curacies.
The observations of the star sensor providing absolute atti-
tude information are necessary for single strip adjustment
without GCP, but dispensable for single strips with GCP
and for blocks.
6 SUMMARY AND OUTLOOK
The reconstruction of the image orientation of the MOMS-
02 camera is based on a combined adjustment of the com-
plete image, ground control, orbit and attitude informa-
tion. To this end, the conventional bundle adjustment
algorithm is supplemented by a rigorous dynamical mod-
eling of the spacecraft motion to take orbital constraints
into account.
The results of the combined adjustment using MOMS-
02/D2 imagery and control information of orbit #75B are
presented. About 14000 conjugate points in one imag-
ing sequence covering 430x37 km? were processed together
with the epoch state vector, IMU data and 12 GPS-derived
GCP. Within the threefold overlapping area an empirical
accuracy of 12m (0.9 pixel) in planimetry and 7m (0.5
pixel) in height was achieved as verified by 63 indepen-
dent check points.
Computer simulations on MOMS-2P image orientation
and point determination based on realistic input informa-
tion have shown that the accuracies of the estimated ex-
terior orientation parameters and object point coordinates
will be insufficient, if single strips are processed without
any ground control, due to the poor absolute attitude in-
formation. Good accuracies, in constrast, can be obtained
either with a few precise GCP or even without ground
control information, if a block of several overlapping strips
with high geometric strength (q = 60%) is adjusted.
Further computer simulations on MOMS-2P image orien-
tation will be performed to analyze the influence of the
number of conjugate points and of the accuracy of the
interior orientation parameters on the final results. More-
over, the role of the orbit and attitude observations with
their relative and absolute accuracies will be investigated
in more detail.
7 ACKNOWLEDGEMENT
The work presented in this paper is funded by grants
50 QS 9008 and 50 QM 9205 of the German Space Agency
(DARA).
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164
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