The origin of the asteroid that killed the dinosaurs 65 million years ago, remains a mystery, a new study.
Some researchers believed that the asteroid was a killer piece of a large asteroid called Baptistina. Baptistina disintegrated after a massive collision in the space of about 160 million years, the theory went, spawning a swarm of mountain-sized chunks of rock. One of them, which eventually slammed into Earth, killing the dinosaurs and many other species.
Some researchers believed that the asteroid was a killer piece of a large asteroid called Baptistina. Baptistina disintegrated after a massive collision in the space of about 160 million years, the theory went, spawning a swarm of mountain-sized chunks of rock. One of them, which eventually slammed into Earth, killing the dinosaurs and many other species.
Scientists are convinced that a 6-mile wide (10 km asteroid) is what really wiped out the dinosaurs. But new observations from NASA Wide Field Infrared Space Telescope Survey Explorer (WISE) suggest space rock does not come from Baptistina.
The timing is not true, according to new study.
"Exhaustive research WISE science team, the disappearance of the dinosaurs left in Cold Case Files," said Lindley Johnson, program director for the purpose of the Earth Observation Program, near the NASA headquarters in Washington, said in a statement. [Photos: Deep Space Asteroids in]
Questioning the theory
Baptistina the first time by suspicions in the minds of some astronomers, according to a 2007 survey. In this study, researchers used data from visible-light telescopes on the ground in order to estimate the size and the reflection of Baptistina "family" - pieces of broken rock space outside.
These estimates contrast, the researchers decided that a large space rock probably broke about 160 million years ago. He would have given a lot of time to drift into a Baptist family of orbits of asteroids and other potentially dangerous for the dino-killing impact.
Since that study, however, different researchers have collected more information that casts doubt on the asteroid Baptistina as suspects. And the new study may finally exclude the entire family, the researchers said.
Looking Infrared
WISE interviewed on two occasions the entire sky in infrared light from January 2010 to February 2011. The telescope cataloged more than 157,000 asteroids in the main belt between Mars and Jupiter instance and found more than 33,000 space rocks.
WISE also measured the size and reflectivity of 1056 Baptistina family members. And these measures are more accurate than previous efforts, which in turn more accurate estimates of the age of the family of asteroids, the researchers said.
The new findings suggest that the Baptist broke up just 80 million years ago, not 160 million years ago, some scientists had thought.
"This does not provide collision remains a very long time to move the position of resonance, and fell to the ground for 65 million years ago," said study co-author Amy Mainzer, NASA Jet Propulsion Laboratory (JPL) in Pasadena , Calif. "This process is generally thought to be several tens of millions of years."
Spots are areas of resonance in the main asteroid belt, where gravitational push of Jupiter and Saturn can launch the asteroid belt and on a collision course with Earth. [Our Solar System: A Photo Tour of the planets]
Although the WISE wrapped his life in February 2011, researchers continue to use their observations to the map of the solar system, space rocks. They want to better deal with what became the asteroids - and wherever they are heading.
"We are working on creating a family tree of all types of asteroids," said study lead author, Joseph Masiero at JPL. "We're starting to refine our picture of how the asteroid main belt grinding and mixing together."
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