Monthly mean of degree 1 from SLR (CSR RL06) for details see http://ifg.tugraz.at/downloads/gravity-field-models/itsg-grace2018 begin_of_head ======================================== modelname model_degree1_2009-01 product_type gravity_field earth_gravity_constant 3.9860044150e+14 radius 6.3781363000e+06 max_degree 1 norm fully_normalized errors no key L M C S end_of_head ========================================== gfc 0 0 0.000000000000e+00 0.000000000000e+00 gfc 1 0 1.119826884301e-10 0.000000000000e+00 gfc 1 1 -1.402076264473e-12 -3.654462114417e-10