This work defines an extension CERES of the first-order cut-elimination method CERES to the subclass of sequent calculus proofs in second-order logic using quantifier-free comprehension. This extension is motivated by the fact that cut-elimination can be used as a tool to extract information from real mathematical proofs, and often a crucial part of such proofs is the definition of sets by form...

We consider the full Solar System including (1) Ceres and some of the main asteroids, (2) Pallas, (4) Vesta, (7) Iris, and (324) Bamberga. We show that close encounters among these small bodies induce strong chaotic behavior in their orbits and in those of many asteroids that are much more chaotic than previously thought. Even if space missions will allow very precise measurements of the positi...

Prior to the arrival of the Dawn spacecraft at Ceres, the dwarf planet was anticipated to be ice-rich. Searches for morphological features related to ice have been ongoing during Dawn's mission at Ceres. Here we report the identification of pitted terrains associated with fresh Cerean impact craters. The Cerean pitted terrains exhibit strong morphological similarities to pitted materials previo...

Thermochemical models have predicted that Ceres, is to some extent, differentiated and should have an icy crust with few or no impact craters. We present observations by the Dawn spacecraft that reveal a heavily cratered surface, a heterogeneous crater distribution, and an apparent absence of large craters. The morphology of some impact craters is consistent with ice in the subsurface, which mi...

Introduction: The dwarf planet Ceres is the largest object in the asteroid belt and is a primary target of NASA’s Dawn mission [1]. Recent modeling has shown that Ceres is likely differentiated and consists of a thin silicate+ice crust underlain by a thicker water ice mantle [2,3]. The presence of hydrated phases on Ceres, as inferred from the 3 μm absorption feature present in surface reflecta...

The combination of remote sensing and crop growth models has become an effective tool for yield estimation and a potential method for grain quality estimation. In this study, two assimilation variables (derived from a hyperspectral sensor), called leaf area index (LAI) and canopy nitrogen accumulation (CNA), were jointly used to calibrate the sensitive parameters and initial states of the DSSAT...

In support for the ISO Mission it has been necessary to establish a set of asteroids as photometric standards for the photometric calibration of the instruments (M uller & Lagerros 1998). The new standards are described as rotating ellipsoids. Illumination geometry, heat transfer due to non-zero thermal inertia and surface structure/porosity are taken into account. The characteristic properties...