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The Magnetospheric Auroral Asymmetry Explorer (MAAX) mission makes a major leap forward in determining how magnetosphereionosphere electrodynamic coupling regulates multi-scale auroral energy flow through the near-Earth space environment. Recently proposed to NASA’s Heliophysics Small Explorer program, MAAX accomplishes this by: (1) Understanding how seasons and tilt of the magnetic field regulate energy flow from the solar wind through the system; (2) discovering how the formation, evolution, and interhemispheric asymmetries of nightside meso-scale auroral features are regulated by the auroral background conductance; (3) determining how the time-dependent magnetospheric energy flow controls multi-scale auroral dynamics. The solar wind energy enters the magnetosphere mainly through dayside reconnection and is stored in the magnetosphere, which later converts to plasma and neutral thermal and kinetic energies. Dynamic smaller-scale processes in the nightside magnetosphere map from the magnetosphere to the ionosphere, resulting in auroral structures that have fascinated people for millennia. Observations of the aurora have been used as a window to probe and understand these dynamics even beyond the Earth system. The magnetic field lines in which the aurora occurs thread through both hemispheres. Traditionally, auroral observations from one hemisphere are assumed to be conjugate, while recent observations suggest this may not always be applicable. With auroral observations from one hemisphere, we can only understand some of the processes that control the flow of energy through the system. However, with observations in both with observations in both hemispheres we gain a deeper understanding into the dynamics of this integrated system. MAAX comprises two observatories in circular polar orbits at 20,850 km altitude for viewing of the auroral ovals in both hemispheres. Each observatory carries a single high-heritage UV imager to close the science objectives that operate poleward of +/-35° latitude. For the first year of the mission, the observatories are spaced at 90° to allow continuous coverage on one oval, then the other with a 6-hour duty cycle. This phase also allows for intervals in which both view the same hemisphere or both view the same longitude but different hemispheres. For the second year of the mission, the observatories are spaced at 180° to have simultaneous complete viewing of both the northern and southern auroral ovals with a 4.5 hr/1.5 hr on/off duty cycle. Discussed here is the science motivation of the mission concept and the numerical modeling trade studies to optimize the mission characteristics to achieve the proposed objectives.

The Lunar Environment Heliospheric X-ray Imager (LEXI, lunar flatform) and Solar wind-Magnetosphere-Ionosphere Link Explorer (SMILE, high apogee Earth-orbiter) will take photos of the Earth’s dayside magnetopause and cusps in soft X-rays after their respective launch in 2024 and 2025 for understanding global magnetic reconnection modes under varying solar wind conditions. To support successful science closure, it is critical to develop techniques to extract magnetopause position from observed soft X-ray images. In this presentation, we introduce a new method that derives subsolar magnetopause position (SMP) as a function of a satellite location and a look direction that gives peak soft X-ray emission. Two assumptions are used in this method: 1. The look direction of maximum soft X-ray emission is the tangent to magnetopause, 2. the magnetopause near a subsolar point is nearly spherical and thus the SMP is equal to the radius of magnetopause curvature. We test this magnetopause tracing method by using the anticipated LEXI soft X-ray images under various solar wind conditions. First, we simulate synthetic soft X-ray images observed from various LEXI locations using the OpenGGCM global magnetosphere MHD model. Galactic background, particle background, and Poisson noises are considered in these images. Then, we apply a lowpass filter to the synthetic LEXI images for removing noises and obtaining accurate look angles of soft X-ray peaks. From filtered images, we calculate SMPs for various LEXI locations and solar wind fluxes, and estimate its accuracy by using the SMPs of OpenGGCM as ground truth. Our method estimates SMPs with an accuracy of

