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Originally Posted by Jerry
If you happen to have the descent profile for the Spirit and Opportunity missions, I would appreciate those as well, because to the best of my knowledge, NASA has never released them.
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Really?
I posted the
Mars Exploration Rovers Entry, Descent, and Landing Trajectory Analysis last week. This document shows the predicted EDL values and the actual values they've been able to reconstruct so far.
There are 16 reconstructed values for Spirit, of which only 1 value was outside the predicted range. There are 15 reconstructed values for Opportunity, of which 3 were out of range. Two of those three were only slightly over predicted.
Here is what the authors say:
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Also listed in Tables 3 and 4 are the trajectory conditions reconstructed thus far from the actual “Spirit” and
“Opportunity” flight data obtained during their respective landings. The reconstruction effort is still ongoing, however,
preliminary reconstruction results are shown for comparison to the pre-entry predictions. Accelerometer and
gyro flight data were recorded during both descents and the parameters that can be reconstructed from this data set
are listed. As seen, almost all the reconstructed parameters are well within the pre-entry predicted 3-σ variations.
However, there are a few parameters that are near or slightly exceed the 3-σ variation bounds (e. g., time of and αT
at parachute deployment).
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Further on:
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The landing locations for both “Spirit” and “Opportunity” were within the pre-entry predicted footprint ellipses.
“Spirit” landed 13.4 km downrange from its predicted landing location, while “Opportunity landed 14.9 km downrange
from its predicted landing location. The reconstruction work is ongoing in order to gain a better understanding
of what transpired during the “Spirit” and “Opportunity” landings.
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