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Mini-EUSO is a high-sensitivity imaging telescope that observes the Earth from the ISS in the near ultraviolet band (290÷430 nm), through the nadir-facing, UV-transparent window in the Russian Zvezda module. The instrument, launched in 2019, has a field of view of 44∘, a spatial resolution on the Earth’s surface of 6.3 km and a temporal sampling rate of 2.5 microseconds. Thanks to its triggering and on-board processing, the telescope is capable of detecting UV emissions of cosmic, atmospheric, and terrestrial origin on different time scales, from a few microseconds up to tens of milliseconds. The optics is composed of two Fresnel lenses focusing light onto an array of 36 Hamamatsu Multi-Anode PhotoMultiplier Tubes, for a total of 2304 pixels. The telescope also contains two cameras in the near-infrared and visible, an 8-by-8 array of Silicon-PhotoMultipliers and a series of UV sensors to manage night-day transitions. The scientific objectives range from the observation of atmospheric phenomena [lightning, Transient Luminous Events (TLEs), ELVES], the study of meteoroids, the search of interstellar meteoroids and strange quark matter, mapping of the Earth’s nocturnal emissions in the ultraviolet range, and the search of cosmic rays with energy above 1021eV. The instrument has been integrated and qualified in 2019, with the final tests in Baikonur prior to its launch. Operations involve periodic installation in the Zvezda module of the station with observations during the crew night time, with periodic downlink of data samples, with the full data being sent to the ground via pouches containing the data disks. Mission planning involves the selection of the optimal orbits to maximize the scientific return of the instrument. In this work, we will describe the various phases of construction, testing, and qualification prior to the launch and the in-flight operations of the instrument on board the ISS.

The use of accelerator hardware for micromagnetics simulations is described, along with some initial results. The accelerator calculates the dipole interactions at 400 gigaflops, allowing large simulations to be performed with arbitrary geometries. Two research programs are highlighted, the simulation of a curved MRAM cell and the simulation of the write head in a computer disk drive.

Development of pulsed lasers for space-based science missions entail many additional challenges compared to terrestrial experiments. For systems requiring short pulses ≪1 ns with energies >100 mJ and fast repetition rates >10 kHz there are currently few if no laser architectures capable of operating with high electrical efficiency >20% and have good system stability. The emergence of a mulit-channel fiber-based Coherent-Amplifying-Network or CAN laser potentially enables such capability for space based missions. Here in this article we present an analysis of two such missions scaling up in pulse energy from ≈100 mJfor a supercontinuum LIDAR application utilising atmospheric filamentation to the higher energy demands needed for space debris remediation requiring ≈10 Jpulses. This scalability of the CAN laser provides pathways for development of the core science and technology where many new novel space applications can be made possible.

Accreting blackholes such as miniquasars and active galactic nuclei can contribute to the highest energy components of intra- (∼1015eV) galactic and extra-galactic components (∼1020eV) of cosmic rays. Alfven wave pulses which are excited in the accretion disk around blackholes propagate in relativistic jets. Because of their highly non-linear nature of the waves, charged particles (protons, ions, and electrons) can be accelerated to high energies in relativistic jets in accreting blackhole systems, the central engine of miniquasars and active galactic nuclei.

Aims.Magnetic elements are thought to be described by flux tube models, and are well reproduced by MHD simulations. However, these simulations are only partially constrained by observations. We observationally investigate the relationship between G-band bright points and magnetic structures to clarify conditions, which make magnetic structures bright in G-band.

The motivations, characteristics and potential performance of the JEM-EUSO project are briefly discussed. [Copyright &y& Elsevier]

EUSO is a super-wide field UV telescope to detect Ultra-High Energy Cosmic-Rays (UHECRs) with energy above . It is attached to the International Space Station (ISS) and observes fluorescence photons emitted by giant air showers produced by UHECR. The three dimensional development of the shower is reconstructed from a series of images of the shower. Phase-A study of EUSO under the European Space Agency (ESA) has successfully finished in July 2004. The phase-B study, however, has been postponed for a long time because of financial problems in ESA and Italy. Then, Japanese and U.S. teams re-defined EUSO as a mission attached to the Japanese Experiment Module/Exposure Facility of ISS. They renamed it as JEM-EUSO and started the preparation targeting the launch in 2012 in the framework of second phase of JEM/EF utilization. The outline of the mission is presented. [Copyright &y& Elsevier]

The interaction of molecular ethylene with the Pd(110) surface has been investigated by means of periodic first-principles density functional theory slab calculations. At 0.5 ML coverage, DFT-GGA-PW91 calculations favor the formation of a short bridge (di-σ type) adsorption mode over an atop (π-bonded) ethylene state by 196 meV. On the other hand, HREELS, NEXAFS, and STM measurements unambiguously reveal the presence of π-bonded ethylene on Pd(110). The possible causes of this wrong site preference in DFT-GGA calculations are discussed.

This work presents a Fortran code to solve the advection equation in 1, 2 and 3 dimensions. The scheme is based on a rational interpolation function. Not only the interpolation profile itself but also its first-order spatial derivatives are predicted by the governing equation. Using the Lagrangian invariant solution of the advection to evaluate the gradients makes the method compact. The scheme is indeed constructed over only one mesh cell. The method has third-order accuracy in the smooth region and appears to be able to suppress spurious numerical oscillations near great gradients.

The Extreme Universe Space Observatory onboard the Japanese Experiment Module (JEM-EUSO) is an international mission designed to explore the origin and nature of the of ultra high-energy cosmic rays (UHECR), with energies , aiming at an integrated exposure of sr yr at . Consisting of a near-UV 2.65 m diameter telescope with a field of view of , JEM-EUSO looks down from space, monitoring the dark side of the Earth, to detect the fluorescence and Cherenkov light emitted along the linear track generated by a cosmic particle traversing the atmosphere. The energy and the arrival direction of each particle will be measured while the all 4π sky is monitored. The primary science goal of the mission is to identify the sources of the highest energy particles, and to measure their flux and spectrum, to unveil the mechanisms for the production, acceleration, and in situ propagation of these extreme particles. Other exploratory objectives of the mission include the study of the galactic and local extragalactic magnetic field; the detection of high-energy gamma rays and neutrinos, and tests of relativity and quantum gravity effects at extreme energies. Other aspects of fundamental physics that will be studied include the top-down models and the behavior of the neutrino cross sections at extreme energies. JEM-EUSO is also expected to conduct a systematic survey of the not yet well known energetic phenomena of the Earthʼs atmosphere. The mission is currently in the phase A study by JAXA and has been included in the ELIPS research pool of the European Space Agency. JEM-EUSO will be launched by an H2B rocket in the Japanese fiscal year 2016 and will be transferred to the ISS by an H2 Transfer Vehicle (HTV). It will be attached to the external experiment platform of the Japanese “KIBO” module of the ISS. In this paper we summarize the science case, the science objectives, the technological and programmatic aspects of this challenging but fascinating mission. [ABSTRACT FROM AUTHOR]