The Effects of the IERS Conventions (2010) on High Precision Orbit Propagation
The Earth is not perfectly spherical and its rotational axis is not fixed in space, and these geophysical and kinematic irregularities work as dominant perturbations in satellite orbit propagation. The International Earth Rotation Service (IERS) provides the Conventions as guidelines for using the...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
The Korean Space Science Society
2014-03-01
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| Series: | Journal of Astronomy and Space Sciences |
| Subjects: | |
| Online Access: | http://ocean.kisti.re.kr/downfile/volume/kosss/OJOOBS/2014/v31n1/OJOOBS_2014_v31n1_41.pdf |
| Summary: | The Earth is not perfectly spherical and its rotational axis is not fixed in space, and these geophysical and kinematic
irregularities work as dominant perturbations in satellite orbit propagation. The International Earth Rotation Service (IERS)
provides the Conventions as guidelines for using the Earth’s model and the reference time and coordinate systems defined
by the International Astronomical Union (IAU). These guidelines are directly applied to model orbital dynamics of Earth
satellites. In the present work, the effects of the latest conventions released in 2010 on orbit propagation are investigated by
comparison with cases of applying the previous guidelines, IERS Conventions (2003). All seven major updates are tested, i.e.,
for the models of the precession/nutation, the geopotential, the ocean tides, the ocean pole tides, the free core nutation, the
polar motion, and the solar system ephemeris. The resultant position differences for one week of orbit propagation range
from tens of meters for the geopotential model change from EGM96 to EGM2008 to a few mm for the precession/nutation
model change from IAU2000 to IAU2006. The along-track differences vary secularly while the cross-track components show
periodic variation. However, the radial-track position differences are very small compared with the other components in
all cases. These phenomena reflect the variation of the ascending node and the argument of latitude. The reason is that the
changed models tested in the current study can be regarded as small fluctuations of the geopotential model from the point
of view of orbital dynamics. The ascending node and the argument of latitude are more sensitive to the geopotential than the
other elements. This study contributes to understanding of the relation between the Earth’s geophysical properties and orbital
motion of satellites as well as satellite-based observations. |
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| ISSN: | 2093-5587 2093-1409 |