Terrestrial ecliptic dayside observations of the exospheric Lyman-α column intensity between 3–15 Earth radii (Re) by UVIS/HDAC at CASSINI have been analysed to derive the neutral exospheric H-density profile at the Earth's ecliptic dayside in this radial range. The data were measured during CASSINIS's swing by manoeuvre at the Earth on 18 August 1999 and are published by (Werner et al., 2004). In this study the dayside HDAC Lyman-α observations published by (Werner et al., 2004) are compared to calculated Lyman-α intensities based on the 3D H-density model derived from TWINS Lyman-α observations between 2008–2010 (Zoennchen et al., 2015). It was found, that both Lyman-α profiles show a very similar radial dependence in particular between 3–8 Re. Between 3.0–5.5 Re impact distance Lyman-α observations of both TWINS and UVIS/HDAC are existing at the ecliptic dayside. In this overlapping region the cross-calibration of the HDAC profile against the calculated TWINS profile was done, assuming, that the exosphere there was similar for both due to comparable space weather conditions. As result of the cross-calibration the conversion factor between counts/s and Rayleigh fc = 3.285 [counts/s/R] is determined for these HDAC observations. Using this factor the radial H-density profile for the Earths ecliptic dayside was derived from the UVIS/HDAC observations, which constrained the neutral H-density there at 10 Re to a value of 35 cm−3. Furthermore, a faster radial H-density decrease was found at distances above 8 Re (≈ r−3) compared to the lower distances 3–7 Re (≈ r−2.37). This increased loss of neutral H above 8 Re might indicate a higher rate of H ionization in the vicinity of the magnetopause at 9–11 Re (near sub solar point) and beyond, because of increasing charge exchange interactions of exospheric H atoms with solar wind ions outside the magnetosphere.

A key link in the Sun – Earth connection is the solar wind coupling with the terrestrial magnetosphere. Mass and energy enter geospace via dayside magnetic reconnection; reconnection in the tail leads to release of energy and particle injection deep into the magnetosphere, causing geomagnetic substorms. The end product of these processes is the visual manifestation of variable auroral emissions. These have been observed both from the ground and from space, the latter for relatively short continuous periods of time. In situ measurements by a fleet of solar wind and magnetospheric missions, current and planned, can provide the most detailed observations of the plasma conditions both in the incoming solar wind and magnetospheric plasma. However, we are still unable to quantify the global effects of the drivers of Sun - Earth connections, and to monitor their evolution with time. This information is the key missing link for developing a comprehensive understanding of how the Sun gives rise to and controls the Earth's plasma environment and space weather. We are now able to take a novel approach to global monitoring of geospace: X-ray imaging of the magnetosheath and cusps is made possible by the X-ray emission produced in the process of solar wind charge exchange, first observed at comets, and subsequently found to occur in the vicinity of solar system planets, including the Earth's magnetosphere. This is where SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) comes in.SMILE is a novel self-standing mission dedicated to observing the solar wind – magnetosphere coupling at Earth via simultaneous X-ray imaging of the magnetosheath and polar cusps (large spatial scales at the magnetopause), UV imaging of global auroral distributions (mesoscale structures in the ionosphere) and in situ solar wind/magnetosheath plasma and magnetic field measurements. SMILE will provide scientific data on solar wind – magnetosphere interaction at the global level while monitoring it continuously for long, uninterrupted periods of time from a highly elliptical northern polar orbit.SMILE is a collaborative mission between ESA and the Chinese Academy of Sciences that was selected in Nov. 2015, adopted into ESA’s Cosmic Vision Programme in March 2019, and is due for launch at the end of 2024. The novel science that SMILE will deliver, the ongoing technical developments and scientific preparations, and the current status of the mission, will be presented.

The LEXI and SMILE missions will provide soft X‐ray images of the Earth's magnetosheath and cusps after their anticipated launch in 2023 and 2024, respectively. The IBEX mission showed the potential of an Energetic Neutral Atom (ENA) instrument to image dayside magnetosheath and cusps, albeit over the long hours required to raster an image with a single pixel imager. Thus, it is timely to discuss the two imaging techniques and relevant science topics. We simulate soft X‐ray and low‐ENA images that might be observed by a virtual spacecraft during two interesting solar wind scenarios: a southward turning of the interplanetary magnetic field and a sudden enhancement of the solar wind dynamic pressure. We employ the OpenGGCM global magnetohydrodynamics model and a simple exospheric neutral density model for these calculations. Both the magnetosheath and the cusps generate strong soft X‐rays and ENA signals that can be used to extract the locations and motions of the bow shock and magnetopause. Magnetopause erosion corresponds closely to the enhancement of dayside reconnection rate obtained from the OpenGGCM model, indicating that images can be used to understand global‐scale magnetopause reconnection. When dayside imagers are installed with high‐ENA inner‐magnetosphere and FUV/UV aurora imagers, we can trace the solar wind energy flow from the bow shock to the magnetosphere and then to the ionosphere in a self‐standing manner without relying upon other observatories. Soft X‐ray and/or ENA imagers can also unveil the dayside exosphere density structure and its response to space weather., Key Points Soft X‐ray and Energetic Neutral Atom (ENA) imaging instruments provide an innovative way to visualize the global solar wind‐magnetosphere interactionHigh‐cadence, wide field‐of‐view soft X‐ray, and ENA images can capture the motion of the bow shock and magnetopauseThe magnetopause motion can reveal the magnetopause reconnection mode on a global scale

