Constructive Interference of Seismic Surface Waves Antipodal to Crater Impact Sites on Terrestrial Bodies
ISEF · 2016 First Award
Overview
Asteroid impacts on planetoid bodies have been widely studied. A secondary effect that has been proposed due to these impacts is that the seismic waves should violently converge again at the antipodal point to the impact, 180 degrees away. There is geological evidence and computer modeling that support this converging wave theory, but it has never been directly observed in a laboratory experiment. The reason for this is that in rock, the compression waves propagate far too quickly (~3 km/sec) to be directly observable. The research described here solves this problem using a laboratory model by submerging a large (80 centimeter) balloon in water and striking it with a controlled impulse. Because the force modulus (surface tension of the latex membrane) is so small, and the inertial mass so large, the phase velocities of the surface waves are slowed down to the order of ~1 m/sec, and can therefore be visualized in detail. Gravity would ordinarily strongly distort a sphere with a tiny restoring force/mass ratio, but since the 270 kg water balloon effectively weighs nothing when submerged, gravitational deformation becomes a non-issue. Video taken at 240 frames per second of the resulting motion was then examined in slow motion. The slowed video very strikingly reveals the antipodal focusing effect. The observed wave motion was then compared with, and is in good agreement with, a theoretical one dimensional wave equation model. The video can be found here: https://youtu.be/bn6XMyTGWlY. It can also be searched for on YouTube as “Antipodal Focusing of Asteroid Impacts - First Visual Evidence.”
Awards (3)
- First Award of $5,000 $5,000
- Intel ISEF Best of Category Award of $5,000 $5,000
- European Organization for Nuclear Research-CERN: Second Award of $1,500 $1,500
Competition history
- ISEF 2016
Resources
Related projects
ISEF · 2020
Is the Crater Diameter Ruled by Gravity? Experimental Verification of Gravitational Scaling Law of Craters
CSEF · 2004
Simulation of Terrestrial Impact Craters
ISEF · 2020
The Effect of Meteor Impact Location on the Energy Transmitted
CSEF · 2002
Impact Craters: The Effects of Different Angles of Impact
CSEF · 2005
Analysis of a Potential Impact Crater in the Sacramento Basin
CSEF · 2007
When Waves Collide
ISEF · 2021
Crater Correlations: A Morphological Analysis on Lunar and Mercurian Simple Impact Craters
CSEF · 2015
Testing Meteorite Impact Distances on Triton
Closest projects by meaning, across every fair and year in the corpus.
Browse more like this
Source: Regeneron International Science and Engineering Fair