Which Rock Killed The Dinosaurs? The Plot Thickens
I've always loved dinosaurs, but what guy didn't grow up like that? I even took a class at UMD called 'The Life And Death Of Dinosaurs'. At the time taking that class also meant I never had to take another science class, like the ones with labs (they since have closed that loophole). It's pretty much accepted that a asteroid was a primary culprit in their demise, but from where?
A 65-million-year-old murder mystery just got a bit more mysterious.
Which "family" of asteroids killed earth's dinosaurs?
New data from NASA's orbiting Wide-field Infrared Survey Explorer (WISE) throws doubt on a 2007 theory that blamed the death of the dinosaurs on fragments from an asteroid family called Baptistina, located between Mars and Jupiter.
Baptistina was a huge asteroid which crashed into another space rock millions of years ago, sending mountain-sized pieces flying in various directions.
Scientists had theorized one of those Baptistina fragments slammed into the Gulf of Mexico, triggering the end of Earth's reptile dynasty.
The earlier Baptistina estimates were off, says Lindley Johnson, program executive for the Near Earth Object (NEO) Observation Program at NASA Headquarters in Washington. "With infrared light, WISE was able to get a more accurate estimate."
Infrared light is electromagnetic radiation which humans sense as heat.
Reconstructing what really happened so many millions of years ago sounds very much like a script from a detective show.
Baptistina broke up into chunks about 15 million years before the dino-killing event, according to WISE data - which doesn't fit scientists' timeline.
In this crime of epoch proportions, that gives Baptistina a pretty good alibi.
Baptistina asteroids apparently were nowhere near the scene of the crime because it likely would have taken millions of years longer for them to drift into regions of space called resonances.
Resonances have gravitational forces created by Saturn and Jupiter which can shoot asteroids toward Earth - sort of like a pinball machine.
"It doesn’t completely rule it out as the source of the dino-killing culprit," says Amy Mainzer, who co-authored the WISE study. "But it does give theorists something new to think about."