The Lingering Anomalous Secular Increase of the Eccentricity of the Orbit of the Moon: Further Attempts of Explanations of Cosmological Origin

Abstract

A new analysis of extended data records collected with the Lunar Laser Ranging (LLR) technique performed with improved tidal models was not able to resolve the issue of the anomalous rateė of the eccentricity e of the orbit of the Moon, which is still in place with a magnitude ofė = (5 ± 2) × 10 −12 yr −1 . Some possible cosmological explanations are offered in terms of the post-Newtonian effects of the cosmological expansion, and of the slow temporal variation of the relative acceleration rateSS −1 of the cosmic scale factor S. None of them is successful since their predicted secular rates of the lunar eccentricity are too small by several orders of magnitude.

Anomalous accelerations in spacecraft flybys of the Earth

“…This anomaly has not been totally explained with improved models, although the discrepancy among the models and the observations has been slightly reduced to the presently accepted value of de/dt ≃ 3 × 10 −12 yr −1 [80]. Explanations in terms of modified gravity models have been proposed by Iorio [39,38,42].…”

On a correlation among azimuthal velocities and the flyby anomaly sign

“…We have, for example: (a) possible anomalous advances of planetary perihelia (beyond the predictions of GR) as discussed in some studies (Iorio, 2009a; Pitjeva & Pitjev, 2013; Pitjev & Pitjeva, 2013), (b) the lingering unexplained secular increase of the eccentricity of the orbit of the Moon (Iorio, 2011a, 2011b, 2014a; Williams & Boggs, 2009; Williams, Boggs, & Folkner, 2008; Williams, Turyshev, & Boggs, 2014), (c) the so‐called “Faint Young Sun Paradox”, that is, the predictions from models of stellar evolution of a smaller energy output from the Sun in the Archean period than the one necessary to keep Earth's oceans in liquid state (Iorio, 2013; Sagan & Mullen, 1972), (d) the anomalous secular increase of the astronomical unit (Kaplan et al, 2015; Krasinsky & Brumberg, 2004; Standish, 2005), (e) a possible discrepancy between the predicted values of the Sun's angular momentum and its value constrained from planetary dynamics (Iorio, 2007a, 2012a), and (f) an anomalous Doppler blue shift for the Pioneer 10 and 11 spacecrafts corresponding to a constant acceleration a P =(8.74±1.33)×10 −8 cm s −2 , commonly known as the Pioneer anomaly (Anderson et al, 2002; Bertolami, Francisco, Gil, & Páramos, 2008, 2010; Fienga et al, 2010; Francisco, Bertolami, Gil, & Páramos, 2012; Iorio, 2007b, 2010, 2012b; Iorio & Giudice, 2006; Standish, 2008; Tangen, 2007; Turyshev & Toth, 2010; Turyshev et al, 2012).…”

On the secular recession of the Earth-Moon system as an azimuthal gravitational phenomenon

“…The Lunar eccentricity e moon is known to increase at a rate such that [ė moon = (5.00 ± 2.00) × 10 −12 yr −1 ] (Williams et al 2014). As already said, this increase in the eccentricity is assumed by some researchers (Iorio 2011a(Iorio , 2014b(Iorio , 2015Riofrio 2012;Ziefle 2013;Acedo 2014) to be divorced from the Lunar drift. Against this line of thinking, it has been argued in reading Nyambuya (2015a) that these two phenomenon (i.e.…”

“…Iorio 2011b). Researchers (Williams et al 2004;Iorio 2011aIorio , 2011bIorio , 2014bXin 2011;Riofrio 2012;Acedo 2013aAcedo , 2013bZiefle 2013;Nyambuya 2014e) have proposed various mechanisms to explain this seemingly observation.…”

“…Iorio 2011aIorio , 2014bIorio , 2015Riofrio 2012;Ziefle 2013;Acedo 2014). The Lunar eccentricity e moon is known to increase at a rate such that [ė moon = (5.00 ± 2.00) × 10 −12 yr −1 ] (Williams et al 2014).…”