Five astronauts are stranded on Mars. Their only hope is to find the vehicle of an earlier crew who died—but that ship is at the north pole and they’re south of the equator. And so they trek north across Mars. They know that the other ship can’t hold them all, and some of them start dying along the way.
Landis is a NASA scientist who writes “hard science fiction”; i.e., SF that’s solidly based in science, some of which is known for plodding writing and dull characters. Landis’s characters have some depth but they’re not that interesting.