Scene Context: After the Martian orbital network is destroyed, the crew concludes that without the deployable relay in Sector 4-B, the landing will be almost completely blind.
Essence of the Phenomenon: This is no longer new physics, but the rigid engineering logic of systems. If the primary navigation and relay network is destroyed, the value of any pre-planned autonomous communication and telemetry node skyrockets.
Scientific Basis: Orbital relays are a real critical part of Mars communications architecture. They transmit commands from Earth, receive surface data, and provide a much better channel than direct-to-Earth communication from a lander.
Current Limitations: A backup relay does not automatically "solve" the crisis. Its value depends on whether it is functional, has enough power, reaches the required communications geometry, and can operate autonomously without full support from the primary network.