September 23rd, 2011 17:14 EST
Were Asteroids the Culprit Behind the Extinction of Dinosaurs? Or was it Something Else?
There are many myths as to why the dinosaurs that once ruled this planet suddenly became extinct. I have heard it was because of a giant asteroid or a bunch of asteroids slammed into the earth millions of years ago and I have heard other reasons as to why dinosaurs became extinct.
NASA is now conducting some behind the scenes research from their Wide-field Infrared Survey Explorer (WISE) mission to see if the sea of asteroids or the one giant asteroid that supposedly blanketed and slammed into the earth during the dinosaur era were really why dinosaurs disappeared.
Scientists are still baffled by this but also at the same time are just about sure that it was asteroids or one giant asteroid that killed off the dinosaurs and other life forms but need to have more evidence to prove this theory. The question is if it was one large asteroid that hit the earth and took out the dinosaurs where exactly did this one large asteroid come from?
The theory about this at the present time is that a huge asteroid named Baptistina crashed into another large asteroid somewhere around 160 million years ago and somewhere between Mars and Jupiter which is the main asteroid belt, the two asteroids colliding with one another sent shattered pieces of the asteroid named Baptistina the size of mountains crashing into earth.
This scenario and theory was from a 2007 study using visible light data from ground based telescopes but since the 2007 study this possible theory has taken a back seat and is believed this was not the case and this theory is not why the dinosaurs became extinct.
The shattered pieces of the little asteroids from the large asteroid Baptistina are still floating around in the main belt like white, snowy cotton ball clouds on a warm and breezy spring day. So, Scientist were able to study those asteroid remnants from Baptistina coming up short on the first theory.
Lindley Johnson who is the program executive for the Near Earth Object (NEO) Observation Program at NASA Headquarters in Washington commented by stating, . "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." (Johnson, 2011) So, with this statement the WISE mission continued and went into phase two of the dinosaur extinction mystery.
The next phase of the mission was to study the celestial sky using infrared light. From January 2010 through February 2011, the WISE telescope did exactly this even using the asteroid hunting portion of the mission called NEOWISE and from this was able to collect data from 157,000 asteroids in the main belt and discovered 33,000 new ones exist.
What scientists were researching for and trying to find out is how long each asteroid took to reach their current location including the remnant asteroids from the Baptistina family. So, what scientists do is detect the infrared light coming from each asteroid which the amount of infrared light coming from anyone of the asteroids is according to the body temperature and size of that asteroid. This gives scientists the size of the asteroid which then the objects reflectivity can be re-calculated by combining infrared with visible-light data.
The project NEOWISE team measured and took data from about 120,000 asteroids in the main belt include about 1,056 asteroids still floating around there from the Baptistina family. From this data, scientists were able to calculate that the first or huge Baptistina asteroid that was thought to have been the culprit behind the extinction of the dinosaurs actually broke apart 80 million years ago not 160 million years ago when the dinosaurs became extinct. So, the first theory of the large Baptistina asteroid colliding with another asteroid and breaking up into large mountain size chunks which supposedly killed off the dinosaurs is not confirmed. Writing this, I almost feel like a detective trying to solve a crime. So, the Baptistina asteroid is innocent and free to go.
So, with the collected data from the NEOWISE research and the asteroids surveyed the second part of this answer is that larger asteroids would not disperse in their orbits as fast as smaller ones. The results revealed a chunk of the original Baptistina asteroid needed to hit Earth in less time than previously believed, in just about 15 million years, to cause the extinction of the dinosaurs. (nasa.com)
Amy Mainzer who is the principle investigator of the NEOWISE project commented by stating, "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." Resonances are areas in the main belt where gravity nudges from Jupiter and Saturn can act like a pinball machine to fling asteroids out of the main belt and into the region near Earth. " (Mainzer, 2011)
NASA continues to come up with innovative ways to research and study asteroids and if the asteroids played a part in the extinction of dinosaurs. There are still bits and pieces of evidence that asteroids may still have been the culprit including a huge crater-shaped image that sits in the Gulf of Mexico with fossilized rare minerals in it that could have very well was an asteroid hit 65 million years ago along with other various types of evidence around this planet of possible asteroid hits. It`s like a huge puzzle except the pieces of it are not sitting in front of you ready to assemble, scientists are having to go out and find the pieces to the extinction of the dinosaurs puzzle and see if each piece they find fits into the complete theory of how the dinosaurs really died off and if the asteroids were the cause. The asteroids that are still floating around and have been for millions of years in the main asteroid belt are being looked at by scientists for their reflective properties and their trace of family history.
Joseph Masiero who is the main author of the study had this to say, "We are working on creating an asteroid family tree of sorts. We are starting to refine our picture of how the asteroids in the main belt smashed together and mixed up."(Masiero, 2011)
So, what really caused the extinction of the dinosaurs? That is the question and the question still remains a mystery to scientists today. So, if it was not asteroids, what killed off the large lizards that once roamed this earth freely and owned it like it was a football team playing the championship game on their home turf in their house?
Mainzer, A., Masiero, J., (2011) NASA`S WISE RAISES DOUBT ABOUT ASTEROID FAMILY BELIEVED RESPONSIBLE FOR DINOSAUR EXTINCTION, (www.nasa.com) Retrieved 2011.