Results 41 to 50 of about 382 (187)

CLASSIFICATION OF BOLIDES AND METEORS IN DOPPLER RADAR WEATHER DATA USING UNSUPERVISED MACHINE LEARNING [PDF]

, 2019
This thesis presents a method for detecting outlier meteors and bolides within Doppler radar data using unsupervised machine learning. Principal Component Analysis (PCA), k-means Clustering, and t-Distributed Statistical Neighbor Embedding (t-SNE ...
Smeresky, Brendon P.
core  

Seismic Recovery of Acoustic Source Height During the OSIRIS-REx Sample Return Capsule Re-Entry

The Seismic Record
Controlled hypersonic reentries with well-constrained trajectories are exceedingly rare, yet they provide valuable reference cases for validating geophysical source characterization methods applicable to bolides and space debris. The 24 September 2023 re-
Elizabeth A. Silber, Logan T. Scamfer
doaj   +1 more source

Correlating High‐Resolution Terrestrial Organic Carbon Isotope Records Across the Cretaceous‐Paleogene Boundary

Paleoceanography and Paleoclimatology, Volume 41, Issue 7, July 2026.
Abstract The Cretaceous–Paleogene boundary (∼66 million years ago) represents the most recent mass extinction event when an estimated 75% of all species became extinct, including all non‐avian dinosaurs. Here we focus on the stable carbon isotope (δ13C) analysis of coal and coaly sediments across the terrestrial K/Pg boundary from 10 sites, between 42 ...
Gregory D. Price, Rhodri M. Jerrett, Lauren K. O'Connor, Emily Dearing Crampton‐Flood, Bart E. van Dongen, Sabine K. Lengger, Marc Davies   +6 more
wiley   +1 more source

Methane from UV-irradiated carbonaceous chondrites under simulated Martian conditions [PDF]

, 2012
A UV photolytic process was studied for the production of methane from carbonaceous chondrites under simulated Martian conditions. Methane evolution rates from carbonaceous chondrites were found to be positively correlated to temperature (−80 to 20°C ...
Britt, Daniel T., Barlow, Nadine G., Schuerger, Andrew C., Clausen, Christian A., Moores, John E.   +4 more
core   +1 more source

Frequency‐Dependent Acoustic Reflection Coefficients of Flat Ground Assessed Using the Sonic Boom From the OSIRIS‐Rex Sample Return Capsule Recorded on Free Flying Balloons

Geophysical Research Letters, Volume 53, Issue 12, 28 June 2026.
Abstract Low frequency sound can travel great distances in planetary atmospheres. When these waves reflect off the air/ground interface, energy may be absorbed or transferred to mechanical waves in the subsurface. This study describes the direct and reflected acoustic wave generated by the re‐entry of the OSIRIS‐REx Sample Return Capsule captured on a ...
Daniel C. Bowman, Jonathan M. Lees, Siddharth Krishnamoorthy, Elizabeth A. Silber, Jacob S. Izraelevitz, Ashish Goel, Emalee Hough, Zach Yap, Mirza Samnani, Michael J. Fleigle, Justin R. LaPierre, James A. Cutts, Attila Komjathy   +12 more
wiley   +1 more source

Impact and Crystallization Modeling of the Sudbury Basin and Its Implications for a Hadean Crust

Journal of Geophysical Research: Planets, Volume 131, Issue 6, June 2026.
Abstract The 1.85 Ga Sudbury Structure hosts Earth's largest and best‐preserved impact‐induced melt sheet, the Sudbury Igneous Complex (SIC), which crystallized into distinct noritic, gabbroic, and granophyric layers. We conduct impact simulations with iSALE‐2D and crystallization modeling using alphaMELTS 2 to track the formation and evolution of the ...
Nicolas B. Litza, Miki Nakajima, J. Brian Balta, Steven B. Shirey, Dustin Trail, Kim A. Cone, Ian Szumila, Rasmus Haugaard, Taus R. C. Jørgensen, Scott D. Hull, Michael R. Ackerson   +10 more
wiley   +1 more source

Passage of Bolides Through the Atmosphere [PDF]

, 2011
Different fragmentation models are applied to a number of events, including the entry of TC3 2008 asteroid in order to reproduce existing observational data. Keywords meteoroid entry fragmentation modeling 1 Introduction Fragmentation is a very important
Popova, O.
core   +1 more source

Orbit, emission spectrum, and photometric analysis of two flickering sporadic fireballs [PDF]

, 2013
We present the observations of two fireballs that exhibit fast and quasi-periodic brightness variations along their atmospheric path. This phenomenon, which is known as “flickering”, is associated to the entry of spinning non ...
J. M. Trigo-Rodríguez, J. Alonso-Azcárate, J. M. Madiedo, N. Konovalova, A. J. Castro-Tirado, J. L. Ortiz, J. Lacruz, J. Cabrera-Caño   +7 more
core   +1 more source

Bolide Infrasound Signal Morphology and Yield Estimates: A Case Study of Two Events Detected by a Dense Acoustic Sensor Network

The Astronomical Journal
Two bolides (2016 June 2 and 2019 April 4) were detected at multiple regional infrasound stations, with many of the locations receiving multiple detections.
Trevor C. Wilson, Elizabeth A. Silber, Thomas A. Colston, Brian R. Elbing, Thom R. Edwards   +4 more
doaj   +1 more source

Microbial endolithic community at Meteor Crater

Meteoritics &Planetary Science, Volume 61, Issue 6, Page 955-962, June 2026.
Abstract Postimpact recovery and evolution in response to climate changes produced a modern ecosystem at Meteor Crater dominated by a grassland and woodland of piñon and juniper, which has been used to evaluate floral and megafaunal consequences of impact cratering during the Phanerozoic Eon of complex life.
David A. Kring, Charles S. Cockell
wiley   +1 more source