Somigliana equation The above expression for g has been supplanted by the Somigliana equation (after Carlo Somigliana) : where, is the spheroid's eccentricity, squared; is the defined gravity at the equator and poles, respectively; (formula constant);%DIFDELCMD < %DIFDELCMD < %%% For Earth, = 9.7803253359 ms−2; = 9.8321849378 ms−2; k = 0.00193185265241 ; e2 = 0.00669437999013:Department of Defense World Geodetic System 1984 ― Its Definition and Relationships with Local Geodetic Systems, NIMA TR8350.2, 3rd ed. , Tbl. 3.4, Eq. 4-1 Eq. 2.57 in MIT Essentials of Geophysics OpenCourseWare notes
 The above expression for g has been supplanted by the Somigliana equation (after Carlo Somigliana) %DIFDELCMD < %DIFDELCMD < %%% .
D
Somigliana equation
D
:
D
where, is the spheroid's eccentricity, squared; is the defined gravity at the equator and poles, respectively; (formula constant);
R
For Earth, = 9.7803253359 ms−2; = 9.8321849378 ms−2; k = 0.00193185265241 ; e2 = 0.00669437999013:Department of Defense World Geodetic System 1984 ― Its Definition and Relationships with Local Geodetic Systems, NIMA TR8350.2, 3rd ed. , Tbl. 3.4, Eq. 4-1 Eq. 2.57 in MIT Essentials of Geophysics OpenCourseWare notes
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