0000000001278960
AUTHOR
A. López García
Improved Method for Orbital Elements Differential Correction.
As was pointed out by IAU in 1976, an important problem in fundamental astronomy is the improvement of the vernal equinox and equator positions. To this aim, it is necessary to know the accurate values of minor planets orbital elements. The classical methods of orbital elements differential corrections are based on linking the observations at different epochs considering equal derivatives respect to the initial and osculating elements. In this paper we present an improved method in which the least squares matrix coefficients is calculated from the integration of the Lagrange planetary equations and its derivatives.
Orbit determination and errors of a star catalogue
Abstract We obtain Ceres orbit taking into account all perturbations and applying correction of phase effect to observations. More than 3000 observations have been used and the results agree with other determinations. We have also investigated the influence of systematic errors of a star catalogue on the observations and its effect on final elements. To that aim, a simulation procedure has been applied to Ceres observations, including different laws for errors of star catalogue versus spherical coordinates. The best relations have been applied to real observations of Ceres, in order to obtain elements and star catalogue corrections. Preliminary results of these calculations are presented.
Automated astrographic plates measuring process
The astrographic plates measuring process applied at the Astronomical Observatory of Valencia has been described.
Figures of equilibrium in close binary systems
The equilibrium configurations of close binary systems are analyzed. The autogravitational, centrifugal and tidal potentials are expanded in Clairaut's coordinates. From the set of the total potential angular terms an integral equations system is derived. The reduction of them to ordinary differential equations and the determination of the boundary conditions allow a formulation of the problem in terms of a single variable.
Digital Image Processing in the Analysis of Astrometric Plates
AbstractIn this paper, we display an improvement to our process of semi-automatic measuring of astrometric plates, in which the photometric sensor is substituted by a CCD system of image getting and digitalization. The advantages of this method are analyzed taking into account the possibilities of the image analysis in the space and frequency domain.
Star Image Identification and Characterization on Astrographic Plates
The automatic identification and characterization of star images has great value for the preliminary analysis and measurement of astrographic plates. Our group at Valencia Observatory is using a small 2-D stage and a CCD camera under computer control to perform systematic measurements of bright asteroid plates. We are also applying this method to the processing of astrographic plates with crowded stellar fields and non-stellar objects in collaboration with the Pulkovo Observatory.
Luxación carpometacarpiana del primer dedo asociada a fractura de trapecio
Presentamos un caso de luxación carpometacarpiana del primer dedo asociada a fractura de trapecio. Fue tratada mediante reducción abierta y fijación interna. El resultado obtenido después de un año de seguimiento fue excelente. Sólo hemos encontrado once casos en la literatura y ninguno tratado como el nuestro. A case of carpometacarpal dislocation of the thumb associated with fracture of the trapezium in presented. It was treated by open reduction and internal fixation. The result after a one year follow-up was excellent. We have found only eleven cases in literature and none was treated like ours.
Luxación radiocarpiana con fractura asociada de la apófisis estiloides radial
Presentamos un caso de luxación dorso lateral del carpo con fractura asociada de la estiloides radial en una mujer de 28 años tras accidente de tráfico. No existieron complicaciones neurovasculares. El tratamiento consistió en reducción y fijación de la estiloides radial con agujas de Kirschner. Después de seis meses de evolución la paciente estaba libre de secuelas.