Funding Information: QGZ acknowledges Major Project of Chinese National Programs for Fundamental Research and Development 2021YFA0718600 and China Space Agency Project D020301. HZ acknowledges NSF AGS-1352669 and NASA grant 80NSSC18K1376. BL thanks the Centre National d’Etudes Spatiales (CNES; grant nos. APR-W-EEXP/10- 01-01-05 and APR-Z-ETP-E-0010/01-01-05) and GENCI Agency (DARI project; grant no. A0050400295) for their support. TZL is supported by the NASA Living With a Star Jack Eddy Postdoctoral Fellowship Program, administered by the Cooperative Programs for the Advancement of Earth System Science (CPAESS) and is partially supported by NSF award AGS-1941012. HKC acknowledges NSF grants, OIA-1920965 and AGS-1928883 and the NASA grants, 80NSSC18K1043, 80NSSC18K1052 and 80NSSC19K0844. Work at GSFC was supported by NASA’s THEMIS, MMS, and SR programs. The work of DH is supported by National Natural Science Foundation of China (42030101). The research of AK and GF has been supported by the Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network. KO is supported by the Research Council of Norway grant 223252. The authors acknowledge the International Space Science Institute-Beijing for supporting the international team “Dayside Transient Phenomena and Their Impact on the Magnetosphere-Ionosphere”. Funding Information: QGZ acknowledges Major Project of Chinese National Programs for Fundamental Research and Development 2021YFA0718600 and China Space Agency Project D020301. HZ acknowledges NSF AGS-1352669 and NASA grant 80NSSC18K1376. BL thanks the Centre National d’Etudes Spatiales (CNES; grant nos. APR-W-EEXP/10- 01-01-05 and APR-Z-ETP-E-0010/01-01-05) and GENCI Agency (DARI project; grant no. A0050400295) for their support. TZL is supported by the NASA Living With a Star Jack Eddy Postdoctoral Fellowship Program, administered by the Cooperative Programs for the Advancement of Earth System Science (CPAESS) and is partially supported by NSF award AGS-1941012. HKC acknowledges NSF grants, OIA-1920965 and AGS-1928883 and the NASA grants, 80NSSC18K1043, 80NSSC18K1052 and 80NSSC19K0844. Work at GSFC was supported by NASA’s THEMIS, MMS, and SR programs. The work of DH is supported by National Natural Science Foundation of China (42030101). The research of AK and GF has been supported by the Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network. KO is supported by the Research Council of Norway grant 223252. The authors acknowledge the International Space Science Institute-Beijing for supporting the international team “Dayside Transient Phenomena and Their Impact on the Magnetosphere-Ionosphere”. Publisher Copyright: © 2022, The Author(s). Dayside transients, such as hot flow anomalies, foreshock bubbles, magnetosheath jets, flux transfer events, and surface waves, are frequently observed upstream from the bow shock, in the magnetosheath, and at the magnetopause. They play a significant role in the solar wind-magnetosphere-ionosphere coupling. Foreshock transient phenomena, associated with variations in the solar wind dynamic pressure, deform the magnetopause, and in turn generates field-aligned currents (FACs) connected to the auroral ionosphere. Solar wind dynamic pressure variations and transient phenomena at the dayside magnetopause drive magnetospheric ultra low frequency (ULF) waves, which can play an important role in the dynamics of Earth’s radiation belts. These transient phenomena and their geoeffects have been investigated using coordinated in-situ spacecraft observations, spacecraft-borne imagers, ground-based observations, and numerical simulations. Cluster, THEMIS, Geotail, and MMS multi-mission observations allow us to track the motion and time evolution of transient phenomena at different spatial and temporal scales in detail, whereas ground-based experiments can observe the ionospheric projections of transient magnetopause phenomena such as waves on the magnetopause driven by hot flow anomalies or flux transfer events produced by bursty reconnection across their full longitudinal and latitudinal extent. Magnetohydrodynamics (MHD), hybrid, and particle-in-cell (PIC) simulations are powerful tools to simulate the dayside transient phenomena. This paper provides a comprehensive review of the present understanding of dayside transient phenomena at Earth and other planets, their geoeffects, and outstanding questions.

