This paper proposes a nonlinear adaptive position and attitude tracking controller for satellite proximity operations between a target and a chaser satellite. The controller requires no information about the mass and inertia matrix of the chaser satellite, and takes into account the gravitational acceleration, the gravity-gradient torque, the perturbing acceleration due to Earth’s oblateness, a...

Modeling the force of laser pressure on the dynamics of an artificial satellite is studied. The atmospheric effects are taken into consideration. Some important details of the model arising from the thermooptical satellite surface properties are clarified. The model has been exemplified by computing the laser perturbing acceleration for a passive Earth’s satellite (e.g. the satellite Ajisai). T...

We analyze the origin of the hard X-ray flux from the Coma cluster observed by the Beppo-SAX satellite. This flux is typically assumed to be produced by nonthermal particles accelerated in the Coma medium. We show, however, that in the case of in-situ acceleration of particles from the thermal pool, the hard X-rays in the range of Beppo-SAX observations (30−80 keV) are generated by bremsstrahlu...

in this paper, the range doppler algorithm (rda) for synthetic aperture radar moving on a ballistic trajectory is presented. the 3-dimension acceleration and non-uniform trajectory cause decreases in efficiency of conventional imaging algorithms. in this paper, the analytical expression for the 2-d signal spectrum for ballistic trajectory using taylor series expansion and series reversion is de...

Cameras automatically apply non-linear transformations to the sensor data, allowing for perceptually-uniform quantization suited to standard dynamic range displays in dim conditions. In the cinema industry, data is recorded in raw (linear) format and non-linearly corrected in post-production by a skilled technician who optimizes image appearance for cinema (dark) conditions. We propose a method...

Measurements with satellite and sounding rocket borne instruments contain important information on remote and local processes in regions containing matter in the plasma state. The characteristic features of the particle distributions can be used to explain the morphology and dynamics of the different plasma populations. Charged particles are lost from a region due to precipitation into the atmo...

Context. Massive protostars have associated bipolar outflows with velocities of hundreds of km s. Such outflows can produce strong shocks when interact with the ambient medium leading to regions of non-thermal radio emission. Aims. We aim at exploring under which conditions relativistic particles are accelerated at the terminal shocks of the protostellar jets and can produce significant gamma-r...

More than 27 years of high precision satellite altimetry enables analysis recent changes in global mean sea level (GMSL). Several previous studies present estimates the trend and acceleration GMSL; however, all are exclusively performed with data from TOPEX/Poseidon, Jason-1, Jason-2 Jason-3 missions (TPJ data). In this study we extend record both time space by including independent ERS-1, ERS-...

We have conducted multiwavelength observations of several northern TeV blazars employing the ground-based γ-ray observatories MAGIC and HESS, the optical KVA telescope, and the Suzaku X-ray satellite. The data taken in 2006 establish measurements of the contemporaneous spectral energy distributions of the rapidly variable blazar emission over a wide range of frequencies. Results allow us to tes...