"Relative Earth Space Time, just made that up but sounds cool"
- Unknown source
Each individual world has its own calendar and clock; dependant on the seasons, culture, and length of the local day. The "Spacer Calendar" or "R.E.S.T calendar", is the calendar and clock commonly used by people for whom tracking time based on a single world is too restrictive. It is constantly in use by spacers, interplanetary travellers, and by worlds with any kind of interplanetary presence.
It's worth noting that the Spacer Calendar is notoriously hard to keep exact, as even with gravtech a small amount of space-time dilation still occurs whenever any kind of spike-drive travel is employed, especially spike drills. This most often desyncs travellers' times by hours or minutes, but every seasoned spacer has "lost a day" at some point following a long journey. A system's
comm bouy network will usually keep the 'correct' time, and synchronise any ships that maintain the usual handshake connection with it.
Despite this inaccuracy, without a common way of keeping approximate time, interplanetary and interstellar relations would crumble.
History
The acronym R.E.S.T. is a term lifted from Mandate archives, found throughout the sector particularly around the Core and Amberspace clusters. It is how the Terran Mandate tracked time, and by all accounts it was they who brought the calendar to the sector - and the Exchange which popularised its use post-Scream.
It is unknown exactly what the acronym stands for, but the most commonly accepted is "Relative Earth Space Time", as it's believed that the spacer calendar closely resembles one commonly used on the lost human homeworld of Earth. This is corroborated by the fact that most people are able to adjust to a spacer calendar's day/night cycle with relative ease - regardless of any cycles they might have been accustomed to on other worlds.
