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Abstract The Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) provides continuous global maps of Birkeland currents, using magnetic field perturbations (dB) obtained by calibrating and detrending data from engineering magnetometers on the 66 polar‐orbiting Iridium satellites in the communications constellation. Here, we provide an assessment of AMPERE dBaccuracy, as compared with magnetic field observations from the Swarm satellite mission. The CHAOS v8.1 model (Finlay et al., 2020,https://doi.org/10.1186/s40623‐020‐01252‐9) was used to remove the main field and other non‐ionospheric contributions from both data sets. In a nearest‐neighbor comparison covering August 2022, AMPERE's calibrated and detrended dBdata from the Iridium NEXT satellites are found to have root‐mean‐square deviations of 31 and 33 nT (for dB_θand dB_φ, respectively) as compared with data from Swarm, while the biases are −7 and −2 nT. For the same interval, AMPERE's fitted maps have root‐mean‐square errors of <40 nT, rising to 109–185 nT in active conditions (defined as Swarm dB > 250 nT). However, there is evidence that small scale (<400‐km along Swarm track direction) dBstructures are not fully resolved. Overall, we find that the AMPERE dBdata and fitted products are unbiased and are typically in excellent agreement with the Swarm data. 

Non-acceptance of biological evolution is prevalent in U.S. adults and is highly correlated with both religiosity and perceptions of conflict with religious beliefs. Instructors teaching evolution at religiously affiliated institutions may be uniquely situated to increase evolution acceptance by being perceived as culturally in-group by religious students. We measured student evolution acceptance, perception of conflict, and perceptions of instructor religiosity in courses on evolution and related fields at a religiously affiliated university, and if these perceptions influenced student attitudes. We found no significant change in acceptance, but did find differences between students enrolled in Teacher Education and Science courses. 

Disparities in undergraduate STEM degree completions across the United States are a national concern. Undergraduate-level research opportunities are vital for developing future researchers and building their scientific identity. These experiences can help students in community colleges acquire 21st-century skills and build confidence in their ability to do science [1-3]. The development and implementation of guided research experiences provide users with a topic they are familiar with but not necessarily experts in, like SARS-CoV2 infections. In this particular study, the Immune Epitope Database (IEDB) was used to identify amino acid residues located on the immunogenic regions of the spike glycoprotein of SARS-CoV-2 variants: Alpha, Beta, Gamma, Delta, and Omicron. IEDB is a web-based bioinformatics tool that contains published epitope information and prediction aids that can be used as a research platform for studying infectious diseases. The objective of this study aimed to map the immunogenic regions on the spike glycoproteins of the SARS-CoV-2 variants and predict the immune evasion of these variants [4-6]. Identifying the antigenic determinations that bind to the antibodies is essential for designing future candidates for peptide-based vaccines. This study aims to map the immunogenic regions on the spike glycoproteins of the SARS-CoV-2 variants and predict the immune evasion of these variants [4-6]. Identifying the antigenic determinations that bind to the antibodies is essential for designing future candidates for peptide-based vaccines. This research identifies regions where mutations have occurred in the virus, which are important to study as they can affect the virus’s immune evasion and impact available vaccines. Targeting multiple immunogenic regions unaffected by mutations can serve as potential targets for new vaccines, providing better protection against different variants. 

Abstract We comprehensively analyzed geomagnetic perturbations using ground magnetic records from over 400 stations spanning four solar cycles, from 1976 to 2023. We assess the perturbations in the three magnetic components separately. Our study covers low, middle, and high magnetic latitudes in the northern magnetic hemisphere, with the primary objective of quantifying extreme values and evaluating their variability on magnetic latitude, local time, and solar cycle phases “minimum, ascending, maximum, and declining.” Our findings reveal spatial patterns to be less discernible as perturbations intensify, with distinct responses at middle and high latitudes. The extreme values, defined as percentiles 0 and 100, were observed to be localized and randomly distributed in local time, especially in the east magnetic component. Additionally, we observed dusk‐dawn asymmetries in the magnitude of perturbations related to the auroral electrojets, indicating complex interactions between the magnetosphere and ionosphere. Furthermore, the results reveal a preference for the most significant extreme values to occur in the declining phase of the solar cycle. These insights deepen our understanding of geomagnetic perturbations and their variability, contributing to space weather forecasting and mitigation strategies. 

Abstract We investigate a 15‐day period in October 2011. Auroral observations by the Special Sensor Ultraviolet Spectrographic Imager instrument onboard the Defense Meteorological Satellite Program F16, F17, and F18 spacecraft indicate that the polar regions were covered by weak cusp‐aligned arc (CAA) emissions whenever the interplanetary magnetic field (IMF) clock angle was small, |θ| < 45°, which amounted to 30% of the time. Simultaneous observations of ions and electrons in the tail by the Cluster C4 and Geotail spacecraft showed that during these intervals dense (≈1 cm⁻³) plasma was observed, even as far from the equatorial plane of the tail as |Z_GSE| ≈ 13R_E. The ions had a pitch angle distribution peaking parallel and antiparallel to the magnetic field and the electrons had pitch angles that peaked perpendicular to the field. We interpret the counter‐streaming ions and double loss‐cone electrons as evidence that the plasma was trapped on closed field lines, and acted as a source for the CAA emission across the polar regions. This suggests that the magnetosphere was almost entirely closed during these periods. We further argue that the closure occurred as a consequence of dual‐lobe reconnection. Our finding forces a significant re‐evaluation of the magnetic topology of the magnetosphere during periods of northwards IMF. 

We present a statistical analysis of the occurrence of bifurcations of the Region 2 (R2) Field-Aligned Current (FAC) region, observed by the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE). Previously, these have been shown to occur as the polar cap contracts after substorm onset, the beginning of the growth phase. During this phase both the Region 1 (R1) and R2 currents move equatorwards as the polar cap expands. Following onset, the R1 FAC region contracts polewards but the R2 FAC continues to expand equatorwards before eventually fading. At the same time, a new R2 FAC develops equatorwards of the R1 FAC. We have proposed that the bifurcated FACs formed during substorms are associated with plasma injections from the magnetotail into the inner magnetosphere, and that they might be the FAC signature associated with Sub-Auroral Polarization Streams (SAPS). We investigate the seasonal dependence of the occurrence of bifurcations from 2010 to 2016, determining whether they occur predominantly at dawn or dusk. Region 2 Bifurcations (R2Bs) are observed most frequently in the summer hemisphere and at dusk, and we discuss the possible influence of ionospheric conductance. We also discuss a newly discovered UT dependence of the R2B occurrences between 2011 and 2014. This dependence is characterized by broad peaks in occurrence near 09 and 21 UT in both hemispheres. Reasons for such a preference in occurrence are explored.