- Calculates the difference between universal time and dynamical time (TT - UT1) following Richard Ray's PERTH3 algorithms
from pyTMD.calc_delta_time import calc_delta_time
deltat = calc_delta_time(delta_file, iMJD)
delta_file
:- http://maia.usno.navy.mil/ser7/deltat.data
- ftp://cddis.nasa.gov/products/iers/deltat.data
iMJD
: Modified Julian Day of times to interpolate
deltat
: (TT - UT1) in days