palDtt palDtt - Return offset between UTC and TT

Description:
Increment to be applied to Coordinated Universal Time UTC to give Terrestrial Time TT (formerly Ephemeris Time ET)

Invocation:
dtt = palDtt( double utc );

Arguments:

utc = double (Given)
UTC date as a modified JD (JD-2400000.5)

Returned Value:

dtt = double
TT-UTC in seconds

Notes: