, gravity is the engine of the Universe. The launch of LISA Pathfinder this year to prepare the technology to detect gravitational waves will help us 'listen' to the whole Universe.

Quantum technologies, including quantum sensors, quantum communication and quantum metrology, represent a growing industry. Out in space, such technologies can revolutionize the way we communicate and observe our planet.

Light has long been used to detect the chirality of molecules but high-order harmonic generation now provides access to these chiral interactions on ultrafast timescales.

The discovery of a new correlation between the incident field and the laser speckle created by multiple scattering takes us a step closer to imaging in turbid media.

Decades-long repeat observations of supernova 1987A offer us unique, real-time insights into the violent death of a massive star and its long-term environmental effects, until its eventual switch-off.

When do structures comprising a few crystalline sheets become truly two dimensional? The number of layers certainly plays a role, but in trilayer graphene, the way they're stacked matters too — as shown in a series of Nature Physics papers from 2011.

Superpositions of massive objects would be hard to spot on Earth even in well-isolated environments because of the decoherence induced by gravitational time dilation.

Similar to orbital angular momentum-carrying optical beams, it is now possible to engineer structured electron beams that could find applications in imaging, nanofabrication and the study of fundamental phenomena.

Vacuum fluctuations in a ground-state mechanical oscillator are hard to distinguish from noise, but by using the coupling with a superconducting qubit in a microwave cavity one can amplify and convert them to directly measurable real photons.

Transistors rely on electrical gates to control conductance but this is challenging on the atomic-scale. It is now shown that individual charged atoms can be used to electrostatically gate a single-molecule transistor with sub-ångström precision.

Weyl semimetals are predicted to exhibit a host of unusual transport properties. NbP, a system predicted to share characteristics of both normal and Weyl semimetals, is now shown to have a very large, non-saturating magnetoresistance.

Contrary to common belief, bilayer graphene is not defect-free: the abundance of partial dislocations leads to a mosaic-like network structure. As a result, as now shown, the magnetoresistance of bilayer graphene depends linearly, rather than quadratically, on the external magnetic field.

Molecules that are mirror images of each other usually behave identically, unless they are interacting with other chiral objects. High-harmonic generation can provide access to the dynamics of chiral interactions on ultrafast timescales.

Sensory nervous systems adapt to their environment—a mechanism thought to ensure network dynamics remain critical. Visual cortex experiments show that adaptation maintains criticality even as sensory input drives the system away from this regime.

A foreground galaxy cluster is magnifying a more distant blazar by gravitationally bending the emitted radiation. Using such a lens, it is possible to resolve a jet close to the central supermassive black hole as being the source of the gamma rays.

Gravity and quantum mechanics are expected to meet at extreme energy scales, but time dilation could induce decoherence even at low energies affecting microscopic objects—a prospect that could be tested in future matter-wave experiments.

The pressure that a fluid of self-propelled particles exerts on its container is shown to depend on microscopic interactions between fluid and container, suggesting that there is no equation of state for mechanical pressure in generic active systems.

Materials expected to support a quantum-spin-liquid phase are typically characterized by geometrical frustration. A new candidate has a distorted lattice that compensates for diminished frustration with reduced dimensionality.

Light propagating through a scattering medium exhibits correlations in the transmission matrix. A theoretical and experimental study uncovers intensity correlations that survive multiple scattering, which could be exploited for imaging.

New three-dimensional simulations of magnetic reconnection suggest the existence of secondary reconnection sites that could be observed by the new NASA Magnetospheric MultiScale Mission.

Two's company.

The success of a number of space missions and the twenty-fifth anniversary of the launch of the Hubble Space Telescope make 2015 an exciting year for space science. This Focus celebrates these achievements. Image credit: NASA/ESA.