AU-8 - Time Stamps

a. Use internal system clocks to generate time stamps for audit records; and b. Record time stamps for audit records that meet [Assignment: organization-defined granularity of time measurement] and that use Coordinated Universal Time, have a fixed local time offset from Coordinated Universal Time, or that include the local time offset as part of the time stamp.


ID: AU-8
Enhancements: 

Space Segment Guidance

Precise and consistent time stamps are essential in a space environment, where spacecraft typically rely on external timing sources (e.g., GPS signals or ground-station references).  Accurate event logging supports anomaly investigations, forensics, and synchronizing distributed constellations.  If multiple payloads share the same bus, ensuring each subsystem’s clocks remain aligned is critical for correlating telemetry and detecting suspicious behavior.  In practice, mission operators often collect raw time data from the spacecraft, cross-check it against a known authoritative clock on the ground, and incorporate any necessary corrections in the final log.  This approach yields consistent logs while minimizing on-board processing overhead.