Fresh on the successes of the 1997 Pathfinder mission, landing America’s first rover on the rocky Martian expanse of Chryse Planitia, NASA was set for a program designed to study more of the Martian climate, weather and any water to be found.
But Mars has always been an intolerant host for most of the robotic guests that attempt to visit the planet. NASA’s “Faster-Better-Cheaper” philosophy to space mission design, rather than simplifying mission complexity and reducing cost, led the space agency and the contractors that built the spacecraft to make several expensive blunders.
One “cheaper” part of the Mars Climate Orbiter was to use aerobraking to place the spacecraft into a suitable orbit, rather than carrying along heavier reserves of fuel. That’s not a bad plan. However, NASA neglected to spend a few cents on some stamps or phone calls to the spacecraft’s manufacturer, Lockheed Martin, to remind them to stick to the same measurement standards as the agency used.
As the probe neared orbital insertion, the navigation team believed their path was a little lower than expected. They calculated 150 to 170 km (93 to 106 mi) high as the probe went around the planet, and later perhaps as low as 110 km.
Turns out the path was around 57 kilometers, and into much thicker atmosphere. The Mars Climate Orbiter didn’t surf as much as it dived, obliterating itself.
The investigation of the probe’s loss revealed that Lockheed’s team used American Imperial measurements (pounds/force) and not the JPL metric standard (newtons/force). So thruster firings weren’t going by the metric system and inaccuracies crept in the trajectory. A few people noticed the issue but were ignored.
Two and one half months later, the orbiter’s sister spacecraft, the Mars Polar Lander, comes rushing in.
As the probe entered the atmosphere, communications were soon lost entirely, and the probe is believed to have contributed to the Martian crater aesthetic.
The loss of the Polar Lander was likely more of a mechanical goof. Several possible causes of the lander’s loss were noted, but the strongest involved a software glitch in the landing instrumentation.
As the probe entered, the landing legs deployed, causing sufficient vibrations through the spacecraft which were picked up by instruments controlling the descent landing engines. The instruments mistakenly interpreted the landing leg deployment as touchdown, and turned off the engines while the lander was about 40 meters (131 feet) above the Martian surface. The probe becomes an unintended core sampling mission.
While other satellites like the Mars Global Surveyor and Mars Reconnaissance Orbiter have been successful in taking photos of other landers (or their remains) over the years (a recent success was locating the Beagle 2 lander, which went silent after landing on Christmas, 2003), so far there has been no luck in locating the Polar Lander’s wreckage.
“Better-cheaper-faster” seems only justified if success comes from the idea, at least with these two probes.
But JPL and its contractors would soon get back into a very good groove by 2004 with the successful landings of the two Mars Exploration Rovers Spirit and Opportunity. Over twelve years after landing, Opportunity is still exploring, with Spirit succumbing to the elements in 2010.
The mission of the Polar Lander would be picked up and completed with the Mars Phoenix Lander by 2008.
By 2012, JPL makes an incredibly complex landing of the Fiat car-sized Mars Science Laboratory Curiosity, which, among its notable science discoveries, doubles as the coolest (and only) interplanetary selfie camera.