What is MCT
Mars Civil Time (MCT) is a proposed civil time for Mars settlements, defined relative to the mean solar time at the IAU prime meridian (AMT).
MCT = wrap24(AMT + 2h)
MCT is not a separate realization of MRT (Mars Reference Time) — it is a civil layer built on top of AMT. See /definition for the full layered framework.
Offsets from other regions
| Region | Longitude | Offset from MCT | Status |
|---|---|---|---|
| Arabia Terra | 30°E | +00:00 | Proposed origin |
| Hellas Planitia | 70°E | +02:40 | Research example |
| Tharsis | 100°W | −08:40 | Research example |
| Valles Marineris | 60°W | −06:00 | Research example |
Greenwich stays in the narrative
Arabia Terra is the proposed civil time origin for future Mars settlements, while the IAU prime meridian remains the scientific and navigational longitude origin.