Details
| Original language | English |
|---|---|
| Pages (from-to) | 385-396 |
| Number of pages | 12 |
| Journal | Advances in space research |
| Volume | 50 |
| Issue number | 3 |
| Publication status | Published - 1 Aug 2012 |
Abstract
The restricted sensitivity of the Gravity field and steady-state Ocean Circulation Explorer (GOCE) gradiometer instrument requires satellite gravity gradiometry to be supplemented by orbit analysis in order to resolve long-wavelength features of the geopotential. For the hitherto published releases of the GOCE time-wise (TIM) and GOCE space-wise gravity field series - two of the official ESA products - the energy conservation method has been adopted to exploit GPS-based satellite-to-satellite tracking information. On the other hand, gravity field recovery from data collected by the CHAllenging Mini-satellite Payload (CHAMP) satellite showed the energy conservation principle to be a sub-optimal choice. For this reason, we propose to estimate the low-frequency part of the gravity field by the point-wise solution of Newton's equation of motion, also known as the acceleration approach. This approach balances the gravitational vector with satellite accelerations, and hence is characterized by (second-order) numerical differentiation of the kinematic orbit. In order to apply the method to GOCE, we present tailored processing strategies with regard to low-pass filtering, variance-covariance information handling, and robust parameter estimation. By comparison of our GIWF solutions (initials GI for "Geodätisches Institut" and IWF for "Institut für WeltraumForschung") and the GOCE-TIM estimates with a state-of-the-art gravity field solution derived from GRACE (Gravity Recovery And Climate Experiment), we conclude that the acceleration approach is better suited for GOCE-only gravity field determination as opposed to the energy conservation method.
Keywords
- Empirical covariance function, GOCE, GPS, Gravity field, Kinematic positions, Numerical differentiation
ASJC Scopus subject areas
- Engineering(all)
- Aerospace Engineering
- Physics and Astronomy(all)
- Astronomy and Astrophysics
- Earth and Planetary Sciences(all)
- Geophysics
- Earth and Planetary Sciences(all)
- Atmospheric Science
- Earth and Planetary Sciences(all)
- Space and Planetary Science
- Earth and Planetary Sciences(all)
Sustainable Development Goals
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In: Advances in space research, Vol. 50, No. 3, 01.08.2012, p. 385-396.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - GOCE orbit analysis
T2 - Long-wavelength gravity field determination using the acceleration approach
AU - Baur, O.
AU - Reubelt, T.
AU - Weigelt, M.
AU - Roth, M.
AU - Sneeuw, N.
PY - 2012/8/1
Y1 - 2012/8/1
N2 - The restricted sensitivity of the Gravity field and steady-state Ocean Circulation Explorer (GOCE) gradiometer instrument requires satellite gravity gradiometry to be supplemented by orbit analysis in order to resolve long-wavelength features of the geopotential. For the hitherto published releases of the GOCE time-wise (TIM) and GOCE space-wise gravity field series - two of the official ESA products - the energy conservation method has been adopted to exploit GPS-based satellite-to-satellite tracking information. On the other hand, gravity field recovery from data collected by the CHAllenging Mini-satellite Payload (CHAMP) satellite showed the energy conservation principle to be a sub-optimal choice. For this reason, we propose to estimate the low-frequency part of the gravity field by the point-wise solution of Newton's equation of motion, also known as the acceleration approach. This approach balances the gravitational vector with satellite accelerations, and hence is characterized by (second-order) numerical differentiation of the kinematic orbit. In order to apply the method to GOCE, we present tailored processing strategies with regard to low-pass filtering, variance-covariance information handling, and robust parameter estimation. By comparison of our GIWF solutions (initials GI for "Geodätisches Institut" and IWF for "Institut für WeltraumForschung") and the GOCE-TIM estimates with a state-of-the-art gravity field solution derived from GRACE (Gravity Recovery And Climate Experiment), we conclude that the acceleration approach is better suited for GOCE-only gravity field determination as opposed to the energy conservation method.
AB - The restricted sensitivity of the Gravity field and steady-state Ocean Circulation Explorer (GOCE) gradiometer instrument requires satellite gravity gradiometry to be supplemented by orbit analysis in order to resolve long-wavelength features of the geopotential. For the hitherto published releases of the GOCE time-wise (TIM) and GOCE space-wise gravity field series - two of the official ESA products - the energy conservation method has been adopted to exploit GPS-based satellite-to-satellite tracking information. On the other hand, gravity field recovery from data collected by the CHAllenging Mini-satellite Payload (CHAMP) satellite showed the energy conservation principle to be a sub-optimal choice. For this reason, we propose to estimate the low-frequency part of the gravity field by the point-wise solution of Newton's equation of motion, also known as the acceleration approach. This approach balances the gravitational vector with satellite accelerations, and hence is characterized by (second-order) numerical differentiation of the kinematic orbit. In order to apply the method to GOCE, we present tailored processing strategies with regard to low-pass filtering, variance-covariance information handling, and robust parameter estimation. By comparison of our GIWF solutions (initials GI for "Geodätisches Institut" and IWF for "Institut für WeltraumForschung") and the GOCE-TIM estimates with a state-of-the-art gravity field solution derived from GRACE (Gravity Recovery And Climate Experiment), we conclude that the acceleration approach is better suited for GOCE-only gravity field determination as opposed to the energy conservation method.
KW - Empirical covariance function
KW - GOCE
KW - GPS
KW - Gravity field
KW - Kinematic positions
KW - Numerical differentiation
UR - http://www.scopus.com/inward/record.url?scp=84862174824&partnerID=8YFLogxK
U2 - 10.1016/j.asr.2012.04.022
DO - 10.1016/j.asr.2012.04.022
M3 - Article
AN - SCOPUS:84862174824
VL - 50
SP - 385
EP - 396
JO - Advances in space research
JF - Advances in space research
SN - 0273-1177
IS - 3
ER -