But this disturbance is more mysterious than Darth Vader. UCLA scientists don't know exactly what it was, but they believe it occurred within the Solar System 65 million years ago. The ensuing pandemonium upset Solar System dynamics causing Mercury, Earth, and Mars to go off course.
"We speculate that it may also have perturbed asteroids in the inner part of the asteroid belt, throwing one or more of them into Earth-crossing orbits," explained Bruce Runnegar, Director of UCLA's Center for Astrobiology.
"Thus, the ultimate cause of the K-T impact--and demise of the dinosaurs--may have been a chaos-induced change in Solar System dynamics."
Runnegar will present the team's findings at the Earth Systems Processes conference on Wednesday, June 27, in Edinburgh, Scotland. The Geological Society of America and the Geological Society of London will co-convene the June 24-28 meeting.
The other team members, Ferenc Varadi, a UCLA geophysicist, and Michael Ghil, the Director of UCLA's Institute of Geophysics and Planetary Physics, have worked for years on chaos in the Solar System and, in particular, the role of in-step motions known as resonances in giving rise to the chaos.
This earlier work on resonances and chaos among the planets and the asteroids prepared the ground for the present tantalizing results.
"In order to better understand the history of the inner Solar System over hundreds of millions of years, we carried out several accurate, long-term, numerical simulations of the orbits of the nine major planets using physical models with increasing complexity," Runnegar said.
"Our best calculations show that the dynamical state of the inner Solar System changed abruptly about 65 million years ago." Ghil added: "It is possible that it was a transition through a special kind of resonance that produced the abrupt change at the K-T boundary."
While scientists generally accept that there was indeed an extraterrestrial impact 65 million years ago (at the Cretaceous/Tertiary or K-T boundary) that wiped out most living species on Earth, they do not agree on the nature of what caused that impact.
Was it an asteroid? Was it a comet? Now at least we have a better idea and a vital clue to what really happened with this Earth-shaking event so many millions of years ago.
Institute of Geophysics and Planetary Physics at UCLA
Geological Society of London
Geological Society of America
Subscribe To SpaceDaily Express
Mass Extinction At The Triassic-Jurassic Boundary
Edinburgh - June 27, 2001
Who did it? Who pulled the trigger, or rather, what pulled the trigger at the Triassic-Jurassic boundary that wiped out 20% of all marine families in Earth's oceans, and, on land, most non-dinosaurian archosaurs, most therapsids, and the last of the large amphibians? Whatever it was, it shot down much of the competition so dinosaurs could later dominate the Earth.
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2016 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.|