palDt

Estimate the offset between dynamical time and UT

Description:

Estimate the offset between dynamical time and Universal Time for a given historical epoch.

Invocation

double palDt( double epoch );

Arguments

epoch = double (Given)
Julian epoch (e.g. 1850.0)

Returned Value

palDt = double
Rough estimate of ET-UT (after 1984, TT-UT) at the given epoch, in seconds.

Notes:

before 979 Stephenson & Morrison s 390 BC to AD 948 model 979 to 1708 Stephenson & Morrison s 948 to 1600 model after 1708 McCarthy & Babcock s post-1650 model

The breakpoints are chosen to ensure continuity: they occur at places where the adjacent models give the same answer as each other.

See Also

Explanatory Supplement to the Astronomical Almanac, ed P.K.Seidelmann, University Science Books (1992), section 2.553, p83. This contains references to the Stephenson & Morrison and McCarthy & Babcock papers.