Geomagnetically induced currents (GIC) can drive power outages and damage power grid components while also affecting pipelines and train systems. Developing the ability to predict local GICs is important to protecting infrastructure and limiting the impact of geomagnetic storms on public safety and the economy. While GIC data is not readily available, variations in the magnetic field, dB/dt, measured by ground magnetometers can be used as a proxy for GICs. We are developing a set of neural networks to predict the east and north components of the magnetic field, BE and BN, from which the horizontal component, BH, and its variation in time, dBH/dt, are calculated. We apply two techniques for time series analysis to study the connection of solar wind and interplanetary magnetic field properties obtained from the OMNI dataset to the ground magnetic field perturbations. The analysis techniques include a feed-forward artificial neural network (ANN) and a long-short term memory (LSTM) neural network. Here we present a comparison of both models' performance when predicting the BH component of the Ottawa (OTT) ground magnetometer for the year 2011 and 2015 and then when attempting to reconstruct the time series of BH for two geomagnetic storms that occurred on 5 August 2011 and 17 March 2015.

Challenges to studying the ionosphere’s ability to conduct electrical currents undercut scientists’ efforts to improve space weather forecasting models. Let’s tackle them together.

The coupling between the solar wind and the Earth's magnetosphere-ionosphere system, and the geospace dynamics that result, comprise some of the key questions in space plasma physics. In situ measurements by a fleet of solar wind and magnetospheric missions, current and planned, can provide the most detailed observations of the Sun-Earth connections. However, we are still unable to quantify the global effects of the drivers of such connections, and to monitor their evolution with time. This information is the key missing link for developing a comprehensive understanding of how the Sun gives rise to and controls the Earth's plasma environment and space weather.SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) is a novel self-standing mission dedicated to observing the solar wind - magnetosphere coupling via simultaneous X-ray imaging of the magnetosheath and polar cusps (large spatial scales at the magnetopause), UV imaging of global auroral distributions (mesoscale structures in the ionosphere) and in situ solar wind/magnetosheath plasma and magnetic field measurements. X-ray imaging of the magnetosheath and cusps is made possible by the X-ray emission produced in the process of solar wind charge exchange, first observed at comets, and subsequently found to occur in the vicinity of the Earth's magnetosphere. One of the science aims of SMILE is to track the substorm cycle, via X-ray imaging on the dayside and by following its consequences on the nightside with UV imaging. SMILE is a collaborative mission between ESA and the Chinese Academy of Sciences (CAS) that was selected in November 2015, adopted into ESA’s Cosmic Vision Programme in March 2019, and is due for launch at the end of 2023. The science that SMILE will deliver, as well as the ongoing technical developments and scientific preparations, and the current status of the mission, will be presented.

It is a relatively recent discovery that charge exchange soft X-ray emission is produced in the interaction of solar wind high charge ions with neutrals in the Earth’s exosphere; this has led to the realization that imaging this emission will provide us with a global and novel way to study solar-terrestrial interactions.In particular X-ray imaging will provide us with the means of establishing the location of the magnetopause and the morphology of the magnetospheric cusps. Variations of the magnetopause standoff distance indicate global magnetospheric compressions and expansions, both in response to solar wind variations and internal magnetospheric processes.Soft X-ray imaging is one of the main objectives of SMILE (Solar wind Magnetosphere Ionosphere Link Explorer), a joint space mission by ESA and the Chinese Academy of Sciences, which is under development and is due for launch in 2023. This presentation will introduce the scientific aims of SMILE, show simulations of the expected images to be returned by SMILE’s Soft X-ray Imager for different solar wind conditions, and will discuss some of the techniques that will be applied in order to extract the positions of the Earth’s magnetic boundaries, such as the magnetopause standoff distance.

We report the concurrent observations of F-region plasma changes and field-aligned currents (FACs) above isolated proton auroras (IPAs) associated with electromagnetic ion cyclotron Pc1 waves. Key events on March 19, 2020 and September 12, 2018 show that ground magnetometers and all-sky imagers detected concurrent Pc1 wave and IPA, during which NOAA POES observed precipitating energetic protons. In the ionospheric F-layer above the IPA zone, the Swarm satellites observed transverse Pc1 waves, which span wider latitudes than IPA. Around IPA, Swarm also detected the bipolar FAC and localized plasma density enhancement, which is occasionally surrounded by wide/shallow depletion. This indicates that wave-induced proton precipitation contributes to the energy transfer from the magnetosphere to the ionosphere.

