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Throughout the 20thcentury, women were leading intellectuals on International Relations (IR). They thought, wrote, and taught on this subject in numerous political, professional, intimate, and intellectual contexts. They wrote some of the earliest and most powerful theoretical statements of what would later become core approaches to contemporary international theory. Yet, historical women, those working before the late 20thcentury, are almost completely missing in IR's intellectual and disciplinary histories, including histories of its main theoretical traditions. In this forum, leading historians and theorists of IR respond to the recent findings of the Leverhulme project on Women and the History of International Thought (WHIT), particularly its first two book-length publications on the centrality of women to early IR discourses and subsequent erasure from its history and conceptualization. The forum is introduced by members of the WHIT project. Collectively, the essays suggest the implications of the erasure and recovery of women's international thought are significant and wide-ranging.

Our ability to specify and forecast ionospheric dynamics and weather at low- and mid-latitudes is strongly limited by our current understanding of the coupling processes in the ionosphere-thermosphere system and the coupling between the high and low latitude regions. Furthermore only a limited number of observations are available for a specification of ionospheric dynamics and weather at these latitudes. As shown by meteorologists and oceanographers, the best specification and weather models are physics-based data assimilation models that combine the observational data with our understanding of the physics of the environment. Through simulation experiments these models can also be used to study the sensitivity of the specification accuracy on different arrangements of observation platforms and observation geometries and can provide important information for the planning of future missions. For example, these studies can provide information about the number of spacecraft needed to improve the specification or evaluate the impact of different observation geometries on the accuracy of the specification. Here we have used the Global Assimilation of Ionospheric Measurements Full-Physics model (GAIM-FP) to study the sensitivity of ionospheric specifications on in situ plasma density observations obtained from electrostatic analyzers (ESA) onboard of a constellation of small satellites. The model is based on an Ensemble Kalman filter technique and a physics-based model of the ionosphere/plasmasphere (IPM), which covers the altitude range from 90 to 20,000 km. The data assimilation model can, in addition to the ESA observations, assimilate bottom-side Ne profiles from ionosondes, slant TEC from ground-based GPS stations, in situ Ne from DMSP satellites, occultation data from several satellites, and line-of-sight UV emissions measured by satellites. Simulation studies have been performed using various ESA constellation arrangements and their impact on the ionospheric specification has been evaluated. The results from this study will be presented with an emphasis on the number of satellites and their orbital geometries needed to improve ionospheric specifications and forecasts.

This paper describes the FalconSAT-2 mission objectives to take advantage of targets of opportunity to make multipoint in situ measurements of ionospheric plasma depletions simultaneously with other spacecraft. Because these plasma depletions are known to interfere with radio transmissions over a broad range of frequencies, including 100-1000 MHz, the international space weather community is investigating the instigation, temporal evolution, and spatial propagation of these structures in the hopes that a prediction tool may be developed to warn operators of outages in communications or navigation. FalconSAT-2 will be launched into a low altitude (360 km), medium inclination (52 degrees) orbit with sensors designed to measure in situ suprathermal plasma spectra at a rate of 10 samples per second. The primary mission objectives are to 1) investigate F region ionospheric plasma depletion morphology relative to geomagnetic activity, and 2) demonstrate the utility of the Miniature Electrostatic Analyzer (MESA) in measuring energy-resolved spectra of ionospheric electrons over a dynamic range such that plasma density depletions down to 0.1% of the background may be resolved at a rate of 10 Hz. Simultaneous in situ multipoint observations of ionospheric plasma depletions are designated as a secondary objective since FalconSAT-2 consists of a single spacecraft, and opportunities to make these simultaneous measurements with other spacecraft in compatible orbits are not in our control. Both deep and shallow bubbles, frequently observed in the pre- and post-midnight sectors, respectively [Singh at al., 1997], are known to exhibit magnetic field-aligned behavior [Fagundes et al., 1997]; thus, there is the expectation (to first order) that multiple spacecraft entering a magnetic flux tube simultaneously have the opportunity to observe a depletion structure at different points within the structure. This observation would provide insight into the plasma depletion extent along the field line. Other conjunction types, such as non-simultaneous intersection of a flux tube or crossing of orbital paths simultaneously in different magnetic flux tubes, provide insight into other aspects of depletion structure, such as constraining the plasma depletion extent and propagation speed along the magnetic field line, or plasma depletion vertical extent. With this paper, a statistical analysis of the probability that FalconSAT-2 will intersect a magnetic flux tube during eclipse simultaneously with other spacecraft capable of measuring thermal electrons is presented.