Fe b 20 07 A comment on the paper “ On the orbit of the LARES satellite ”

In this note we comment on a recent paper by I.Ciufolini about the possibility of placing the proposed terrestrial satellite LARES in a lowaltitude, nearly polar orbit in order to measure the general relativistic Lense-Thirring effect with its node. Ciufolini claims that, for a departure of 4 deg in the satellite’s inclination i from the ideal polar configuration (i = 90 deg), the impact of the errors in the even zonal harmonics of the geopotential, modelled with EIGEN-GRACE02S, would be nearly zero allowing for a few-percent measurement of the LenseThirring effect. Instead, we find that, with the same Earth gravity model and for the same values of the inclination, the upper bound of the systematic error due to the mismodelling in the even zonals amounts to 64% of the relativistic effect investigated.