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The Emirates Mars Ultraviolet Spectrometer (EMUS) onboard the Emirates Mars Mission spacecraft, which observes ultraviolet emission between approximately 100 and 170 nm, has observed multiple instances of nightside aurora at Mars. Variations in the auroral brightness and morphology have been observed to change on timescales of tens of minutes. The brightest aurorae are typically seen following space weather events, i.e., coronal mass ejection and stream interaction region impacts. The InSight Fluxgate Magnetometer (IFG) on the Interior Explorations using Seismic Investigations, Geodesy and Heat Transport (InSight) lander measured the magnetic field at the surface of Mars. IFG has measured variations in the nightside surface magnetic field, presumably due to variations in ionospheric and magnetospheric currents. Periodic and aperiodic variations in the surface field have been observed, including with timescales of a few minutes to tens of minutes. The magnitude of the fluctuations is often larger following space weather events. We examine the connection between the presence of aurora as observed by EMUS and surface magnetic field fluctuations as measured by IFG. Coincident EMUS and IFG observations show enhanced surface magnetic field fluctuations during times when aurorae were present. Additionally, the timescale of fluctuations in the auroral brightness are similar to the timescale of surface magnetic field fluctuations for non-coincident observations. These results suggest that IFG measured the surface magnetic field effect of time varying ionospheric auroral currents.

The Emirates Mars Mission (EMM) Hope probe launched on 20 Jul 2020 and entered Mars orbit on 9 Feb 2021, carrying a payload of 3 complementary instruments to characterize the global atmosphere across the full range of altitudes (surface to exosphere) at diurnal and seasonal timescales. The unique, high-altitude orbit of the Hope probe (19,970 km periapse, 42,650 km apoapse altitude, 25 deg inclination, 54.5-hour period) that enables its synoptic view of the red planet also brings the spacecraft across the orbit of Mars’ outermost moon, Deimos. The Hope trajectory was slightly modified by two maneuvers in Aug 2022 and Jan 2023 that will allow the surface of Deimos to be observed in a series of flybys in Feb-Mar 2023. Here we present preliminary results from the Emirates Mars Ultraviolet Spectrometer (EMUS), an imaging spectrograph with a wavelength range of 100-170 nm and a field of view of 10.75 x 0.18 deg (using the high-resolution slit position). We will derive the absolute reflectance of the surface, search for any compositionally distinct spectral features (e.g. carbon, polycyclic aromatic hydrocarbons, water ice), and examine any spatial heterogeneity across the surface.

Atomic hydrogen and oxygen are the dominant species in the Martian exosphere. Atomic hydrogen is essentially produced from the dissociation of H2O, whereas, hot oxygen atoms are populated by non-thermal processes such as the dissociative recombination of O2+ with electrons in the Martian ionosphere. The study of these species helps to understand the evolution of the Martian atmosphere and more specifically the history of water on Mars. The Emirates Mars Ultraviolet Spectrometer (EMUS), one of the primary instruments onboard the Emirates Mars Mission (EMM), has been observing atomic hydrogen and oxygen in the Martian exosphere over the Mars Year 36. We present the analysis of the cross-exospheric observations by the EMUS for hydrogen Lyman series and oxygen 130.4 nm emissions and their seasonal variability. The EMUS cross-exospheric observations cover the tangent altitude starting from 130 km to more than 35,000 km above the disk (see Fig. 1), with most of the observations below 25,000 km. The observations show that when Mars moved from perihelion to aphelion, the hydrogen emission line intensities increase by an order of magnitude or more whereas, for oxygen, it is an increment by a factor of about 2 at larger altitudes. Based on these observations, we also discuss the retrieval of densities, temperature, and the estimation of escape fluxes of hydrogen and oxygen species by applying 3D hydrogen ballistic corona and 3D Monte Carlo particle transport models, respectively.Figure 1: The EMM-observed cross-exosphere emission intensity profiles of atomic hydrogen and oxygen during Mars Year 3

