Medium energy neutral atom (MENA) imager for the IMAGE mission

The Medium Energy Neutral Atom (MENA) imager was developed in response to the Imaging from the Magnetopause to the Aurora for Global Exploration (IMAGE) requirement to produce images of energetic neutral atoms (ENAs) in the energy range from 1 to 30 keV. These images will be used to infer characteristics of magnetospheric ion distributions. The MENA imager is a slit camera that images incident ENAs in the polar angle (based on a conventional spherical coordinate system defined by the spacecraft spin axis) and utilizes the spacecraft spin to image in azimuth. The speed of incident ENAs is determined by measuring the time-of-flight (TOF) from the entrance aperture to the detector. A carbon foil in the entrance aperture yields secondary electrons, which are imaged using a position-sensitive Start detector segment. This provides both the one-dimensional (1D) position at which the ENA passed through the aperture and a Start time for the TOF system. Impact of the incident ENA on the 1D position-sensitive Stop detector segment provides both a Stop-timing signal and the location that the ENA impacts the detector. The ENA incident polar angle is derived from the measured Stop and Start positions. Species identification (H vs. O) is based on variation in secondary electron yield with mass for a fixed ENA speed. The MENA imager is designed to produce images with 8°×4° angular resolution over a field of view 140°×360°, over an energy range from 1 keV to 30 keV. Thus, the MENA imager is well suited to conduct measurements relevant to the Earth's ring current, plasma sheet, and (at times) magnetosheath and cusp.     

Influence of Autoclave Molding Modes and Stack Structure on Porosity of Composite Materials

Influence of stack structure on porosity of composite materials at different modes of autoclave molding was studied. To reduce porosity of composite materials, specific stack structure and molding mode are recommended.     

Equatorial predictions from a new neural network based global foF2 model

A new neural network (NN) based global empirical model for the foF2 parameter, which represents the peak ionospheric electron density, has been developed using extended temporal and spatial geophysical relevant inputs. It has been proposed that this new model be considered as a suitable replacement for the International Union of Radio Science (URSI) and International Radio Consultative Committee (CCIR) model options currently used within the International Reference Ionosphere (IRI) model for the purpose of F2 peak electron density predictions. The most recent version of the model has incorporated data from 135 global ionospheric stations including a number of equatorial stations.     

Bioaugmentation in growing plants for lunar bases

Microorganisms may be a key element in a precursory scenario of growing pioneer plants for extraterrestrial exploration. They can be used for plant inoculation to leach nutritional elements from regolith, to alleviate lunar stressors, as well as to decompose both lunar rocks and the plant straw in order to form a protosoil. Bioleaching capacities of both French marigold (Tagetes patula L.) and the associated bacteria in contact with a lunar rock simulant (terrestrial anorthosite) were examined using the model plant-bacteria microcosms under controlled conditions. Marigold accumulated K, Na, Fe, Zn, Ni, and Cr at higher concentrations in anorthosite compared to the podzol soil. Plants inoculated with the consortium of well-defined species of bacteria accumulated higher levels of K, Mg, and Mn, but lower levels of Ni, Cr, Zn, Na, Ca, Fe, which exist at higher levels in anorthosite. Bacteria also affected the Са/Mg and Fe/Mn ratios in the biomass of marigold grown on anorthosite. Despite their growth retardation, the inoculated plants had 15% higher weight on anorthosite than noninoculated plants. The data suggest that the bacteria supplied basic macro-and microelements to the model plant.     

VLBI for better gravimetry in SELENE

The Japanese lunar explorer SELENE (SElenological and Engineering Explorer), to be launched in 2007, will for the first time utilize VLBI observations in lunar gravimetry investigations. This will particularly improve the accuracy to which the low degree gravitational harmonics and the gravity field near the limb can be measured, and when combined with Doppler measurements will enable three-dimensional information to be extracted. Differential VLBI Radio sources called VRAD experiment involves two on-board sub-satellites, Rstar and Vstar. These will be observed using differential VLBI to measure the trajectories of the satellites with the Japanese network named VERA (VLBI Exploration of Radio Astrometry) and an international VLBI network.     

