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Abstract At the end of its mission, the MESSENGER spacecraft's orbit intersected Mercury's nightside magnetic equator at low altitudes below 420 km, enabling the first in situ observations of this region, where the magnetic field strength is typically sub‐dipolar. We present 5 events from these orbits where MESSENGER encountered Earth‐like dipolarization regions characterized by enhanced field strengths up to 20 nT above the intrinsic planetary field, and an average decrease and increase in plasma proton density and temperature, respectively, for 1–2 min periods, comparable to Hermean substorm timescales. The events span local times of 1.5 hr pre‐ and post‐midnight, and are present from the magnetic equator up to magnetic latitudes of at least north. Supported by estimates of decreased flux tube entropy during these events, we suggest these dipolarization regions are formed by the pileup of dipolarization fronts and formation of a substorm current wedge. 

Abstract Ion impacts on airless bodies such as Mercury alter their surfaces and contribute to their exospheres via sputtering. Their exact contribution in comparison to other effects is still uncertain, but observations by the MESSENGER spacecraft largely indicated influences from micrometeoroids. In this paper, we present an updated modeling of sputtering at Mercury to help estimate the role of sputtering at average solar wind conditions. To achieve this, we account for ion precipitation due to the planet's magnetosphere and for the presence of a porous regolith: We combine H⁺and He⁺⁺fluxes to the surface from the Amitis hybrid model with sputter yields derived from a regolith simulation in SDTrimSP‐3D. We find that H⁺and He⁺⁺show similar precipitation patterns, but H⁺energies are much more reduced and variable than those of He⁺⁺. Globally, H⁺and He⁺⁺contribute about equal amounts of sputtering. Our laboratory‐calibrated sputter yields are significantly lower than estimates used in previous studies, resulting in a global sputtering source of around 10²³atoms s⁻¹. Specifically for Ca and Mg exospheres we find source rates from sputtering that are largely unaffected by Mercury's seasonal orientation and too small by up to around two orders of magnitudes to explain MESSENGER observations. This supports a micrometeoroid‐impact‐dominated source of refractory elements. We find, however, that this is an effect of the reduced magnetospheric precipitation at Mercury. At other bodies such as the Moon, a different regime should be prevalent and sputtering should contribute at least similarly to the exospheres of refractory elements. 

The use of multimodal data allows excellent opportunities for human–computer interaction research and novel techniques regarding virtual and augmented reality (VR/AR) experiences. Collecting, coordinating, and synchronizing a large amount of data from multiple VR/AR hardware while maintaining a high framerate can be a daunting task, despite the compelling nature of multimodal data. The Lab Streaming Layer (LSL) is an open-source framework that enables the synchronous collection of various types of multimodal data, unlike existing expensive alternatives. However, despite its potential, this framework has not been fully adopted by the VR/AR research community. In this paper, we present a guideline of the LSL framework’s use in VR/AR research as well as report current trends by performing a comprehensive literature review on the subject. We extract 549 publications using LSL from January 2015 to March 2022. We analyze types of data, displays, and targeted application areas. We describe in-depth reviews of 38 selected papers and provide use of LSL in the VR/AR research community while highlighting benefits, challenges, and future opportunities. 

Designing a senior-level course that involves problem-based learning, including project completion task, is laborious and challenging. A well-designed project motivates the students to be self-learners and prepares them for future industrial or academic endeavors. The COVID-19 pandemic brought many challenges when instructions were forced to move either online or to a remote teaching/learning environment. Due to this rapid transition, delivery modes in teaching and learning modalities faced disruption making course design more difficult. The senior level Flight Controls course AME - 4513 is designed with Unmanned Aerial Systems (UAS) related projects for the students to have a better understanding of UAS usage on various applications in support of Advanced Technological Education (ATE) program. The purpose of this paper is to present the UAS lab modules in a junior level robotics lab, AME - 4802, which preceded the Flight Controls course in the school of Aerospace and Mechanical Engineering at the University of Oklahoma. Successfully completing the course project requires independent research and involves numerical simulations of UAS. The Robotics Lab course focuses on hands-on projects of robotic systems with an emphasis on semi-autonomous mobile robots, including an UAS introduction module. - The UAS module in the Robotics Lab class is introduced in Spring 2020. Therefore, most of the students enrolled in the Spring 2020 Robotics Lab course have introductory knowledge about the UAS system when taking the Fall 2020 Flight Control course. In addition, Spring 2020 Robotics Lab was affected due to COVID-19. - The UAS module was not introduced in 2019 Spring Robotics lab. Thus, the students enrolled in Fall 2019 Flight Controls course did not have prior knowledge on the UAS system. - We thus present the implementation of UAS module in a junior level robotics lab which preceded the senior level Flight Controls course in following Fall semester, when the same instructor taught the course.