ESTELA is a C library to compute the locations of objects in the sky in the frame of reference of an observer on Earth.
- Date & time calculations with
estela_datetime_t, supporting years from 0000 to 9999, microsecond precision, and including conversions to/from Julian date and UNIX time. - Time arithmetic of datetimes with
estela_timedelta_t, including adding, subtracting, multiplication, division, and modulus between timedeltas; multiplication, division, and modulus between timedelta and an integer; and adding and subtracting a timedelta from a datetime.