Entire fields of science, most notably in astrophysics, rely on line-of-sight observations. In planetary science and heliophysics, the techniques of soft X-ray and energetic neutral atom (ENA) imaging also produce line-of-sight measurements. An important question is whether the geometry of the surface, for example the magnetopause, can be reconstructed using only line-of-sight observations from a single spacecraft. Under a broad range of conditions, the peak emission corresponds to the tangent to the boundary surface, such as the planetary surface or magnetopause, the so-called "limb brightening" phenomenon. Thus, line-of-sight observations frequently provide information concerning the tangent to the surfaces being observed. We present an algorithm to reconstruct the cross-section of the magnetopause using line-of-sight soft X-ray observations (and, in principle, ENA observations). The algorithm successfully reconstructs the cross section of the magnetopause in the orbit plane. The threedimensional magnetopause structure can be recovered from observations by a spacecraft whose orbit precesses around the magnetosphere.

The BATSRUS model was run at the Community Coordinate Modeling Center (CCMC). The results can be found through run Brian_Walsh_030413_1.

We examine the response of the thermosphere to the impact of solar wind dynamic pressure enhancements using observations and global magneto-hydrodynamics (MHD) simulations by the OpenGGCM model. Combining neutral density observations from the Challenging Minisatellite Payload (CHAMP) and the Gravity Recovery and Climate Experiment (GRACE) satellites with simultaneous Poynting flux measurements from the Defense Meteorological Satellite Program (DMSP) F16, we find that thermospheric density as well as downward Poynting flux intensified shortly after a sudden enhancement of the solar wind dynamic pressure. The intensification manifested mostly on the dayside high-latitude region with peak intensity in the vicinity of the noon and prenoon cusp. OpenGGCM modeling results show that the ionospheric Joule heating increased abruptly in response to the sudden enhancement of the dynamic pressure in the same region as the observed Poynting flux and neutral density enhancements. The modeling results show that the enhanced Joule heating coincides, both in time and location, with the appearance of a pair of high-latitude localized field-aligned currents (FACs) in the cusp region. The FACs intensified and extended azimuthally. Coincidental with the solar wind dynamic pressure enhancement, the y component of the interplanetary magnetic field (IMF) By became strongly positive and, in addition, had some large fluctuations. We explore the separate and combined effects of the dynamic pressure and IMF By perturbations, with specifically designed simulation experiments that isolate the effect of each solar wind parameter. We find that the dynamic pressure enhancement is the primary source for the Joule heating and neutral density enhancements, but the IMF By modulates the level of enhancement.

When, where, and which type of reconnection (antiparallel or component) happens on the dayside magnetopause are long-standing unsolved questions due to insufficient in situ observation of reconnection sites. Previous studies showed that the dispersed ion signatures observed in the magnetospheric cusps depend on the reconnection mechanism, suggesting that cusp ion signatures can be a good tool to investigate the locations and properties of dayside reconnection. We investigate this close relation between cusp signatures and magnetopause reconnection for four different interplanetary magnetic field (IMF) clock angles (CA) using the Open Global Geospace Circulation Model (OpenGGCM) and the Liouville Theorem Particle Tracer(LTPT). OpenGGCM produces dayside reconnection under the resistive MHD theory, and LTPT calculates cusp ion signatures caused by the simulated reconnection. Our model results show that for CA = 0∘, antiparallel reconnection at both the northern and southern lobes causes a reverse dispersion in which ion energies increase with increasing latitude. For CA = 60∘, unsteady antiparallel reconnection at both the northern and southern lobes causes double reverse dispersions. For CA = 120∘, component reconnection near the subsolar point produces a dispersionless signature in the low-latitude cusp, and antiparallel reconnection on the duskside northern magnetopause produces a normal dispersion in the high-latitude cusp in which ion energies decrease with increasing latitude. For CA = 180∘, antiparallel reconnection near the subsolar point causes a normal dispersion.

