News and Events

Thumbnail of ISS Meets Saturn
This month, bright planet Saturn rises in evening skies, its rings oriented nearly edge-on when viewed from planet Earth. And in the early morning hours on July 6, it posed very briefly with the International Space Station when viewed from a location in Federal Way, Washington, USA. This well-planned image, a stack of video frames, captures their momentary conjunction in the same telescopic field of view. With the ISS in low Earth orbit, space station and gas giant planet were separated by almost 1.4 billion kilometers. Their apparent sizes are comparable but the ISS was much brighter than Saturn and the ringed planet's brightness has been increased for visibility in the stacked image. Precise timing and an exact location were needed to capture the ISS/Saturn conjunction.
Mount Timpanogos with sky above
Temp:  87 °FN2 Boiling:75.9 K
Humidity: 24%H2O Boiling:   368.4 K
Pressure:85 kPaSunrise:6:12 AM
Sunlight:81 W/m²   Sunset:8:53 PM
Image for New Weather Station
A group of undergraduate students braved the heat and heights of the ESC roof to install a new weather station. The station is up and running, and will hopefully record data for years to come.
Image for Study analyzes distant Kuiper Belt object with NASA's Hubble data
Using data from NASA's Hubble Space Telescope, a new study suggests that an object previously thought to be a binary system may be a rare triple system of orbiting bodies.
Image for BYU’s Rising Astronomers Take Center Stage at the Winter AAS Conference
In early January 2025, a group of 16 students from Brigham Young University’s Physics & Astronomy Department showcased their research at the prestigious American Astronomical Society (AAS) in National Harbor, Maryland.
Image for Acoustics group studies the roar of SpaceX's Starship
Acoustics faculty and students measure the thunderous noise of the world’s most powerful rocket, exploring its impact on communities and the environment.

Selected Publications

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Jason Meziere, Brayden Bekker, Hayden Oliver, Luke Cvetko, and Gus L.W. Hart (et al.)

Understanding the atomic structure of precipitate phases in shape memory alloys is critical to determining their structure–property relationships and developing high-performance shape memory alloys. However, experimental methods are limited in determining atomic configurations in cases where the number of atoms per unit cell is very high, or the phase is small (few nms). While density functional theory (DFT) can aid in the accurate determination of a phase’s crystallography, this is challenged by the number of candidate structures. Recently, a cubic phase was discovered during the heat treatment of a Hf-Ni-Ti alloy developed with improved tribological applications and rolling contact fatigue. We use DFT, machine learned interatomic potentials (MLIPs), and a genetic algorithm to identify likely configurations for the cubic phase. Likely candidate structures consistent with experimentally determined structural information were identified. Limitations of experimental microscopy methods, crystal simulation, and DFT-MLIP techniques are discussed.

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We analyze three nearby spiral galaxies—NGC 1097, NGC 1566, and NGC 3627—using images from the DustPedia database in seven infrared bands (3.6, 8, 24, 70, 100, 160, and 250 μm). For each image, we perform photometric decomposition and construct a multi-component model, including a detailed representation of the spiral arms. Our results show that the light distribution is well described by an exponential disk and a Sérsic bulge when non-axisymmetric components are properly taken into account. We test the predictions of the stationary density wave theory using the derived models in bands, tracing both old stars and recent star formation. Our findings suggest that the spiral arms in all three galaxies are unlikely to originate from stationary density waves. Additionally, we perform spectral energy distribution (SED) modeling using the hierarchical Bayesian code HerBIE, fitting individual components to derive dust properties. We find that spiral arms contain a significant (>10%) fraction of cold dust, with an average temperature of approximately 18–20 K. The estimated fraction of polycyclic aromatic hydrocarbons (PAHs) declines significantly toward the galactic center but remains similar between the arm and interarm regions.