One of the primary objectives of the Emirates Mars Mission (EMM) is to study the seasonal variation of the upper atmosphere of Mars and associated changes in the escape of atmosphere to space. Here we present a preliminary analysis of the oxygen population in the inner exosphere (1.06-1.6 Martian radii) with nearly-contiguous sampling across all Martian seasons from early MY 36 to early MY 37. This oxygen is thought to be a non-thermal photochemically generated population driven by solar EUV, which can produce energetic atoms with sufficient velocity to escape Mars’ gravity. The observations are made by measuring the atomic oxygen emission at 130.4 nm using the Emirates Mars Ultraviolet Spectrometer (EMUS). We compare the brightness of the exospheric oxygen population with the thermospheric population ( < 1.06 Mars radii, or < 200 km) and find that the exosphere is much more responsive to seasonal variations in solar energy input. The seasonal variations cannot be explained by modulations in solar irradiance at 130.4 nm alone, and are consistent with the expectation that the extended oxygen exosphere at Mars is generated by a photochemical source.

The surface of the planet Mars exhibits a record of dessiccation and oxidation, the legacy of significant water escape to space as hydrogen and oxygen. This H escape can be constrained using ultraviolet observations of the planet's upper atmosphere, where neutral atomic hydrogen scatters UV sunlight. In the time since its orbit insertion in early 2021, the Emirates Mars Ultraviolet Spectrometer (EMUS) on the Emirates Mars Mission (EMM) has been observing this hydrogen at 102.6 nm and 121.6 nm, H Lyman beta and Lyman alpha. Here we present H escape rates retrieved from these observations, obtained using a 3D radiative transfer model that simulates the brightness of both spectral lines, combining their information content to constrain the atmospheric state. In agreement with past results, we find that H escape peaks around Southern Summer solstice, after perihelion, exhibiting a more than 10x increase relative to Northern Summer conditions. Importantly, our retrievals extract information about both the hydrogen density and temperature, and do not require independent assumptions about the upper atmosphere temperature. We will discuss prospects for extending these retrievals beyond the current EMM dataset as well as implications for the long-term evolution of the Mars atmosphere.

The major scientific objective of the Emirates Mars Mission (EMM) is to explore the global atmospheric dynamics of the Martian atmosphere both in short term (diurnal) and long term (seasonal). The Emirates Mars Ultraviolet Spectrometer (EMUS) instrument on board the EMM makes two-dimensional images ( in extreme and far ultraviolet wavelengths: 90-170 nm) of the Martian disk and exosphere to characterize the neutral densities in the thermosphere and exosphere of Mars. In this paper, we will present the first results from the stellar occultation measurements made by the EMUS instruments in October 2022. These occultation observations were not part of the original science planning and were added as a bonus EMM science. A total of seven stellar occultations were performed during the two EMM orbits spanning between 24 to 27 October. These measurements were the first stellar occultation of Mars in the EUV wavelengths (90-110 nm). Due to the higher sensitivity of the EMUS instrument, the occultation measurements were able to probe the atmosphere with an altitude sampling of 2 km or lower. The occultation measurements by SPICAM/MEx and IUVS/MAVEN were limited to 160 km due to wavelengths limited to a longward of 110 nm. However, the use of EUV wavelengths in the EMUS stellar occultation provided atmospheric probing up to 190 km thus enabling neutral density retrieval up to the exobase region of Mars. The CO2 densities are retrieved from 90-185 km and the temperature profiles were retrieved using the constraint of hydrostatic equilibrium to the CO2 densities. We shall discuss results from the EMUS occultation campaign specifically the observed variability in the CO2 density and temperature during the occultation campaign.

