Dinosaur mystery: The asteroid didn’t do it scientists now say
Published 20/09/2011 | 09:22
THE ASTEROID believed to have wiped out the dinosaurs 65 million years ago may be innocent.
While NASA scientists still believe a large meteor crashed into the Earth, leading to the extinction of the dinosaurs, the widely-held Baptistina theory now appears to have been all but ruled out.
The Chicxulub crater was discovered in 1978 off the Yucatan Peninsula in Mexico and was thought to be ground-zero for the Baptistina asteroid that wiped out the dinosaurs.
However scientists have revised that theory after new research by NASA's Wide-field Infrared Survey Explorer (WISE) seems to have ruled that theory out.
"As a result of the WISE science team's investigation, the demise of the dinosaur’s remains in the cold case files," said NASA scientist Lindley Johnson.
"The original calculations with visible light estimated the size and reflectivity of the Baptistina family members, leading to estimates of their age, but we now know those estimates were off.”
WISE, a program that uses infrared to determine the age of things in space produced results that created new questions around the timing of the Baptistina event.
Scientists established that the Baptistina asteroid actually broke up closer to 80 million years ago, half as long as the 160 million years originally proposed, meaning the remnants had only 15 million years to get flung down to Earth to cause the extinction of the dinosaurs.
"This doesn't give the remnants from the collision very much time to move into a resonance spot, and get flung down to Earth 65 million years ago," said NASA scientist Amy Mainzer. "This process is thought to normally take many tens of millions of years."
Scientists hope to come up with a new suspect for the mass-extinction of the dinosaurs as a result of the new evidence discovered.