{"module":"daylight","engine":"AVWARE astronomical civil-twilight calculator","definition":{"first_light":"beginning of morning civil twilight","last_light":"end of evening civil twilight","civil_twilight_solar_elevation_deg":-6.0},"capabilities":["airport first light","airport last light","sunrise and sunset","UTC output","arbitrary latitude/longitude calculation"],"time_standard":"UTC","operational_use":"planning aid; verify with approved/operator-authorised sources where required"}