An analysis of temperature fields in rotating fluid

A possible variant presented for solving the equation of motion of a rotating flow is more general with respect to the variants known in the literature. On the basis of the simultaneous solution of the equations of motion and energy, the temperature fields are determined under changes of the rotation nature.     

Some regularities in the relationship of limb coronal mass ejections with eruptive prominences and post-eruptive arcades

A positive correlation is shown to exist between the angular sizes (in the sky plane) of eruptive prominences and/or post-eruptive arcades and coronal mass ejections (CMEs) associated with them. New regularities are found that characterize the relationship between the latitude of eruptive prominences (post-eruptive arcades) and the latitude position of CMEs associated with them in the field of view of a coronagraph. An interpretation of these regularities is given.     

Fiber-optic gyros and quartz accelerometers for motion control

In article the opportunity of use strapdown inertial navigation system (SINS) on the base of fiber-optic gyroscopes and quartz accelerometers corrected from star sensors and satellite navigation equipment (SNE) for perspective interplanetary spacecrafts motion control on phases of interplanetary trajectory insertion, trajectory correction, and braking during transition to Mars orbit is investigated. Results of onboard control complex accuracy characteristics estimation are presented at the given dynamic spacecraft scheme which is taking into account the liquid oscillations in tanks and structure elements elasticity. At modelling the errors of measuring devices installation, errors of SINS initial alignment and instrumental errors of SINS sensitive elements, variation of control engines parameters were taken into account. The structure of the developed complex of imitation modelling of interplanetary spacecraft controlled motion is resulted. Estimations of active flight legs realization accuracy were received by a method of statistical modelling of spacecraft controlled motion     

Solar wind turbulence during the solar cycle deduced from Galileo coronal radio-sounding experiments

Seven coronal radio-sounding campaigns were carried out during the active lifetime of the Galileo spacecraft in the years 1994–2002. The observational data analyzed in the present work are S-band frequency fluctuation measurements recorded during the solar conjunctions at different phases of solar activity cycle #23, specifically: periods near solar maximum (three conjunctions), near solar minimum (three conjunctions) and during the ascending phase (one conjunction). These data are all applicable to low heliographic latitudes, i.e. to the slow solar wind. The rms frequency fluctuation and power-law index of the frequency fluctuation temporal spectra are determined as a function of heliocentric distance. The turbulence power spectrum tends to be flatter inside ca. 20 solar radii during all phases of the solar cycle. This coincides with a transition in the flow from the inner acceleration region to the outer region of constant velocity. The radial falloff rate and absolute level of the rms frequency fluctuation are essentially invariant over the solar cycle.     

Integral-projection method and singularities of its application in mating shells with inconsistent parameters of approximation

We describe a numerical integral-projection method used by the authors for the approximate solution of systems of interrelated two-dimensional linear boundary-value problems in mechanics of composite shell systems. The method is based on discretization in each shell substructure of a two-dimensional problem along one of coordinates using a projection-grid variant of the Galerkin-Petrov method and its subsequent transformation to a system of ordinary differential equations; by integration and introduction of sought functions as unknown derivatives, the system is reduced to a system of integral equations being solved by the method of mechanical quadratures. The method is characterized by the fact that its application requires no additional conditions of conformity with discretization parameters of substructures being mated.     

Evolution of the orbital elements for objects with high area-to-mass ratios in geostationary transfer orbits

A new population of uncatalogued objects in geosynchronous Earth orbits (GEO), with a mean motion of about 1 rev/day and eccentricities up to 0.6, has been identified recently. The first observations of this new type of objects were acquired in the framework of the European Space Agency’s (ESA) search for space debris in GEO and the geostationary transfer orbit (GTO) using the ESA 1-m telescope on Tenerife. Earlier studies have postulated that the perturbations due to the solar radiation pressure can lead to such large eccentricities for GEO objects with a high area-to-mass ratio (A/M). The simulations showed that the eccentricities of GEO objects with large A/M exhibit periodic variations with periods of about one year and amplitudes depending on the value of A/M. The findings of these studies could be confirmed by observations from the ESA 1-m telescope on Tenerife.