The NASA Wide-field Infrared Survey Explorer (WISE) has shown that although it is still an asteroid that brought about the demise of the dinosaurs, it is not the one previously believed to be responsible.
The WISE spacecraft, built by Ball Aerospace & Technologies Corp. in Boulder, houses the science instrument that was built by the Space Dynamics Laboratory in Logan, Utah.
It was previously thought that an asteroid of the Baptistina family, in the asteroid belt between Mars and Jupiter, was the one that delivered the fatal impact to the dinosaurs.
Baptistina was an asteroid that impacted another asteroid in the main belt and broke up into mountain-size pieces and, with new observations from WISE’s infrared viewing, this family of asteroids can be ruled out for causing the crater in the Gulf of Mexico, the believed site of the infamous asteroid impact.
In a press release, Lindley Johnson, the program executive for the Near Earth Object (NEO) Observation Program Headquarters in Washington, stated, “As a result of the WISE science team’s investigation, the demise of the dinosaurs remains in the cold case files. 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. With infrared light, WISE was able to get a more accurate estimate, which throws the timing of the Baptistina theory into question.”
NEOWISE is the asteroid investigative part of the WISE mission and has catagorized over 157,000 asteroids, as well as finding 33,000 new ones.
The determination that a member of the Baptistina asteroid family is not responsible for the dinosaurs extinction comes down to a matter of timing. By using the infrared viewing capabilities of WISE, better knowledge of an asteroid’s size can be had. Infrared light from an asteroid is related to its temperature and size.
It has been determined that the original Baptistina asteroid broke up in half the time origianly thought.
Size and reflectivity of an asteroid gives information on travel time. The Baptistina piece would have had to have arrived to Earth in 15 million years.
Amy Mainzer, study co-author and the principal investigator of NEOWISE at NASA’s Jet Propulsion Laboratory (JPL) in Pasendena, California, said in a press release, “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.”
Caltech in Pasedena California manages JPL for NASA and JPL is manager and operator of WISE for the NASA Science Mission Directorate. The principal investigator of the project is Edward Wright of UCLA. Operations and the processing of data is performed at the Infrared Processing and Analysis Center at Caltech.
More reading on the WISE mission is at http://www.nasa.gov/wise
attributions: NASA press release