Solid Tides File

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The Solid Tides Love Number file (IERS2003.dat, GRAIL2013.dat) contains data used for modeling a central body's solid-tides induced by perturbing bodies. For the Earth's file, IERS2003.dat, the data is taken from the IERS Technical Note 32, published in 2003, while the Lunar Solid Tides File, GRAIL2013.dat, uses data taken from the GRAIL primary mission, published in 2013. This data primarily consists of the Love Numbers up to Degree and Order 3 for the Earth, and 2 for the Moon. Additionally, the file contains the H0 coefficient used for modeling the Permanent Tide contribution. The value for A0 is calculated internally based on the central body, and no longer needs to be specified within this file. These coefficients are used in conjunction with a Tide-Free geopotential, such as the EGM-96. The other geopotential files included with FreeFlyer (JGM-2, GGMO2C) are Zero-Tide models, and already have the Permanent Tide contribution included in the J2 term.

 

The format of the file is shown below. Note that the H0 coefficient's value is optional, and will be replaced with a 0 if not present. It is important that a placeholder, such as a dash, be inserted to ensure proper parser functionality in the event of a missing H0 value.

 

Solid Earth Tide external Love numbers taken from IERS Conventions (2003)

Central Body    Deg    Ord        H0

  EARTH        003    003     -0.31460  

 

      Deg  Ord     Knm

LNUM    2    0    0.30190

LNUM    2    1    0.29830

LNUM    2    2    0.30102

LNUM    3    0    0.09300

LNUM    3    1    0.09300

LNUM    3    2    0.09300

LNUM    3    3    0.09400

Solid Lunar Tide external Love numbers taken from GRAIL Primary Mission Data (2013)

Central Body    Deg    Ord        H0

  MOON        002    002         -  

 

      Deg  Ord     Knm

LNUM    2    0    0.02408

LNUM    2    1    0.02414

LNUM    2    2    0.02394