  The neoclassical causal version for Newton's acausal gravitational theory
explains exactly the anomalous speed-changes observed for six Earth flybys and
an anomalous lunar orbital speed-change (arXiv:1105.3857v10). This article
estimates the effects of the neoclassical causal theory on the orbital motions
of two objects revolving around the Sun, Mercury and Halley's Comet. The change
in the period for Mercury is predicted to be about +1.86 ms per year, and the
predicted change in the angle for perihelion is -0.032 arc seconds per century,
for which the magnitude is negligible compared with the relativistic advance of
+43 arc seconds per century. The period for Halley's Comet, 75.3 years, is
predicted to decrease by about 10 minutes. Therefore, the neoclassical causal
theory does not conflict with general relativity theory, and it is not the
cause for a delay of one or two weeks in the return time of Halley's Comet.