We present the first continuous observations of the extreme and far ultraviolet (EUV and FUV) dayglow emissions measured by Emirates Mars Ultraviolet Spectrometer (EMUS) onboard the Emirates Mars Mission. We found excellent agreement between the previous observations from the Hopkins Ultraviolet Telescope and recent observations by EMUS both in shape and magnitude. We presented the average disk brightness of major EUV and FUV emissions for about 10 months of data from April 2021 to February 2022. The solar activity was mild/minimum during the first half of the period presented in this study, but we noticed significant day-to-day variations in the major dayglow emissions independent of solar activity, indicating possible coupling from the lower atmosphere via waves/tides. The solar activity increased significantly during the second half of the study period. Our analysis showed that all major EUV and FUV emissions are highly correlated with solar forcing as well as seasonal changes. UAE government; NASA Published version Funding for the development of the Emirates Mars Mission mission was provided by the UAE government, and to co-authors outside of the UAE by MBRSC. Ed Thiemann, Phil Chamberlin, and Frank Eparvier are supported by NASA through the MAVEN project.

Here we report on synoptic (or “disk”) observations of Martian discrete aurora in the extreme and far ultraviolet (

Water is lost from the Mars upper atmosphere to space as hydrogen and oxygen, both of which can be observed in scattered ultraviolet sunlight at 102.6 nm. We present Emirates Mars Mission Emirates Mars Ultraviolet Spectrometer (EMM/EMUS) insertion orbit observations of this airglow, resolving the independent altitude contributions of H and O for the first time. We present the first airglow modeling of the complete H and O 102.6 nm system and the first 3D azimuthally symmetric modeling of the O emission, retrieving temperatures and densities typical of northern spring. Our model reproduces the emission well above 200 km, but does not incorporate partial frequency redistribution needed to reproduce the observed O brightness at lower altitudes and on the disk. These results support future EMM/EMUS science orbit retrievals of H loss and the use of 102.6 nm observations to constrain planetary atmospheres across the solar system. UAE government; EMM/MBRSC; NASA through the MAVEN mission; KU-CU-LASP Space Sci. [8474000332] Published version Funding for development of the EMM mission was provided by the UAE government, and to co-authors outside of the UAE by MBRSC. Funding for the development of the radiative transfer model was provided by EMM/MBRSC and by NASA through the MAVEN mission. SR and KC are supported by the grant 8474000332-KU-CU-LASP Space Sci.

The Emirates Mars Ultraviolet Spectrometer (EMUS) instrument is one of three science instruments on board the “Hope Probe” of the Emirates Mars Mission (EMM). EMM arrived at Mars on February 9 2021, in order to explore the global dynamics of the Martian atmosphere, while sampling on both diurnal and seasonal timescales. The EMUS instrument is a far-ultraviolet imaging spectrograph, jointly developed by the Mohammed Bin Rashid Space Centre (MBRSC) in Dubai, UAE and the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder, which measures emissions in the spectral range 100-170 nm. Using a combination of its one-dimensional imaging and spacecraft motion, it makes two-dimensional far-ultraviolet images of the Martian disk and near-space environment including the Lyman beta and alpha atomic hydrogen emissions (102.6 nm and 121.6 nm), two atomic oxygen emissions (130.4 nm and 135.6 nm), and the carbon monoxide fourth positive group band emission (140-170 nm). Measurements of radiance at these wavelengths are used to derive the column abundance of atomic oxygen and carbon monoxide in the Martian thermosphere, and the density of atomic oxygen and atomic hydrogen in the Martian exosphere both with spatial and sub-seasonal variability. We will present a survey of results from EMM/EMUS including observed variability in atomic oxygen and carbon monoxide emission, two kinds of aurora, and the status of atmospheric retrievals.

The Mesosphere and Lower Thermosphere (MLT), at 80-100 km altitude, is critical in the coupling of the middle and upper atmosphere and determining momentum and energy transfer between these two regions. However, despite its importance, General Circulation Models (GCMs) have only recently been extended to the MLT region and remain poorly constrained.We use a long term meteor radar dataset from Rothera on the Antarctic Peninsula to test the eXtended Whole Atmosphere Community Climate Model (WACCM-X). This radar has been running continuously since 2005, resulting in a uniquely long, consistent measure of the winds in the MLT that we can use to investigate long term variability. We find that although some characteristic features are represented well in WACCM-X, the model exhibits considerable biases. In particular, the observations show a ~10m/s eastward wind in Antarctic winter whereas the model predicts winds of the same magnitude but opposite direction. We propose that this difference is due to the lack of secondary gravity wave modelling in WACCM-X.We also find interannual variability in both the observations and the model. In order to understand these differences, we further investigate the role of external climate processes in driving the winds in this region. Using a linear regression method, we quantify how the (observed and modelled) winds in the Antarctic MLT respond to Solar activity, the El Nino Southern Oscillation (ENSO), the Quasi-Biennial Oscillation (QBO) and the Southern Annular Mode (SAM). For some indices we find good agreement between the observations and model results while for others we see important differences.

