From the January 2003 issue

What could’ve been

Had NASA's Mars Polar Lander successfully landed and completed its mission objectives, our understanding of the Red Planet's climate would have dramatically increased.
By | Published: January 7, 2003 | Last updated on May 18, 2023
deep space 2 probe
As with the Polar Lander, these probes failed to respond to communication efforts.
JPL
mars polar lander
After a 10-month journey, the Polar Lander was to land and survey the climate and search for the possibility of water on Mars.
JPL
South Pole Neutron Map
The Mars Odyssey spacecraft constructed this look at the Red Planet’s south pole. It shows the presence of intermediate-energy, or epithermal, neutrons. Low levels of epithermal neutrons reveal hydrogen-enriched soil. Planetary scientists believe much of the hydrogen detected there is bound in water ice.
NASA / JPL / University of Arizona
The Mars Odyssey spacecraft constructed this look at the Red Planet’s south pole. It shows the presence of intermediate-energy, or epithermal, neutrons. Low levels of epithermal neutrons reveal hydrogen-enriched soil. Planetary scientists believe much of the hydrogen detected there is bound in water ice.
NASA / JPL / University of Arizona
Since Mariner 4 closely swept by Mars in 1965, unmanned probes have contributed greatly to our knowledge of the Red Planet. Martian studies have shifted to searching for water and subsequently the possibility of life on the planet. As an unprecedented decade of sending probes to Mars drew to a close, NASA launched a spacecraft to land on the planet’s surface. Unfortunately, the Mars Polar Lander mysteriously disappeared during its scheduled landing on December 3, 1999.

Unlike any previous or planned Mars mission, the probe was to touch down at the planet’s south pole. A tenth of the size of its northern counterpart, the south pole’s permanent cap is thought to be mostly carbon dioxide and possibly water. A seasonal cap expands on the south pole during the winter, when Mars is at its furthest point from the sun. With the fluctuating caps and suspected atypically layered terrain, this was an optimum location to survey martian climate and search for water.

Approximately 10 minutes before landing, Mars Polar Lander was to drop two Deep Space 2 microprobes. The projectiles were to collect atmospheric data before crashing and burying themselves beneath the martian surface. Had these microprobes been successfully dropped, the instruments would have also collected and heated soil to scan for vaporized water ice.

During its final approach, Mars Polar Lander was to photograph the terrain of the south pole and surrounding areas. Continuing the imaging after the landing, the Surface Stereo Imager, using various color filters, was to capture more photographs to help determine soil types and soil composition.

While on the ground, Mars Polar Lander would have used its robotic arm to dig a hole in the terrain. The soil removed in this process would be heated and analyzed for water, like the soil collected by the microprobes. In the meantime, the probe’s camera would photograph the exposed terrain, searching for fine-scale layering.

Collaborative instruments from the Planetary Society in Pasadena and Russia’s Space Research Institute were to exercise the climatic studies. A light detection device was to determine the altitude of dust and ice clouds hanging over the lander. A small microphone on board would capture the sounds of wind gusts, blowing dust, and the spacecraft itself.

Had Mars Polar Lander survived, it would have operated for 60 to 90 days during Mars’s southern summer. Eventually the probe would have failed as it succumbed to the cold and darkness as the nights grew longer.