Celestia/Celx Scripting/CELX Lua Methods (extraction):
Get the current simulation time as a TDB (Barycentric Dynamical Time) Julian date.
Older Celestia versions use UTC (Coordinated Universal Time) to calculate times and positions.
Starting with version 1.5.0, although Celestia still displays UTC on the screen,
it uses the TDB time scale internally for everything else, so for CELX scripting !!!
The simulation time can be set by using the celestia:settime() method.
To get the current system time instead of the current simulation time, the 1.6.0 celestia:getsystemtime() method should be used instead.
The TDB time scale is a bit different from the more familiar UTC. By using TDB, Celestia places objects much more accurately. As of January 1, 2008, the difference between the two is about 65 seconds. For more information, see Celestia/Time_Scales.
To convert between UTC and TDB times, you can use the 1.5.0 celestia:utctotdb() and 1.5.0 celestia:tdbtoutc() methods.
To convert between normal calender dates and julian days, you can use the celestia:tojulianday() and celestia:fromjulianday() methods.
On the time correction panel (Panel 7), the Julian date was specified in UTC format. In the updated version, the Julian date is specified in TDB format by default.
You can switch readings Julian date [TDB / UTC]