Random bombardment by comets, asteroids and associated fragments form and alter the lunar regolith and other rocky surfaces. The accumulation of impact craters over time is of fundamental use in evaluating the relative ages of geologic units. Crater counts and radiometric ages from returned samples provide constraints with which to derive absolute model ages for unsampled units on the Moon and other Solar System objects. However, although studies of existing craters and returned samples offer insight into the process of crater formation and the past cratering rate, questions still remain about the present rate of crater production, the effect of early-stage jetting during impacts and the influence that distal ejecta have on the regolith. Here we use Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) temporal ('before and after') image pairs to quantify the contemporary rate of crater production on the Moon, to reveal previously unknown details of impact-induced jetting, and to identify a secondary impact process that is rapidly churning the regolith. From this temporal dataset, we detected 222 new impact craters and found 33 per cent more craters (with diameters of at least ten metres) than predicted by the standard Neukum production and chronology functions for the Moon. We identified broad reflectance zones associated with the new craters that we interpret as evidence of a surface-bound jetting process. We also observe a secondary cratering process that we estimate churns the top two centimetres of regolith on a timescale of 81,000 years-more than a hundred times faster than previous models estimated from meteoritic impacts (ten million years).

The model-driven software development paradigm requires that appropriate model transformations are applicable in different stages of the development process. The transformations have to consistently propagate changes between the different involved models and thus ensure a proper model synchronization. However, most approaches today do not fully support the requirements for model synchronization and focus only on classical one-way batch-oriented transformations. In this paper, we present our approach for an incremental model transformation which supports model synchronization. Our approach employs the visual, formal, and bidirectional transformation technique of triple graph grammars. Using this declarative specification formalism, we focus on the efficient execution of the transformation rules and how to achieve an incremental model transformation for synchronization purposes. We present an evaluation of our approach and demonstrate that due to the speedup for Communicated by Prof. Oscar Nierstrasz. This work was partly developed in the course of the Collaborative Research Center 614-Self-optimizing Concepts and Structures in Mechanical Engineering-University of Paderborn, and was published on its behalf and funded by the Deutsche Forschungsgemeinschaft. This article is an extended version of [17].the incremental processing in the average case even larger models can be tackled.

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Lunar Reconnaissance Orbiter Camera images reveal the presence of steep-walled pits in mare basalt (n=8), impact melt deposits (n=221), and highland terrain (n=2). Pits represent evidence of subsurface voids of unknown extents. By analogy with terrestrial counterparts, the voids associated with mare pits may extend for hundreds of meters to kilometers in length, thereby providing extensive potential habitats and access to subsurface geology. Because of their small sizes relative to the local equilibrium crater diameters, the mare pits are likely to be post-flow features rather than volcanic skylights. The impact melt pits are indirect evidence both of extensive subsurface movement of impact melt and of exploitable sublunarean voids. Due to the small sizes of pits (mare, highland, and impact melt) and the absolute ages of their host materials, it is likely that most pits formed as secondary features.

The lateral accessory lobes (LALs) are prominent integration centers in the insect brain. In the desert locust Schistocerca gregaria, they are connected with the anterior optic tubercles (AOTus), with the central complex, and with the ventral nerve cord. Two subcompartments of the LALs, the lateral triangle and the median olive, are easily recognized by their prominent granular texture. Both areas are part of the polarization vision pathway in the locust brain; they receive input from projection neurons of the AOTu and are the site of presumed dendritic arborizations of tangential neurons of the lower division of the central body. Both types of neuron are sensitive to polarized light and most likely play a role in sky compass navigation of the locust. We show here that neurons from the AOTu and tangential neurons of the central body form large microglomerular contacts in the median olive and lateral triangle. Presynaptic elements from the AOTu end in small numbers of large cup-shaped terminals. These cups enclose many small gamma-aminobutyric acid (GABA)-immunoreactive (-ir) profiles from tangential neurons of the lower division of the central body. Each cup-shaped profile makes numerous (>150) dyadic output synapses with the small postsynaptic GABA-ir profiles. No synaptic connections were found between the small core profiles. The microglomerular organization of the median olive and lateral triangle is unlike that of any other synaptic microglomeruli reported for the insect brain. It might provide precise spike timing information possibly used to extract spatial information by comparison of binocular inputs in the central complex.