This study investigates how solar wind energy is deposited into the magnetosphere-ionosphere system during sudden enhancements of solar wind dynamic pressure (Psw), using the coupled Open Geospace General Circulation Model–Coupled Ionosphere Thermosphere Model (OpenGGCM-CTIM) 3-D global magnetosphere-ionosphere-thermosphere model. We simulate three unique events of solar wind pressure enhancements that occurred during negative, near-zero, and positive interplanetary magnetic field (IMF) Bz. Then, we examine the behavior of the dayside and nightside reconnection rates and quantify their respective contributions to cross polar cap potential (CPCP), a proxy of ionospheric plasma convection strength. The modeled CPCP increases after a Psw enhancement in all three cases, which agrees well with observations from the Defense Meteorological Satellite Program spacecraft and predictions from the assimilative mapping of ionospheric electrodynamics technique. In the OpenGGCM-CTIM model, dayside reconnection increases within 9–13 min of the pressure impact, while nightside reconnection intensifies about 13–25 min after the pressure increase. As the strong Psw compresses the dayside magnetosheath and, subsequently, the magnetotail, their magnetic fields intensify and activate stronger antiparallel reconnection on the dayside magnetopause first and near the central plasma sheet second. For southward IMF, dayside reconnection contributes to the CPCP enhancement 2–4 times more than nightside reconnection. For northward IMF, the dayside contribution weakens, and nightside reconnection contributes more to the CPCP enhancement. We find that high-latitude magnetopause reconnection during northward IMF produces sunward ionospheric plasma convection, which decreases the typical dawn-to-dusk ionosphere electric field. This results in a weaker dayside reconnection contribution to the CPCP during northward IMF.

The magnetosphere is a major source of energy for the Earth's ionosphere and thermosphere (IT) system. Current IT models drive the upper atmosphere using empirically calculated magnetospheric energy input. Thus, they do not sufficiently capture the storm-time dynamics, particularly at high latitudes. To improve the prediction capability of IT models, a physics-based magnetospheric input is necessary. Here, we use the Open Global General Circulation Model (OpenGGCM) coupled with the Coupled Thermosphere Ionosphere Model (CTIM). OpenGGCM calculates a three-dimensional global magnetosphere and a two-dimensional high-latitude ionosphere by solving resistive magnetohydrodynamic (MHD) equations with solar wind input. CTIM calculates a global thermosphere and a high-latitude ionosphere in three dimensions using realistic magnetospheric inputs from the OpenGGCM. We investigate whether the coupled model improves the storm-time IT responses by simulating a geomagnetic storm that is preceded by a strong solar wind pressure front on August 24, 2005. We compare the OpenGGCM-CTIM results with low-earth-orbit satellite observations and with the model results of Coupled Thermosphere-Ionosphere-Plasmasphere electrodynamics (CTIPe). CTIPe is an up-to-date version of CTIM that incorporates more IT dynamics such as a low-latitude ionosphere and a plasmasphere, but uses empirical magnetospheric input. OpenGGCMCTIM reproduces localized neutral density peaks at approx. 400 km altitude in the high-latitude dayside regions in agreement with in situ observations during the pressure shock and the early phase of the storm. Although CTIPe is in some sense a much superior model than CTIM, it misses these localized enhancements. Unlike the CTIPe empirical input models, OpenGGCM-CTIM more faithfully produces localized increases of both auroral precipitation and ionospheric electric fields near the high-latitude dayside region after the pressure shock and after the storm onset, which in turn effectively heats the thermosphere and causes the neutral density increase at 400 km altitude.

The production factor, or broad band averaged cross-section, for solar wind charge-exchange with hydrogen producing emission in the ROSAT 1/4 keV (R12) band is $3.8\pm0.2\times10^{-20}$ count degree$^{-2}$ cm$^4$. This value is derived from a comparison of the Long-Term (background) Enhancements in the ROSAT All-Sky Survey with magnetohysdrodynamic simulations of the magnetosheath. This value is 1.8 to 4.5 times higher than values derived from limited atomic data, suggesting that those values may be missing a large number of faint lines. This production factor is important for deriving the exact amount of 1/4 keV band flux that is due to the Local Hot Bubble, for planning future observations in the 1/4 keV band, and for evaluating proposals for remote sensing of the magnetosheath. The same method cannot be applied to the 3/4 keV band as that band, being composed primarily of the oxygen lines, is far more sensitive to the detailed abundances and ionization balance in the solar wind. We also show, incidentally, that recent efforts to correlate XMM-Newton observing geometry with magnetosheath solar wind charge-exchange emission in the oxygen lines have been, quite literally, misguided. Simulations of the inner heliosphere show that broader efforts to correlate heliospheric solar wind charge-exchange with local solar wind parameters are unlikely to produce useful results., Comment: 19 pages, 16 figures, submitted to ApJ