ITelescopeV3SiderealTime Property
The local apparent sidereal time from the telescope's internal clock (hours, sidereal)

Namespace: ASCOM.DeviceInterface
Assembly: ASCOM.DeviceInterfaces (in ASCOM.DeviceInterfaces.dll) Version: 6.0.0.0 (6.2.0.2774)
Syntax
double SiderealTime { get; }

Property Value

Type: Double
Remarks

Must be implemented, must not throw a PropertyNotImplementedException.

It is required for a driver to calculate this from the system clock if the telescope has no accessible source of sidereal time. Local Apparent Sidereal Time is the sidereal time used for pointing telescopes, and thus must be calculated from the Greenwich Mean Sidereal time, longitude, nutation in longitude and true ecliptic obliquity.
See Also