Scott Sommerfeldt Elected ASA President

Rocket launches generate acoustic environments that impact nearby communities, motivating the need for tools to predict launch noise at the community level. RUMBLE is a computational rocket noise prediction model that produces spatial predictions of acoustic metrics but offers limited temporal resolution, complicating direct comparison with field measurements. This paper tests whether RUMBLE-predicted unweighted maximum sound levels (Lmax) agree with community-level measurements from nine Falcon 9 Block 5 launch events recorded near Cape Canaveral, Florida. Field measurements were obtained using Larson–Davis sound level meters deployed at residential distances of approximately 20–25 km from active launch pads. Because RUMBLE outputs only scalar metrics without time histories, a rolling Lmax analysis using Z-weighting and slow exponential time weighting was developed to enable direct comparison. Across nine launch events, RUMBLE-predicted Lmax values agreed with measured community levels within 5 dB, with mean absolute differences of 3.5 dB for Space Launch Complex 40 operations and 2.8 dB for Launch Complex 39A operations. These results demonstrate that Lmax is an effective scalar metric for validation of RUMBLE predictions at community locations. While the absence of time-domain and spectral outputs limits more detailed comparisons, the results provide a foundation for future model development and monitoring efforts.

It is inherently challenging to characterize long-period transiting exoplanets because the transit events are rare and last long. These systems provide unique insights into planetary formation, migration, the detection of exomoons, and primordial atmospheres by occupying a sparsely populated region of the exoplanet parameter space, however. The complexity increases further for long-period planets near mean-motion resonances, where transit timing variations (TTVs) can reach amplitudes of several hours to days. We present a coordinated space- and ground-based observing campaign using photometry from NEOSSat, multiple LCOGT sites, MuSCAT, MuSCAT3, Tierras, and NGTS to capture the 19-hour transit of the long-period giant exoplanet HIP 41378f (P ≈ 542 d, R ≈ = 9.5 R⊕) on 31 October 2025. Our transit analysis constrains the time of inferior conjunction to TC = 2460980.888 ± 0.029 BJDTDB, occurring ∼ 7 hours earlier than predicted from its linear ephemeris. This significant offset is consistent with the previously reported TTVs of HIP41378f, confirming it as the longest-period exoplanet known to exhibit measurable TTVs. By combining this new precise measurement with the transit timings of the two outer planets in the system (HIP41378d and HIP41378e), we performed a dynamical modeling of the system using the N-body integrator TRADES, refined the ephemeris of HIP41378f, and predict future transit events for all three outer transiting planets.

With the great success of stellar occultations in probing trans-Neptunian objects (TNOs), these observations have become ubiquitous, leading to significant advances in our knowledge of TNOs. As stellar occultation predictions have improved, it has become feasible to predict and observe stellar occultations by satellites of TNOs. In this work, we develop a robust methodology for predicting occultations by large TNO satellites based on the most up-to-date and accurate ephemerides available. We validated our methodology by reproducing several previously recorded occultations by Hi‘iaka, and then used it to predict—and successfully observe—stellar occultations of two other satellites, Namaka and Tinia. As a demonstration of the scientific return of such occultations, we provide the detailed prediction, observation, and analysis of the Tinia occultation. For the satellite of Uni (2002 UX25), we recorded two positive occultation chords that yielded projected circular and elliptical profiles with equivalent diameters of 180.8 ± 0.6 and 193.0 ± 1.0 km, respectively. Using the published absolute magnitude for the system and Tinia’s relative brightness with respect to the primary, we derived an absolute magnitude of HV = 6.476 ± 0.183 mag for Tinia. This corresponds to geometric albedo values of ρV = 0.139 ± 0.023 and ρV = 0.122 ± 0.02 for circular and elliptical solutions, respectively. Under the assumption of equal albedos, we obtained a diameter of D = 571 ± 53 km and D = 610 ± 53 km for the primary. Our methods provide a precise, simple, open-source technique for predicting TNO satellite occultations, enabling diverse investigations into the properties of TNOs and their satellites as demonstrated for Tinia.

Magnetic pyrochlores with non-Kramers rare-earth ions provide a platform for exploring emergent gauge physics and quantum spin-ice behavior, yet the influence of structural disorder on their ground states remains insufficiently understood. Here we combine bulk characterization and single-crystal neutron-scattering measurements to investigate the non-Kramers pyrochlore Pr2Sn2O7. At temperatures below ∼1 K, the system exhibits key hallmarks of quantum spin-ice physics, including anisotropic spin-ice correlations and two distinct dynamical timescales. Upon further cooling, however, we observe a complete spin-freezing transition at Tf≈0.15 K, accompanied by recovery of the full nuclear Schottky anomaly, the emergence of a gapped magnetic excitation, and the development of incipient (100) magnetic correlations. Comparison with related Pr-based pyrochlores places Pr2Sn2O7 near the spin-frozen boundary of a disorder-perturbed phase diagram. These results establish a disorder-driven framework for the evolution of quantum spin-ice behavior into frozen ground states, revealing how signatures of a proximate quantum spin liquid can persist despite disorder-induced spin freezing in non-Kramers pyrochlores.

Acoustic beamforming is widely used for source localization and line-of-bearing determination. Although many different beamforming techniques have been formulated, atmospheric turbulence effects on acoustic arrays are usually ignored in both their theoretical formulation and practical implementation. As a result, the performance of conventional beamformers, formulated for a non-turbulent atmosphere, degrades in the presence of wind velocity and temperature fluctuations, which cause fluctuations in the received signal amplitude and phase. This article presents a mathematical framework in which the amplitude and phase fluctuations are effectively suppressed from the signals allowing application of any beamforming technique and mitigating its performance degradation in a turbulent atmosphere. The framework is constrained to a single source and by the monochromatic plane wave approximation. Application of such an approach to an experiment revealed that the phase and amplitude fluctuations with spatial scales smaller than the array aperture are successfully suppressed, but the larger fluctuations (resulting in wavefront random tilt) remain and cause errors in the line of bearing estimates.

High-density multielectrode arrays (HD-MEAs) generate large, complex datasets that are challenging to efficiently manage and analyze with existing tools, especially in open-source environments. To address this, we developed the BYU Seizure and Analytics Tool (YSA), an open-source graphical user interface built in Python and C++ for efficient analysis and visualization of HD-MEA recordings. The YSA features raster plots, automated discharge detection and tracking, downsampling, playback, and export functions, enabling streamlined workflows for large-scale neural data. We demonstrate the utility of the tool in the context of seizure and status epilepticus-like activity, highlighting how the YSA facilitates rapid exploration of the spatiotemporal dynamics in brain networks. This platform provides an accessible and practical solution for HD-MEA data analysis, supporting a range of neuroscience applications.