Interacting Atmospheric Plumes from Bolide Swarms
Abstract
We have used the Sandia shock physics code, CTH, to simulate the interaction of atmospheric impact plumes generated by an array of simultaneous impact events on Earth. This work was stimulated by advances in the understanding of atmospheric impact processes since the impact of comet Shoemaker-Levy 9 (SL9), and by our desire to apply what we have learned to terrestrial processes. We performed 2-D axisymmetric calculations with pseudoperiodic boundary conditions to determine the effects of the interaction of plumes resulting from a cluster of impacts, compared to a single, isolated event. We simulated a plume from the impact of a 20 km/s, 34 meter-diameter asteroid (kinetic energy of 3 megatons) at vertical incidence, and compared its evolution and collapse to interacting plumes from arrays of impacts with near-neighbor separation distances of 40, 100, and 200 km. As expected, the closer-packed arrays lead to denser plumes that reach higher altitudes and generate higher temperatures within denser air upon collapse. These results can be applied to models for generation of layered tektites by radiative heating from an impact-heated atmosphere. Simulations of interacting plumes from bolide swarms can also be used to consider dispersed rubble-pile models for SL9.
- Publication:
-
Lunar and Planetary Science Conference
- Pub Date:
- March 1996
- Bibcode:
- 1996LPI....27..135B
- Keywords:
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- BOLIDES;
- PLUMES: IMPACT;
- SHOEMAKER-LEVY 9;
- TEKTITES: LAYERED