Magnetic and gravity derivatives can be likened to seismic attributes in that they can help define/estimate the physical properties of the source structure causing the anomaly. This contribution looks at the tilt derivative, first reported in 1994 and more recently used to derive the local wavenumber (1997). We will show that the combination of the tilt derivative and its total horizontal derivative are highly suitable for mapping shallow basement structure and mineral exploration targets and that they have distinct advantages over many conventional derivatives. We provide the simple theory behind the derivatives, use a range of simple 2D models to illustrate their response, and apply them to mapping a mineral target in Namibia.Tilt derivative (TDR). The physical properties of a magnetic source structure that can be determined from a grid of magnetic data include its shape (plan), location of its edges, depth to top edges, dip, and rock susceptibility contrast. This contribution will focus on the first two-i.e. shape and edge detection. The problems to be overcome in data enhancement are to identify and map (a) subtle anomalies attenuated in the dynamic range due to the presence of high amplitude magnetic anomalies, (b) the continuity of individual bodies where there are lateral changes in susceptibility and/or depth of burial, and (c) the edges of structures by adequately accounting for the nature of the rock magnetization. Rock magnetization is a vector quantity that can consist of both remanent and geomagnetically induced components. The presence of the remanent component can adversely affect the shape of the magnetic field response and result in spurious derivatives, if one has assumed that only the induced component is present. Fortunately, basement rocks are usually dominated by the induced component, whereas mineralized zones often host long-lived remanent components. The following theory and 2D model examples show how these three problems can be successfully overcome, thus generating maps that can provide more reliable descriptions of source body parameters.

During 2014 and 2015, NASA's Neutron star Interior Composition Explorer (NICER) mission proceeded successfully through Phase C, Design and Development. An X-ray (0.2-12 keV) astrophysics payload destined for the International Space Station, NICER is manifested for launch in early 2017 on the Commercial Resupply Services SpaceX-11 flight. Its scientific objectives are to investigate the internal structure, dynamics, and energetics of neutron stars, the densest objects in the universe. During Phase C, flight components including optics, detectors, the optical bench, pointing actuators, electronics, and others were subjected to environmental testing and integrated to form the flight payload. A custom-built facility was used to co-align and integrate the X-ray "concentrator" optics and silicon-drift detectors. Ground calibration provided robust performance measures of the optical (at NASA's Goddard Space Flight Center) and detector (at the Massachusetts Institute of Technology) subsystems, while comprehensive functional tests prior to payload-level environmental testing met all instrument performance requirements. We describe here the implementation of NICER's major subsystems, summarize their performance and calibration, and outline the component-level testing that was successfully applied.

A study was made of 58 male Broadmoor patients who had killed their mothers. In most cases the homicides occurred in association with a schizophrenic illness. The remaining patients were diagnosed as suffering from endogenous depressions or personality disorders. Within a predominantly psychotic framework, the matricides often appeared to be a response to a close confining mother/son relationship. This was characterized by a dominant mother and an immature, dependent son, who had frequently lost his father some years before the homicide.

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