Spherical harmonic analysis of third-order gravitational tensor components and its implications for future gravity-dedicated satellite mission designs
ŠPRLÁK, M., NOVÁK, P., PITOŇÁK, M., HAMÁČKOVÁ, E. Spherical harmonic analysis of third-order gravitational tensor components and its implications for future gravity-dedicated satellite mission designs. Praha, 2015.
|Anglický název:||Spherical harmonic analysis of third-order gravitational tensor components and its implications for future gravity-dedicated satellite mission designs|
|Autoři:||Ing. Michal Šprlák Ph.D. , Prof. Ing. Pavel Novák Ph.D. , Ing. Martin Pitoňák Ph.D. , Ing. Eliška Hamáčková ,|
|Abstrakt EN:||One of the fundamental physical manifestations of the Earth is the gravitational field. Its global representation in the form of a global gravitational model is usually based on spherical harmonic series of the gravitational potential. From such a model any functional of the gravitational potential may be evaluated. Significant improvements in modelling the global gravitational field have recently been made due to new satellite data provided by the gravity-dedicated satellite missions CHAMP, GRACE and GOCE. New global gravitational models have consequently allowed for many applications in geodesy, geophysics, oceanography, glaciology or climatology. Far reaching applications, progress in technology and the need for better understanding of the Earth system stimulates for proposals of future satellite missions. In this study we assume a third-order gravitational tensor would potentially become observable at satellite altitudes. Such a tensor composed of 10 different components may be divided into vertical-vertical-vertical, vertical-vertical-horizontal, vertical-horizontal-horizontal and horizontal-horizontal-horizontal parts. Firstly, we derived new integral formulas between spherical harmonic coefficients of the gravitational potential and the four parts of the third-order gravitational tensor. Secondly, we studied possible improvements of the gravitational field due to observations of the third-order gravitational tensor in a closed-loop simulation. For simplicity, we assume global grids of the corresponding observables are available on a spherical (mean orbital) surface. Sensitivity of the third-order gravitational tensor for the global gravitational field recovery is tested for various orbital altitudes and different levels of the white observation noise.|