Properties of Sharp and Large Changes in the Solar Wind Ion Flux (Density)

The results of a detailed study of large (by 20% and more) and sharp (faster than ten minutes) changes of the ion flux in the solar wind are presented. The data are provided by regular measurements onboard the INTERBALL-1 satellite in the period 1996–1999. Using statistical analysis, we obtained the distribution of these changes in their absolute and relative strength. It is shown that, for a considerable proportion of the events, such sharp and large changes of the ion flux (density) take place under conditions of fairly constant values of the solar wind velocity and of both the magnitude and components of the interplanetary magnetic field.     

Features of the radial diffusion of energetic electrons in the middle Jovian magnetosphere

In this paper, the radial diffusion of energetic electrons in the Jovian radiation belts is considered. It is noted that the influence of global resonance in the electron radiation belts on the ring current provides original electrical pulses in the middle magnetosphere. The values of the random transfer of energetic electrons across the magnetic shells, which are associated with electrical pulses, are determined. An expression for radial diffusion is obtained. The functional form and radial diffusion coefficient are compared with those known from Jovian magnetosphere experimental data.     

JIRAM,the Jovian Infrared Auroral Mapper

JIRAM is an imager/spectrometer on board the Juno spacecraft bound for a polar orbit around Jupiter. JIRAM is composed of IR imager and spectrometer channels. Its scientific goals are to explore the Jovian aurorae and the planet’s atmospheric structure, dynamics and composition. This paper explains the characteristics and functionalities of the instrument and reports on the results of ground calibrations. It discusses the main subsystems to the extent needed to understand how the instrument is sequenced and used, the purpose of the calibrations necessary to determine instrument performance, the process for generating the commanding sequences, the main elements of the observational strategy, and the format of the scientific data that JIRAM will produce.     

The Modern Near-Surface Martian Climate: A Review of In-situ Meteorological Data from Viking to Curiosity

We analyze the complete set of in-situ meteorological data obtained from the Viking landers in the 1970s to today’s Curiosity rover to review our understanding of the modern near-surface climate of Mars, with focus on the dust, CO₂ and H₂O cycles and their impact on the radiative and thermodynamic conditions near the surface. In particular, we provide values of the highest confidence possible for atmospheric opacity, atmospheric pressure, near-surface air temperature, ground temperature, near-surface wind speed and direction, and near-surface air relative humidity and water vapor content. Then, we study the diurnal, seasonal and interannual variability of these quantities over a span of more than twenty Martian years. Finally, we propose measurements to improve our understanding of the Martian dust and H₂O cycles, and discuss the potential for liquid water formation under Mars’ present day conditions and its implications for future Mars missions. Understanding the modern Martian climate is important to determine if Mars could have the conditions to support life and to prepare for future human exploration.     

Model for the VLF/LF radio signal anomalies formation associated with earthquakes

The influence of quasi-static electric field of seismic origin on the characteristics of the internal gravity waves (IGWs) in the Earth’s ionosphere is considered. The electric field in the ionosphere arises due to the injection of charged aerosols into the atmosphere, formation of an EMF in the near Earth atmosphere and perturbation of the conductive electric current in the global electric circuit. Amplification of the electric current in seismic zone is accompanied by the formation of perturbation of the lower ionosphere that affects the amplitude and phase of VLF/LF signals. The action of the electric field on the IGWs is connected with the appearance of the Ampere’s force in the ionosphere. In the spectral range of these waves the latter acts on the neutral component of the ionosphere plasma. As the result of this interaction the ionosphere starts to support the discrete spectrum of oscillations. Periods of their maximums increase as numbers of natural sequence. The existence of such peculiarities of the waves in the ionosphere is confirmed by observations.