Promoting Earth-Based Radar Astronomical Observations of the Moon

Earth-based radar astronomical observations provide information on surface characteristics, orbits, and rotations for a wide variety of solar system objects. Based on compound radio telescopes, both the Chinese VLBI (Very Long Baseline Interferometry) network (CVN) and the Russian VLBI network (Quasar), in cooperation with the Chinese radar transmitters, we present the current ground radar astronomical observations of the moon. The spectrum of the reflected radio signals was obtained and the Doppler frequency shift in bi-static radar mode was measured. Radar albedo of the observed region and power ratios of the reflected signals with left- and right-hand circular polarizations were determined, allowing us to study the radar reflectivity and near-surface wavelength-scale roughness of the moon. Future developments on radar astronomy are also discussed in the paper.

Hybrid Dual-Polarization Synthetic Aperture Radar

Compact polarimetry for a synthetic aperture radar (SAR) system is reviewed. Compact polarimetry (CP) is intended to provide useful polarimetric image classifications while avoiding the disadvantages of space-based quadrature-polarimetric (quad-pol) SARs. Two CP approaches are briefly described, π/4 and circular. A third form, hybrid compact polarimetry (HCP) has emerged as the preferred embodiment of compact polarimetry. HCP transmits circular polarization and receives on two orthogonal linear polarizations. When seen through its associated data processing and image classification algorithms, HPC’s heritage dates back to the Stokes parameters (1852), which are summarized and explained in plain language. Hybrid dual-polarimetric imaging radars were in the payloads of two lunar-orbiting satellites, India’s Earth-observing RISAT-1, and Japan’s ALOS-2. In lunar or planetary orbit, a satellite equipped with an HCP imaging radar delivers the same class of polarimetric information as Earth-based radar astronomy. In stark contrast to quad-pol, compact polarimetry is compatible with wide swath modes of a SAR, including ScanSAR. All operational modes of the SARs aboard Canada’s three-satellite Radarsat Constellation Mission (RCM) are hybrid dual-polarimetric. Image classification methodologies for HCP data are reviewed, two of which introduce errors for reasons explained. Their use is discouraged. An alternative and recommended group of methodologies yields reliable results, illustrated by polarimetrically classified images. A survey over numerous quantitative studies demonstrates HCP polarimetric classification effectiveness. The results verify that the performance accuracy of the HCP architecture is comparable to the accuracy delivered by a quadrature-polarized SAR. Four appendices are included covering related topics, including comments on inflight calibration of an HCP radar.

X-ray Fourier ptychography

To a large extent, the performance of imaging systems is determined by their objectives, which affect properties as varied as collection efficiency, resolving power, and image distortions. Such limitations can be addressed by so-called aperture synthesis, a technique used, for instance, in radar, astronomy, and, increasingly, microscopy. Here, we apply such techniques to x-ray imaging and demonstrate how Fourier ptychography can be used at transmission x-ray microscopes to increase resolution, provide quantitative absorption and phase contrast, and allow for corrections of lens aberrations. We anticipate that such methods will find common and frequent applications, alleviating a number of limitations imposed by x-ray optical elements, offering an alternative approach to phase contrast imaging, and providing novel opportunities to mitigate radiation damage.

Computing The Irregularity Strength of Planar Graphs

The field of graph theory plays a vital role in various fields. One of the important areas in graph theory is graph labeling used in many applications such as coding theory, X-ray crystallography, radar, astronomy, circuit design, communication network addressing, and data base management. In this paper, we discuss the totally irregular total k labeling of three planar graphs. If such labeling exists for minimum value of a positive integer k, then this labeling is called totally irregular total k labeling and k is known as the total irregularity strength of a graph G. More preciously, we determine the exact value of the total irregularity strength of three planar graphs.

Kinetic waves - dynamics of light propagation

An in-depth analysis of the dynamics connected to the Doppler-effect brings clear light to elements of contradiction with the original ground on which the axiom of the constancy of lightspeed was based. Thereby, with regard to electromagnetic phenomenology, the duality waves/particles and the wavy dynamic of light-propagation suggest the existence of a natural kind of waves, which differently from the classic ones, are originating by kinetic thrust and propagating, also though vacuum, by inertial force. The model taken into consideration, to which has been given the name of “kinetic waves” is, like the classic one, a concretely existing natural phenomenon which can also be visually perceived if produced on molecular scale. Moreover kinetic waves seem to offer many more points of similarity, in dynamic and behavior, with the electromagnetic waves, than the classic model. Applying the obtained results on the astrophysical field, taking as example the quasar 3C-273, the recently found, most far galaxy GN-z11 and the galaxy NGC 224 (better known as Andromeda), can mathematically and concretely be sustained that none of the energy sources we optically perceive, showing a Doppler-shift, nor is approaching nor regressing. In the appendix, a suggested and accurately described experiment on base of Radar Astronomy to possibly confirm the validity of the model presented by this article.

Research on Kinetic Waves and Applications

The duality waves/particle and the dynamic of propagation of electromagnetic emanations suggest the existence of a natural kind of waves, which differently from de classic ones, are originating by kinetic thrust and propagating, also though vacuum, by inertial force. The model taken into consideration, to which has been given the name of “kinetic waves” is, like the classic one, a concretely existing natural phenomenon which can also be visually perceived if produced on molecular scale. Results suggest, by giving consistent mathematical proof, that kinetic waves offer many more points of similarity, in dynamic and behavior, than the classic ones, which were taken, since the discovery of electromagnetic waves, as basic model.Applying the obtained results relatively to this model, to the astrophysical red-shift, taking as example the quasar 3C-273 and the recently found, most far galaxy GN-z11, we could find a mathematical sustainable and logic answer about still unsolved problems with regard to the origin and the dynamic of the universe.In the appendix, a suggested and accurately described experiment on base of Radar Astronomy to possibly confirm the validity of this model.