<blockquote><font class="small">In reply to:</font><hr /><p>There was no such information for Mars Polar Lander.<p><hr /></p></p></blockquote><br /><br />Correct. It's still not 100% certain that the root cause was a premature engine cutoff due to an oversensitive touchdown sensor. The way they reached that conclusion was by analysis of the design and testing with spares still on Earth. They found that they could reproduce the hypothesized failure consistently enough to be confident that it would've done MPL in if nothing else went wrong.<br /><br />They tried to do a similar analysis with Beagle 2, but could find nothing so glaringly obvious in the design. In the end, they could reach no conclusions about the cause of the accident, although recent imagery suggests that it might merely have had the rotten luck to land on the side of a steep crater. (That's a calculated risk in any unmanned lander mission, because you simply can't aim the landing accurately enough to avoid all obstacles.)<br /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em> -- The Tenth Doctor, "Blink"</font></p> </div>