IVS EOP Format, Version 2.1 (last updated: 2009-01-12)
File names ending with
.eops contain nutation offsets in dpsi, deps w.r.t.
the IAU1980 nutation model while file names ending with
.eoxy contain nutation
offsets in dX, dY w.r.t. the IAU2006 nutation model (the model should exclude
free core nutation).
Files are free format with fields separated by at least one blank.
|1||MJD of the measurement (with at least 5 decimal digits)|
|2||x of the pole (arcseconds)|
|3||y of the pole (arcseconds)|
|5||dpsi or dX (milliarcseconds)|
|6||deps or dY (milliarcseconds)|
|Uncertainty of Earth Orientation and Nutation|
|7||uncertainty in x (arcseconds)|
|8||uncertainty in y (arcseconds)|
|9||uncertainty in UT1-UTC (seconds)|
|10||uncertainty in dpsi or dX (milliarcseconds)|
|11||uncertainty in deps or dY (milliarcseconds)|
|12||wrms residual delay of the session in ps (preferably integer)|
|13||correlation coefficient: x, y|
|14||correlation coefficient: x, UT1|
|15||correlation coefficient: y, UT1|
|16||correlation coefficient: dpsi/deps or dX/dY|
|17||number of observables|
|18||6 character session code according to the 2nd column of IVS master schedules, e.g for 2020: master20.txt|
|19||span of the observation (in hours)|
|Rates of Earth Orientation and Nutation|
|20||x rate of the pole (arcseconds/day)|
|21||y rate of the pole (arcseconds/day)|
|22||excess length of day (LOD) (seconds), see comment below|
|23||dpsi rate (milliarcseconds/day)|
|24||deps rate (milliarcseconds/day)|
|Uncertainty of Rates of Earth Orientation and Nutation|
|25||uncertainty in x rate (arcseconds/day)|
|26||uncertainty in y rate (arcseconds/day)|
|27||uncertainty in LOD (s)|
|28||uncertainty in dpsi rate (milliarcseconds/day)|
|29||uncertainty in deps rate (milliarcseconds/day)|
|Configuration of network employed for these Results|
|30||sequence of two-character IVS station identifiers as maintained
in IVS master control file ns-codes.txt (no blanks between stations)
- For the EOP rates, days are in 86400 SI seconds.
- The lines starting with characters "
! # or *" are considered as comments.
- Although it is inconsistent to have LOD in the group of rates due to the toggling of the sign, it is maintained here for consistency with other space techniques.
LOD = UT1(n) - UT1(n+1) with n in days. LOD has the same magnitude but opposite sign of the UT1-UTC rate or the UT1-TAI rate, which are normally determined in VLBI analyses and given in seconds/day.