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This paper addresses several issues concerning Milankovitch Theory and its relationship to paleoclimate data over the last 800,000 years. A model is presented that deconvolutes the precession index (precession modulated by the eccentricity) and the obliquity contributions to the percentage change between successive mean-daily-insolation minima and maxima. The sum of these contributions is in close agreement with the corresponding benchmark calculation of J. Laskar et al. The model predictions indicate that the precession index contribution dominates such insolation changes, and its time-dependent behavior correlates with the occurrence of interglacial and glacial periods and temperature trends during these periods. Best fit curves to the separate contributions appear as quasiperiodic waves that correlate with interglacial initiations and terminations through their constructive and destructive interference. However, a comparison of model predictions with the EPICA Dome C (EDC) data indicates delayed inceptions for Marine Isotope Stages 18d and 13c, which have also been noted by Parrenin et al. through a comparison of LR04 benthic δ18O and EDC ice core datasets. Finally, the model enables the classification of interglacial periods into two distinct types that approximately account for their durations. This classification also enables a low-resolution estimation of the Holocene termination based solely on celestial mechanical forcing.

Nuclear power has much to offer in addressing the nation’s energy security needs in an environmentally acceptable manner. But today’s fission technology cannot accomplish this without adding to the...

A gravity gradiometer is an incredibly sensitive device whose unit of measure is an eotvos (10‐9 s‐2), which is approximately equal to the gradient of the gravitational field produced by 10 grains (about 7.5 milligrams) of sand at a distance of 1 centimeter. We consider the gradiometer engineered by Draper Laboratories.1 Such a device could be used in portal‐perimeter monitoring to detect gravitational effects produced by the mass distributions of shrouded containers or the contents of railcars and trucks moving through the portals or in observations of missiles to determine the number of warheads they carry or whether extraordinary shielding had been emplaced to block telltale emissions of nuclear radiation. It could also be used in some circumstances to distinguish non‐nuclear cruise missiles from cruise missiles carrying nuclear weapons if measurements that used neutron or gamma‐ray irradiation were considered too intrusive.