The Emirates Mars Mission (EMM) – Hope Probe – was developed to understand Mars atmospheric circulation, dynamics, and processes through characterization of the Mars atmosphere layers and its interconnections enabled by a unique high-altitude (19,970 km periapse and 42,650 km apoapse) low inclination orbit that will offer an unprecedented local and seasonal time coverage over most of the planet. EMM has three scientific objectives to (A) characterize the state of the Martian lower atmosphere on global scales and its geographic, diurnal and seasonal variability, (B) correlate rates of thermal and photochemical atmospheric escape with conditions in the collisional Martian atmosphere, and (C) characterize the spatial structure and variability of key constituents in the Martian exosphere. The EMM data products include a variety of spectral and imaging data from three scientific instruments measuring Mars at visible, ultraviolet, and infrared wavelengths and contemporaneously and globally sampled on both diurnal and seasonal timescale. Here, we describe our strategies for addressing each objective with these data in addition to the complementary science data, tools, and physical models that will facilitate our understanding. The results will also fill a unique role by providing diagnostics of the physical processes driving atmospheric structure and dynamics, the connections between the lower and upper atmospheres, and the influences of these on atmospheric escape.

Introduction: The primary objective of this pilot study was to characterize human performance degradations caused by the pressurized Extravehicular Mobility Unit Spacesuit (EMU). Method: This study assessed maximum strength (force) for elbow flexion/extension and shoulder abduction/adduction for three EMU suit conditions. Results: Statistically significant differences were observed between suit conditions during elbow flexion. Differences of practical significant were observed between suit conditions for mean peak elbow flexion and extension, but not for shoulder abduction/adduction. EMU resistance to movement was found to differ based on the direction of movement. Discussion: Characteristics of the EMU spacesuit may reduce performance for some movements and improve performance for others.

Introduction: The objective of this project was to develop a comprehensive methodology to assess the suit fit and performance differences between a nominally sized extravehicular mobility unit (EMU) spacesuit and a nominal +1 (plus) sized EMU. Method: This study considered a multitude of evaluation metrics including 3D clearances and pressure point mapping to quantify potential issues associated with using off-nominal suit sizes. Results: There were minimal differences with using a plus suit size. Discussion: Analysis of the results indicates that future suit size evaluations should consider this ergonomic approach to understand and mitigate potential suit fit and performance issues.

This study draws from the divergent conclusions found in distance learning studies in general compared to those done within economics. Most studies of distance learning report no difference in learning outcomes compared to in class instruction. This is challenged by controlled studies within economics which report a negative difference in distance learning. Economics faculties who have taught the same undergraduate courses using both methods were surveyed. They perceive a learning advantage in onsite learning but not in learning outcomes. What explains this anomaly and what does it suggest about the growing use of distance learning in higher education? The survey suggests that differences in learning outcomes may reflect differences in evaluative techniques. This implies that distance and onsite learning are not perfect substitutes and suggests that learning tradeoffs must be managed. One example relates to faculty training on the importance of standardizing evaluative techniques.

NASA’s endeavors in human spaceflight rely on extensive volumes of human-systems integration requirements to ensure mission success. These requirements protect space hardware accommodation for the full range of potential crewmembers, but cannot cover every possible action and contingency in detail. This study was undertaken in response to questions from various strength requirement users who were unclear how to apply idealized strength requirements that did not map well to the complex loading scenarios that crewmembers would encounter. Three of the most commonly occurring questions from stakeholders were selected to be investigated by human testing and human modeling. Preliminary findings indicate that deviation from nominal postures can affect compliance with strength requirements positively or negatively, depending on the nature of the deviation. Human modeling offers some avenues for quickly addressing requirement verification questions, but is limited by the fidelity of the model and environment.