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X-ray reverberation mapping is a powerful technique for probing the innermost accretion disk, whereas continuum reverberation mapping in the UV, optical, and infrared (UVOIR) reveals reprocessing by the rest of the accretion disk and broad-line region (BLR). We present the time lags of Mrk 817 as a function of temporal frequency measured from 14 months of high-cadence monitoring from Swift and ground-based telescopes, in addition to an XMM-Newton observation, as part of the AGN STORM 2 campaign. The XMM-Newton lags reveal the first detection of a soft lag in this source, consistent with reverberation from the innermost accretion flow. These results mark the first simultaneous measurement of X-ray reverberation and UVOIR disk reprocessing lags—effectively allowing us to map the entire accretion disk surrounding the black hole. Similar to previous continuum reverberation mapping campaigns, the UVOIR time lags arising at low temporal frequencies are longer than those expected from standard disk reprocessing by a factor of 2–3. The lags agree with the anticipated disk reverberation lags when isolating short-timescale variability, namely timescales shorter than the Hβ lag. Modeling the lags requires additional reprocessing constrained at a radius consistent with the BLR size scale inferred from contemporaneous Hβ-lag measurements. When we divide the campaign light curves, the UVOIR lags show substantial variations, with longer lags measured when obscuration from an ionized outflow is greatest. We suggest that, when the obscurer is strongest, reprocessing by the BLR elongates the lags most significantly. As the wind weakens, the lags are dominated by shorter accretion disk lags.

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Joshua Ebbert, Bryce Hedelius, Jyothish Joy, Daniel H. Ess, and Dennis Della Corte

TrIP2 is an advanced version of the transformer interatomic potential (TrIP) trained on the expanded ANI-2x data set, including more diverse molecular configurations with sulfur, fluorine, and chlorine. It leverages the equivariant SE(3)-transformer architecture, incorporating physical biases and continuous atomic representations. TrIP was introduced as a highly promising transferable interatomic potential, which we show here to generalize to new atom types with no alterations to the underlying model design. Benchmarking on COMP6 energy and force calculations, structure minimization tasks, torsion drives, and applications to molecules with unexpected conformational energy minima demonstrates TrIP2’s high accuracy and transferability. Direct architectural comparisons demonstrate superior performance against ANI-2x, while holistic model evaluations─including training data and level-of-theory considerations─show comparative performance with state-of-the-art models like AIMNet2 and MACE-OFF23. Notably, TrIP2 achieves state-of-the-art force prediction performance on the COMP6 benchmarks and closely approaches DFT-optimized structures in torsion drives and geometry optimization tasks. Without requiring any architectural modifications, TrIP2 successfully capitalizes on additional training data to deliver enhanced generalizability and precision, establishing itself as a robust and scalable framework capable of accommodating future expansions or applications to new domains with minimal reengineering.

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Sharisse Poff, Benjamin Boyack, Robert C. Davis, and Shiuh-hua Wood Chiang (et al.)

Pulsatile bioimpedance measurements require filters with very narrow bandwidths to preserve heartbeat-rate modulation while suppressing excess noise. At the signal's carrier frequency, this demands an impractically-high-Q filter. Multirate signal processing is an attractive solution to this problem, as it provides an avenue to extract the signals of interest practically. This paper presents a multirate filtering solution and shows step-by-step how the bioimpedance data of interest are extracted from noise and excitation frequency in in-phase and quadrature signals acquired from an analog measurement circuit. The tested impedance values resemble realistic human tissue impedance, demonstrating the method's ability to measure a human pulse within an approximately 50−Hz bandwidth at a 1−MHz carrier. This method is useful for high-Q bioimpedance measurements where interest lies in the details of signals pulsing at the rate of a beating human heart.

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Matthew G. Yancey, Griffin Houston, Grant W. Hart, Logan T. Mathews, Michael S. Bassett, J. Taggart Durrant, and Kent L. Gee

The Firefly Alpha launch, featuring an unexpected engine shutdown, offered a unique opportunity to study the acoustic effects of clustered nozzles on rocket noise. Measurements revealed a 0.75 dB drop in overall sound pressure levels (OASPL) and a 30% frequency shift, compared to predictions of 1.2 dB and 20%, respectively. While direct comparisons are limited by the dataset’s uniqueness, the results generally align with existing rocket noise models, highlighting areas for refinement. This study provides valuable data for improving noise prediction methods and deepening the understanding of launch vehicle acoustics.