Ever since E.Cartan in the 1920s enriched the geometric framework of generalrelativity (GR) by introducing a {\it torsion} of spacetime, the question arosewhether one could find a measurement technique for detecting the presence of atorsion field. Mao et al.(2007) claimed that the rotating quartz balls in thegyroscopes of the Gravity Probe B experiment, falling freely on an orbit aroundthe Earth, should "feel" the torsion. Similarly, March et al.(2011) argue withthe precession of the Moon and the Mercury and extend later theirconsiderations to the Lageos satellite.--- A consistent theory of gravity withtorsion emerged during the early 1960's as gauge theory of the Poincar\'egroup. This Poincar\'e gauge theory of gravity incorporates as simplest viablecases the Einstein-Cartan(-Sciama-Kibble) theory (EC), the teleparallelequivalent GR|| of GR, and GR itself. So far, PG and, in particular, theexistence of torsion have {\it not} been experimentally confirmed. However, PGis to be considered as the standard theory of gravity with torsion because ofits very convincing gauge structure.--- Since the early 1970s up to today,different groups have shown more or less independently that torsion couplesonly to the {\it elementary particle spin} and under no circumstances to theorbital angular momentum of test particles. This is established knowledge andwe reconfirm this conclusion by discussing the energy-momentum law of PG, whichhas same form for all versions of PG. Therefore, we conclude that,unfortunately, the investigations of Mao et al. and March et al. do not yieldany information on torsion.
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