Space Human Factors Engineering (SHFE) researchers at Johnson Space Center (JSC), in collaboration with the Extravehicular Activity (EVA) Suit Team, performed a glove box study investigating operability of cursor controls, mobility, and strength of the participants while wearing pressurized gloves. Performance time was collected under a range of glove pressures (0, 0.8, 4.3, 6.3, and 8.1 psid), as well as bare-handed. Controls tested included a Castle switch, Rocker switch, and Trackball. The study was undertaken to determine impacts of operating controls under higher than nominal (i.e., > 4.3 psid) suit pressures. Operability when using cursor control devices was tested with an interactive software task representative of the types of actions that will be required to interact with space vehicle displays (display navigation and selection of a target). Results indicate that cursor control devices can be operated at pressures up to 8.1 psid, albeit with some difficulty. With respect to mobility, increased pr...

The purpose of the current study was to quantify finger tactility, while wearing a Phase VI Extravehicular Activity (EVA) glove. Subjects were fully suited in an Extravehicular Mobility Unit (EMU) suit. Data was collected under three conditions: bare-handed, gloved at 0 psi, and gloved at 4.3 psi. In order to test tactility, a series of 30 tactile stimuli (bumps) were created that varied in both height and width. With the hand obscured, subjects applied pressure to each bump until detected tactilely. The amount of force needed to detect each bump was recorded using load cells located under a force-plate. The amount of force needed to detect a bump was positively related to width, but inversely related to height. In addition, as the psi of the glove increased, more force was needed to detect the bump. In terms of application, it was possible to determine the optimal width and height a bump needs to be for a specific amount of force applied for tactility.

Current economic literacy tests focus on theory while almost totally ignoring the economy itself. This study analyzes how well we are teaching students empirical facts. Most agree that economic literacy is a laudable goal and current literacy pedagogy is centered on teaching students how to "think like economists." The authors do not intend to imply criticism to current literacy campaigns; rather this work is intended to open a discussion within the field about the need to also introduce students to some basic economic facts. This study is based upon surveys given to several hundred introductory economics students and tabulates some preliminary observations about their level of fact attainment.

This study was performed to aide in the creation of design requirements for the next generation of space suits that more accurately describe the level of mobility necessary for a suited crewmember through the use of an innovative methodology utilizing functional mobility. A novel method was utilized involving the collection of kinematic data while 20 subjects (10 male, 10 female) performed pertinent functional tasks that will be required of a suited crewmember during various phases of a lunar mission. These tasks were selected based on relevance and criticality from a larger list of tasks that may be carried out by the crew. Kinematic data was processed through Vicon BodyBuilder software to calculate joint angles for the ankle, knee, hip, torso, shoulder, elbow, and wrist. Maximum functional mobility was consistently lower than maximum isolated mobility. This study suggests that conventional methods for establishing design requirements for human-systems interfaces based on maximal isolated joint capabilities may overestimate the required mobility. Additionally, this method provides a valuable means of evaluating systems created from these requirements by comparing the mobility available in a new spacesuit, or the mobility required to use a new piece of hardware, to this newly established database of functional mobility.

This article argues that using either the SIC or NAICS one-digit classifications as a method of aggregating two- and three-digit time series data can ignore important regional characteristics. We present a pairwise cointegration approach of aggregation where the aggregated sectors can vary widely across regions. By systematically constructing region-specific sectors from more detailed industries, we find that the level of agglomeration across rural and urban areas can affect the composition and number of local sectors in a region. We use the results pointing to rural/urban geographic distinctiveness to further consider the Carlino and Defina (1998, 1999) finding that monetary policy has disparate effects across regions in the U.S.

