6h 57min, dec 11, 1998 y - Mars Climate Orbiter
Failed Mars orbiter (NASA)
Mars Climate Orbiter was lost on September 23, 1999, when a mathematical conversion error placed the spacecraft too close to Mars at the time of orbital insertion. Mars Climate Orbiter carried a few re-flown instruments from Mars Observer, marking the second failures for those experiments.
Added to timeline:
the videos are in the parts of Mars Exploration Rover Spirit...