Subscribe free to our newsletters via your
. 24/7 Space News .




DEEP IMPACT
Did a "forgotten" meteor have a deadly, icy double-punch?
by Bob Beale
Sydney, Australia (SPX) Sep 26, 2012


File image.

When a huge meteor collided with Earth about 2.5 million years ago and fell into the southern Pacific Ocean it not only could have generated a massive tsunami but also may have plunged the world into the Ice Ages, a new study suggests.

A team of Australian researchers says that because the Eltanin meteor - which was up to two kilometres across - crashed into deep water, most scientists have not adequately considered either its potential for immediate catastrophic impacts on coastlines around the Pacific rim or its capacity to destabilise the entire planet's climate system.

"This is the only known deep-ocean impact event on the planet and it's largely been forgotten because there's no obvious giant crater to investigate, as there would have been if it had hit a landmass," says Professor James Goff, lead author of a forthcoming paper in the Journal of Quaternary Science. Goff is co-director of UNSW's Australia-Pacific Tsunami Research Centre and Natural Hazards Research Laboratory.

"But consider that we're talking about something the size of a small mountain crashing at very high speed into very deep ocean, between Chile and Antarctica. Unlike a land impact, where the energy of the collision is largely absorbed locally, this would have generated an incredible splash with waves literally hundreds of metres high near the impact site.

"Some modelling suggests that the ensuing mega-tsunami could have been unimaginably large - sweeping across vast areas of the Pacific and engulfing coastlines far inland. But it also would have ejected massive amounts of water vapour, sulphur and dust up into the stratosphere.

"The tsunami alone would have been devastating enough in the short term, but all that material shot so high into the atmosphere could have been enough to dim the sun and dramatically reduce surface temperatures. Earth was already in a gradual cooling phase, so this might have been enough to rapidly accelerate and accentuate the process and kick start the Ice Ages."

In the paper, Goff and colleagues from UNSW and the Australian Nuclear Science and Technology Organisation, note that geologists and climatologists have interpreted geological deposits in Chile, Antarctica, Australia, and elsewhere as evidence of climatic change, marking the start of the Quaternary period. An alternative interpretation is that some or all of these deposits may be the result of mega-tsunami inundation, the study suggests.

"There's no doubt the world was already cooling through the mid and late Pliocene," says co-author Professor Mike Archer. "What we're suggesting is that the Eltanin impact may have rammed this slow-moving change forward in an instant - hurtling the world into the cycle of glaciations that characterized the next 2.5 million years and triggered our own evolution as a species.

"As a 'cene' changer - that is, from the Pliocene to Pleistocene - Eltanin may have been overall as significant as the meteor that took out the non-flying dinosaurs 65 million years ago. We're urging our colleagues to carefully reconsider conventional interpretations of the sediments we're flagging and consider whether these could be instead the result of a mega-tsunami triggered by a meteor."

.


Related Links
UNSW
Asteroid and Comet Impact Danger To Earth - News and Science






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








DEEP IMPACT
Math says Earth safe from asteroid
Moscow (UPI) Aug 29, 2012
Russian scientists say recalculation of the path of a large asteroid named Apophis indicates a significantly low likelihood of a hazardous encounter with Earth. Researchers at the Institute of Astronomy of the Russian Academy of Sciences have re-run the numbers on the asteroid, thought to be the size of two football fields, institute research fellow Viktor Shor said Wednesday. Th ... read more


DEEP IMPACT
China has no timetable for manned moon landing

Senior scientist discusses China's lunar orbiter challenges

NASA sees 'gateway' for space missions

Protection for Moon, Mars astronauts eyed

DEEP IMPACT
Why Curiosity Matters

Robotic Arm Tools Get to Work

NASA Mars Rover Targets Unusual Rock Enroute to First Destination

Curiosity's Stars and Stripes

DEEP IMPACT
B612 Wins Funding Support From Prominent Business Leadersy

Cavenauts return to Earth

Brazil unveils tax incentives to boost tech innovation

New Technology Being Stymied by Copyright Law

DEEP IMPACT
China Spacesat gets 18-million-USD gov't support

Tiangong Orbit Change Signals Likely Date for Shenzhou 10

China Focus: Timeline for China's space research revealed

China eyes next lunar landing as US scales back

DEEP IMPACT
Crew Members Prepare for Departure

ISS Crew Lands Safely in Kazakhstan

ISS Crew Enjoys Light Duty Day

Europe's ATV-3 Spacecraft to Readjust Space Station's Orbit

DEEP IMPACT
California Governor Signs the Spaceflight Liability and Immunity Act

Processing is underway with the next Automated Transfer Vehicle to be orbited by Arianespace

Fueling underway with the Galileo satellites for next Soyuz launch from French Guiana

SpaceX, NASA Target Oct. 7 Launch For Resupply Mission To Space Station

DEEP IMPACT
Meteors Might Add Methane to Exoplanet Atmospheres

Two 'hot Jupiters' found in star cluster: NASA

Planets Can Form in the Galactic Center

Birth of a planet

DEEP IMPACT
Northrop Grumman Completes Field Installations of New B-2 Radar System

Setback for Lynas rare earths plant

Retailers to add radical 'focus later' camera

New California Law Boosts Sustainable Materials Industry




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal 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