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Earth Orientation Transition to TechNote36 Notice!!!

Starting on 14 June 2016 - EOPPyddd (6166), the NGA Earth Orientation Parameter Predictions (EOPP) is scheduled to switch to the IERS Technical Note 36/IERS Conventions (2010) (TN36). This is covered in TN36/Chapter 8. The NGA EOPP will use the Gross zonal tide model along with the Oceans diurnal/semidiurnal model. The TN36 will restore the full 62 Gross zonal tide model.

With this transition, NGA will continue to produce the older TechNote21 version with the 41-zonal tide model, BUT WILL NOT place on the 'ftp/web' sites. This will only be used as a 'contingency' backup to Air Force. This also includes producing the 41-zonal tide approximation model.

NGA transitioned to the full 62 Gross zonal tide model on 14 June 2016 (6166).

Any questions, please use the contact information below.

Point of Contact: NGA Public Affairs
Phone Numbers:
  Com. (571)557-5400
  DSN 846-9140

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