Scott Sommerfeldt Elected ASA President

Two essential points of consideration for spherical directivity measurements are the measurement radius and the sound source's location relative to the evaluation surface. When spatial constraints, such as anechoic chamber size, limit the measurement radius, both points may lead to measured near-field directivity patterns deviating from the desired far-field radiation characteristics. To clarify the impact of source placement on near-field and far-field radiation patterns, this work develops far-field magnitude and phase relations between untranslated and translated sources. The resulting theory shows that far-field propagation via acoustical holography is sufficient to correct for source-positioning uncertainties, provided that the measurements incorporate sufficient sampling positions to avoid spatial aliasing. The magnitude equivalence of translated and untranslated far-field directivity patterns also enables an acoustic centering procedure that overcomes previous low-frequency limitations.

The Falcon 9 Block 5 is the world's most frequently launched orbital rocket, with 165 launches in 2025 alone. This cadence enables robust characterization of launch noise from repeated field measurements. This study analyzes 548 acoustic measurements from 76 Falcon 9 launches at Vandenberg Space Force Base (VSFB), spanning pad-to-station distances from approximately 230 m to 30 km. Mixed-effects models are developed to describe maximum sound level (⁠ 

⁠) and sound exposure level (SEL), including A- and C-weighted metrics, as functions of distance. Variability is modeled using a power-law variance structure, revealing increasing heteroskedasticity with distance. Prediction intervals derived from this structure quantify the range of expected individual measurements. Comparisons with Starship Super Heavy Flight 6 and launches from Florida suggest the model form is broadly applicable, though coefficients vary by vehicle. Additional analyses examine seasonal, diurnal, and terrain effects. Seasonal and diurnal effects are small for the present dataset, whereas terrain shielding can produce systematic reductions in level. Overall, this work provides a statistically grounded description of Falcon 9 launch noise and its variability and establishes a measured reference dataset for evaluation and future development of launch-noise prediction models.

When rockets ascend, accelerate, and pitch over toward orbit, they can generate sonic booms audible on the ground over 100 km from the launch site, as observed with recent launches from Vandenberg Space Force Base. The locations where these booms arrive vary seasonally, with some areas experiencing them only at certain times of year. In this paper, the seasonal variation is explored and modeled using pcboom 7.5.0, with simulations run using measured and modeled weather profiles from 2020 to 2025. pcboom peak overpressure footprints were interpolated to four locations where sonic booms have been reported and measured: Carpinteria, Ojai, Ventura, and Oxnard. The probability of a sonic boom occurring at each location was higher in the winter and lower in the summer (all seasons defined in the northern hemisphere). Changes in the footprint location were linked to seasonal changes in weather. Specifically, the changes in upper-level winds (stratospheric and mesospheric) influenced large changes in the land area that received a sonic boom. Strategic seasonal launch scheduling for missions should be considered to enable launches along all azimuths while minimizing the occurrence of sonic booms on land.

We characterize the radius-dependent observed transiting eccentricity distribution of 219 warm (P = 8–50 days) systems with only one transiting planetary candidate identified during Sectors 1–69 of the Transiting Exoplanet Survey Satellite (TESS) mission. Using the “photoeccentric effect” in a hierarchical Bayesian framework, we first model the population using discrete planetary size bins (sub-Neptunes, sub-Saturns, and Jovians). We then develop a continuous mixture model with weights governed by a logistic sigmoid function of radius. We find that the warm-single population is best described by two components: a dominant low-eccentricity mode (〈elow〉 = ) and a secondary dynamically excited mode (〈ehigh〉 = ). The fraction of planets belonging to this high-eccentricity component increases strongly with planet radius, characterized by a transition at a break radius of Rbr = R⊕. This trend places warm sub-Saturns predominantly on the same low-eccentricity track as sub-Neptunes. In contrast, warm Jovians (8–16 R⊕) are frequently eccentric, with  of the population in the high-eccentricity mode. Under the assumption of a two-component model, we see tentative evidence for a bimodal Jovian distribution at ∼2.7σ. Finally, we identify a nonnegligible tail of highly eccentric sub-Neptunes (1–4 R⊕), which comprise  of the population, consistent with excitation by nontransiting external companions.

Particulate contamination requires dust mitigation techniques to provide low-scatter surfaces on sensitive instrumentation in space. We have shown that poly(olefin sulfone)s photodegrade under spacelike conditions: in vacuum and with UV light exposure. We now demonstrate that photodegradable polymers can reduce dust accumulation on optical surfaces for space applications. This investigation shows that the dissociative degradation of poly(olefin sulfone)s significantly decreased the number of dust particles on a dust-coated surface. These results suggest a powerful way to mitigate the collection of extraterrestrial dust on optical surfaces in space, enabling passive removal of particulate contamination without any direct human intervention.

Protein function emerges from dynamic conformational changes, yet structure prediction methods provide only static snapshots. While AlphaFold3 (AF3) predicts protein structures, the potential for extracting dynamic information from its ensemble predictions has remained underexplored. Here, we demonstrate that AF3 structural ensembles contain substantial dynamic information that correlates remarkably well with molecular dynamics simulations (MD). We developed ChronoSort, a novel algorithm that organizes static structure predictions into temporally coherent trajectories by minimizing structural differences between neighboring frames. Through systematic analysis of four diverse protein targets, we show that root-mean-square fluctuations derived from AF3 ensembles can correlate strongly with those from MD (r = 0.53 to 0.84). Principal component analysis reveals that AF3 predictions capture the same collective motion patterns observed in molecular dynamics trajectories, with eigenvector similarities significantly exceeding random distributions. ChronoSort trajectories exhibit structural evolution profiles comparable to MD. These findings suggest that modern AI-based structure prediction tools encode conformational flexibility information that can be systematically extracted without expensive MD. We provide ChronoSort as open-source software to enable broad community adoption. This work offers a novel approach to extracting functional insights from structure prediction tools in minutes, with significant implications for synthetic biology, protein engineering, drug discovery, and structure–function studies.