Observations from NASA's Wide-Field Infrared Survey Explorer (WISE) mission suggest that the family of asteroids commonly blamed for the extinction of the dinosaurs is not the culprit.
While scientists still believe that a large asteroid crashed into the Earth approximately 65 million years ago, they have ruled out the Baptistina asteroid remnant as the reason why dinosaurs disappeared from the face of the earth.
Based on findings from ground-based telescopes in a 2007 study, the remnant of a huge asteroid known as Baptistina was a possible suspect.
The theory states that Baptistina crashed into another asteroid in the main belt between Mars and Jupiter about 160 million years ago. This collision supposedly sent shattered pieces of asteroids as big as mountains, one of which was believed to have hit Earth and caused the dinosaur extinction, according to a NASA release.
But observations made by WISE using infrared light from January 2010 to February 2011 ruled out the so-called Baptistina family of asteroids as a culprit.
As a result of the WISE science team's investigation, the demise of the dinosaurs remains in the cold case files, NASA's Near Earth Object (NEO) Observation Program executive Lindley Johnson said. With infrared light, WISE was able to get a more accurate estimate, which throws the timing of the Baptistina theory into question.
The scientists credit advanced technology for the ability to reach this conclusion. WISE's predecessor was the Infrared Astronomical Satellite. WISE is hundreds of times greater in terms of sensitivity.
The team measured the size and reflectivity of the asteroid family members, which helped indicate how much time would have been required to reach their current locations. Calculations showed that the Baptistina parent asteroid only broke up around 80 million years ago that means 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. This process is thought to normally take many tens of millions of years, said study co-author Amy Mainzer at NASA's Jet Propulsion Laboratory in California in the release.
The asteroid family that produced the killer rock remains at large. Scientists are reconstructing positioning data in search of an asteroid about 6.2 miles (10 kilometers) in diameter that smashed into Earth, leaving a massive crater-shaped impact basin in the Gulf of Mexico and meteorite-type minerals in the fossil records, Discovery News reported.
We are working on creating an asteroid family tree of sorts, lead author Joseph Masiero said in a NASA statement. We are starting to refine our picture of how the asteroids in the main belt smashed together and mixed up.