The tidal-rotational shape of the Moon and evidence for polar wander.

The origin of the Moon's large-scale topography is important for understanding lunar geology, lunar orbital evolution and the Moon's orientation in the sky. Previous hypotheses for its origin have included late accretion events, large impacts, tidal effects and convection processes. However, testing these hypotheses and quantifying the Moon's topography is complicated by the large basins that have formed since the crust crystallized. Here we estimate the large-scale lunar topography and gravity spherical harmonics outside these basins and show that the bulk of the spherical harmonic degree-2 topography is consistent with a crust-building process controlled by early tidal heating throughout the Moon. The remainder of the degree-2 topography is consistent with a frozen tidal-rotational bulge that formed later, at a semi-major axis of about 32 Earth radii. The probability of the degree-2 shape having both tidal-heating and frozen shape characteristics by chance is less than 1%. We also infer that internal density contrasts eventually reoriented the Moon's polar axis by 36 ± 4°, to the configuration we observe today. Together, these results link the geology of the near and far sides, and resolve long-standing questions about the Moon's large-scale shape, gravity and history of polar wander.

Teamwork facilitation and conflict resolution training in a HyFlex course during the COVID-19 pandemic.

Background: We evaluated the effect of three teaching strategies to facilitate teamwork in a systems analysis and design course during the COVID-19 pandemic: (1) offering a HyFlex version of the course, (2) facilitating scheduled online teamwork sessions for all students, and (3) providing conflict resolution training to help teams overcome collaboration challenges. Purpose/Hypothesis: To identify the impact of these instructional strategies and answer four research questions, we measured (1) performance, dynamics, and cooperation strategies of teams and (2) students' perceptions of their own and team members' performance along with changes in their perceptions of their conflict management skills. Design/Method: We used a simultaneous triangulation mixed-methods design to obtain distinct but complementary qualitative and quantitative data. We compared data from two offerings of the course: Fall 2019 and Fall 2020 semesters. In the Fall 2019 semester, an in-person active learning strategy was used, while in the Fall 2020 semester, the course followed a HyFlex delivery mode due to the COVID-19 pandemic. Results: Findings suggest that the use of cooperative learning pedagogy along with HyFlex accommodations for safety and social distancing requirements for the Fall 2020 semester provided students with a comparable learning experience to a traditional in-person mode. Conclusions: Learning strategies, pedagogical supports, and teamwork training can enhance social interactions, and consequently, students' social presence in online learning. Conflict resolution training could be a valuable tool for improving teamwork skills and communication among team members.

Students in Fully Online Programs Report More Positive Attitudes toward Science Than Students in Traditional, In-Person Programs.

Following the growth of online, higher-education courses, academic institutions are now offering fully online degree programs. Yet it is not clear how students who enroll in fully online degree programs are similar to those students who enroll in in-person ("traditional") degree programs. Because previous work has shown students' attitudes toward science can affect their performance in a course, it is valuable to ask how attitudes toward science differ between these two populations. We studied students who completed a fully online astrobiology course. In an analysis of 451 student responses to the Classroom Undergraduate Research Experience survey, we found online program students began the course with a higher scientific sophistication and a higher sense of personal value of science than those in traditional programs. Precourse attitudes also showed some predictive power of course grades among online students, but not for traditional students. Given established relationships between feelings of personal value, intrinsic motivation, and, in turn, traits such as persistence, our results suggest that open-ended or exploration-based learning may be more engaging to online program students due to their pre-existing attitudes. The converse may also be true, that certain pre-existing attitudes among online program students are more detrimental than they are for traditional program students.