Emergency Beacon
Independent Low-Power Distress Transmitter
The emergency beacon, or independent low-power distress transmitter, is a standalone UHF or L-band radio that broadcasts settlement location, time, and survival status directly to Earth when primary communications fail. Housed in hermetically sealed titanium with radiation-hardened electronics, the device utilizes an independent radioisotope or long-life battery power source rated for at least 50 years of operation and a 100-year service life. Operating on the lunar surface requires surviving prolonged lunar nights, decades of unshielded radiation, and extreme temperatures without active thermal control systems. Transmitting at one watt or greater via an omnidirectional antenna at intervals under 60 seconds, it maintains reliable Earth detectability while isolated from external dust intrusion.
Independent low-power distress transmitter that broadcasts the Ark's location and status when primary communication systems are degraded or failed.
Purpose
Ensure the Ark can always be located and its survival status determined, even in worst-case failure scenarios where main power and communications are lost.
Context
Last-resort communication capability with independent power source and minimal dependencies; designed to outlast all other systems and guide future recovery missions.
Principles
- ▸Maximum independence from other Ark systems
- ▸Ultra-low power consumption for decades of operation on backup power
- ▸Simple, robust modulation for reliable detection at Earth
- ▸Encodes minimal but critical information: location, time, status
Typical implementations
- ▸UHF or L-band beacon transmitter
- ▸Radioisotope or long-life battery power source
- ▸Omnidirectional antenna for guaranteed Earth visibility
- ▸Simple FSK or PSK modulation
Lunar considerations
- ▸Must survive worst-case thermal without active thermal control
- ▸Independent power source required for lunar night survival
- ▸Radiation hardening for decades of unshielded exposure
- ▸Dust-resistant sealed enclosure
Specifications
Functional
| primary function | Continuously broadcast distress signal containing Ark location and basic survival status |
| inputs | health status summary from CDH (when available), internal battery/RTG power |
| outputs | RF beacon signal detectable by Earth stations or lunar orbiters |
| transmit power w | >=1 |
| beacon interval s | <=60 |
| detectable at earth | True |
| independent runtime years | >=50 |
Physical
| materials | hermetically sealed titanium housing, radiation-hardened electronics |
| vacuum | True |
| radiation | lunar surface |
| thermal independent | True |
Operational
| thermal range c | -173, 127 |
| lifetime years | 100 |
Interfaces
Provides
- RF beacon detectable by Earth ground stations or lunar orbiters
Requires
- Optional health summary for beacon encoding; beacon operates without it
- Internal RTG or long-life battery independent of main EPS
Decomposes into
Cite this entry
Lunar Ark Codex. "Emergency Beacon" (L2-COM-BEAC). Retrieved 10 September 2026, from https://lunarark.com/entry/L2-COM-BEAC
Licensed CC-BY-SA 4.0. You may reuse and adapt this entry with attribution, under the same licence.