AT (After Tranquility)
AT (also A.T. or a.t.): After Tranquillity. Any date after the first landing of Terragens on another celestial body, when the Apollo 11 mission achieved touchdown on the Old Earth's Moon. This was July 20, 1969 c.e. or AD in the Gregorian calendar, and Armstrong Day, 0 AT in the later Tranquillity Calendar that became standard in Solsys during the First Federation era.

The Tranquility Calendar mapped to the Gregorian

Tranquility Calendar 2
Image from Steve Bowers
Click for Larger Image

 
Related Articles
 
Appears in Topics
 
Development Notes
Text by Stephen Inniss

Initially published on 29 September 2009.