Artefacts in applications of the global gravity field and topographic models based on satellite and terrestrial data of diverse kinds are studied. Various types of artefacts are presented and analysed with the aim to understand how the artefacts originated, how to reduce them (if feasible) and to avoid misinterpretations in geoscience. We work with the gravity aspects (gravity anomalies, the Marussi tensor of the second derivatives of disturbing potential, gravity invariants and their specific ratio, strike angles, and virtual deformations), and with surface or bedrock topography. Examples for the Earth, the Moon, and Mars are presented., Jaroslav Klokočník, Jan Kostelecký, Aleš Bezděk and Gunther Kleteschka., and Obsahuje bibliografii
Formulas for recurrent determination of inclination function and their derivatives are presented. The main goal of this derivation is to attain relative numerical stability for higher degree and orders. The problem of practical application in a computer is discussed., Predlagajutsja rekurrentnyje formuly vyčislenija normirovannych funkcij naklona orbity. Glavnaja ich cel' - povyšenije otnositel'noj čislennoj stabil'nosti dlja vysšich stepenej i porjadkov. V stat'e rešena tože problema realizacii na EVM., and Celý článek bude uveden v Bull. Astron. Inst., sv. 36
The aim of this paper is the analysis of temporal changes in multipath propagation errors on the pseudorange GNSS signal used for positioning, and its behavior during the calendar year (the quality of signal depends on e.g. foliage of trees, changes reflectivity surfaces due to rain or snow, etc.). The analysis was performed on data measured on a stationary point at Geodetic Observatory Pecný at Ondřejov, where one day was chosen as a constant time unit. Given the relatively highly unfavorable configuration of the experiment, RMS value of multipath is up to 60 cm on C1 and 40 cm on C2. These values vary with different weather conditions between 10 and 20 cm.