The Fast Plasma Investigation (FPI) was developed for flight on the Magnetospheric Multiscale (MMS) mission to measure the differential directional flux of magnetospheric electrons and ions with unprecedented time resolution to resolve kinetic-scale plasma dynamics. This increased resolution has been accomplished by placing four dual 180-degree top hat spectrometers for electrons and four dual 180-degree top hat spectrometers for ions around the periphery of each of four MMS spacecraft. Using electrostatic fieldof-view deflection, the eight spectrometers for each species together provide 4pi-sr field-ofview with, at worst, 11.25-degree sample spacing. Energy/charge sampling is provided by swept electrostatic energy/charge selection over the range from 10 eV/q to 30000 eV/q. The eight dual spectrometers on each spacecraft are controlled and interrogated by a single block redundant Instrument Data Processing Unit, which in turn interfaces to the observatory's Instrument Suite Central Instrument Data Processor. This paper describes the design of FPI, its ground and in-flight calibration, its operational concept, and its data products.

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The history of the genus Pan is a topic of enduring interest. Chimpanzees (Pan troglodytes) are often divided into subspecies, but the population structure and genetic history of chimpanzees across Africa remain unclear. Some population genetics studies have led to speculation that, until recently, this species constituted a single population with ongoing gene flow across its range, which resulted in a continuous gradient of allele frequencies. Chimpanzees, designated here as P. t. ellioti, occupy the Gulf of Guinea region that spans southern Nigeria and western Cameroon at the center of the distribution of this species. Remarkably, few studies have included individuals from this region, hindering the examination of chimpanzee population structure across Africa. Here, we analyzed microsatellite genotypes of 94 chimpanzees, including 32 designated as P. t. ellioti. We find that chimpanzees fall into three major populations: (i) Upper Guinea in western Africa (P. t. verus); (ii) the Gulf of Guinea region (P. t. ellioti); and (iii) equatorial Africa (P. t. troglodytes and P. t. schweinfurthii). Importantly, the Gulf of Guinea population is significantly different genetically from the others, sharing a last common ancestor with the populations in Upper Guinea ∼0.46 million years ago (mya) and equatorial Africa ∼0.32 mya. Equatorial chimpanzees are subdivided into up to three populations occupying southern Cameroon, central Africa, and eastern Africa, which may have constituted a single population until ∼0.10-0.11 mya. Finally, occasional hybridization may be occurring between the Gulf of Guinea and southern Cameroon populations.chimpanzees | phylogenetics | population biology | microsatellites R evealing the histories of chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) is of widespread and enduring interest due to their close relationship with humans. A recent proliferation of research shows that we are just beginning to unravel their complex histories (1), and even now, we still debate the number of species and subspecies belonging to the genus Pan. Most authorities agree that chimpanzees and bonobos should be classified as different species, with their ranges separated by the Congo River ( Fig. 1; ref. 2). Chimpanzees are frequently further divided into subspecies across tropical Africa (2, 3), but this classification is disputed (4). P. t. verus occupies the Upper Guinea region of western Africa (2, 3). The range of P. t. troglodytes extends through central Africa. P. t. schweinfurthii occupies eastern Africa (2, 3) and has been proposed to be split into two subspecies, P. t. schweinfurthii and P. t. marungensis, based on craniometric variation (5).The subspecies name P. t. ellioti (6), formerly P. t. vellerosus (7, 8), has been proposed for chimpanzees from the Gulf of Guinea region, which spans southern Nigeria and western Cameroon (9). However, relatively little is known about the genetic history of chimpanzees from this region, and some question their distinctiveness from adjacent populations (4). Ana...

We describe the development, launch into space, and initial results from a prototype wide field-of-view soft X-ray imager that employs lobster-eye optics and targets heliophysics, planetary, and astrophysics science. The sheath transport observer for the redistribution of mass is the first instrument using this type of optics launched into space and provides proof-of-concept for future flight instruments capable of imaging structures such as the terrestrial cusp, the entire dayside magnetosheath from outside the magnetosphere, comets, the Moon, and the solar wind interaction with planetary bodies like Venus and Mars [Kuntz et al., Astrophys. J. (in press)].

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