PurposeTo test the economic theory that economies with greater stability and diversity are also economies that are more insulated from economic shocks.Design/methodology/approachUses persistence profiles derived from the cointegrated systems of two regional economies within the state of Oregon; the urban Portland Metropolitan Area (PMA) and the rural Southwest (SW) region.FindingsThe results of the above process illustrate that the more stable and diverse PMA responds with a smaller frequency and returns to equilibrium more quickly than the SW.Research limitations/implicationsThis paper only provides one set of observations, which is insufficient to prove the theory, but does enable a more extensive time series approach than that has been done previously. Also regional economies typically become more diversified over time, so the level of diversity can only be measured in relative terms not absolute.Practical implicationsThe paper reveals the benefits a diversified a diversified economy has in creating stable employment opportunities, as deviations in unemployment rates decline as diversification increases.Originality/valueThe paper takes a widely accepted time series econometrics technique from macroeconomic literature, cointegration, and applies it at a regional level. Cointegration combined with persistence profiles enables the integration of both the time dynamics of an economy and their inter‐industry linkages to be analyzed. This methodology dramatically increases the depth of possible analysis into the stability/diversity debate that has been waged over the last 70 years.

Evaluating regional industrial structures remains an inexact process as traditional aggregation schemes often lump superficially similar but behaviorally distinct industries together. We use pairwise cointegration methods to apply econometric criteria to aggregate detailed industries into behaviorally similar sectors. Based on these aggregations, cointegration guides the proper specification of a regional system to analyze the export versus local nature of core sectors. These methodologies are applied to Denver metropolitan data to demonstrate their utility. The findings indicate previous aggregation schemes are statistically inferior to those generated by this paper’s approach.

The gloved hand is one of an astronaut s primary means of interacting with the environment, and any restrictions imposed by the glove can strongly affect performance during extravehicular activity (EVA). Glove restrictions have been the subject of study for decades, yet previous studies have generally been unsuccessful in quantifying glove mobility and tactility. Past studies have tended to focus on the dexterity, strength, and functional performance of the gloved hand; this provides only a circumspect analysis of the impact of each type of restriction on the glove s overall capability. The aim of this study was to develop novel capabilities to provide metrics for mobility and tactility that can be used to assess the performance of a glove in a way that could enable designers and engineers to improve their current designs. A series of evaluations were performed to compare unpressurized and pressurized (4.3 psi) gloved conditions with the ungloved condition. A second series of evaluations were performed with the Thermal Micrometeoroid Garment (TMG) removed. This series of tests provided interesting insight into how much of an effect the TMG has on gloved mobility - in some cases, the presence of the TMG restricted glove mobility as much as pressurization did. Previous hypotheses had assumed that the TMG would have a much lower impact on mobility, but these results suggest that an improvement in the design of the TMG could have a significant impact on glove performance. Tactility testing illustrated the effect of glove pressurization, provided insight into the design of hardware that interfaces with the glove, and highlighted areas of concern. The metrics developed in this study served to benchmark the Phase VI EVA glove and to develop requirements for the next-generation glove for the Constellation program.

Across all fields of human-system interface design it is vital to posses a sound methodology dictating the constraints on the system based on the capabilities of the human user. These limitations may be based on strength, mobility, dexterity, cognitive ability, etc. and combinations thereof. Data collected in an isolated environment to determine, for example, maximal strength or maximal range of motion would indeed be adequate for establishing not-to-exceed type design limitations, however these restraints on the system may be excessive over what is basally needed. Resources may potentially be saved by having a technique to determine the minimum measurements a system must accommodate. This paper specifically deals with the creation of a novel methodology for establishing mobility requirements for a new generation of space suit design concepts. Historically, the Space Shuttle and the International Space Station vehicle and space hardware design requirements documents such as the Man-Systems Integration Standards and International Space Station Flight Crew Integration Standard explicitly stated that the designers should strive to provide the maximum joint range of motion capabilities exhibited by a minimally clothed human subject. In the course of developing the Human-Systems Integration Requirements (HSIR) for the new space exploration initiative (Constellation), an effort was made to redefine the mobility requirements in the interest of safety and cost. Systems designed for manned space exploration can receive compounded gains from simplified designs that are both initially less expensive to produce and lighter, thereby, cheaper to launch.