The Last Extinction and Science learning with NOVA

My son and I really enjoy watching NOVA specials on our home DVR. We haven’t done this in awhile, but last week we made some time to watch the episode titled, “The Last Extinction.” For some reason our DVR cut the episode off early, so we were delighted to find that the entire program is available online to watch for free! We were able to watch the rest of Chapter 5, “Where’s the Crater,” as well as the final chapter, “An Open Question,” by connecting a MacBook laptop to our home TV and stereo amplifier.

There were LOTS of new vocabulary words and concepts we learned about for the first time as a result of this program. I had never heard of nano-diamonds or hexagonal diamonds, which the program authors explained must be “completely extra-terrestrial” because of their unique atomic, crystalline structures. See the Washington Post article, “Gems Point to Comet as Answer to Ancient Riddle,” from January 2, 2009, for more on this.

Scientists have been looking for Iridium traces in the “black mat” layer of geologic history, preserved well in parts of Arizona, which appears to be a smoking gun showing when a large number of enormous, North American mammals were suddenly killed off. “The Last Extinction” theory is that instead of “overkill theory” which holds that native people were the cause of these extinctions, a massive asteroid collision similar to the one theorized to have caused the extinction of the dinosaurs was responsible for the North American large mammal extinction that took place only about 12,900 years ago. This extinction involved around 35 different, large North American mammals.

One of the biggest questions posed by scientists who doubt this theory is, “Where is the impact crater?” The NOVA program explains that the crater could be missing because the impact could have been distributed over parts of the northern ice sheets, and therefore have not left visible, residual evidence behind.

It’s amazing to consider that the Greenland ice sheet includes over 450,000 years of geologic history. Wow.

Imagine a “storm of comets” hitting the earth. That’s been the subject of multiple books and films, including the 1998 movie “Armageddon.” Last week I saw the movie “Knowing,” which deals with an extinction event caused by massive coronal flares rather than an asteroid collision. These events have happened in the past, and could happen in the future. It’s amazing to consider what might have caused these massive extinctions in North America such a short time ago, geologically speaking, and consider how we can best theorize their cause today given the evidence as well as the tools at our fingertips.

NOVA rocks. It’s amazing we have access to such thought provoking and inspiring scientific programs like these as part of our monthly cable TV subscription, and that (thanks to our DVR as well as the NOVA website) we can watch them in their entirety, at our leisure.

I think many of the conversations we’ve had at home following these NOVA specials have likely surpassed the potential for engagement provided by my son’s 5th grade science textbook and district approved science curriculum. It’s so much fun to learn like this together at home!

Technorati Tags:
nova, science, iridium, overkill, extinction, asteroid, armageddon, learning

If you enjoyed this post and found it useful, subscribe to Wes’ free newsletter. Check out Wes’ video tutorial library, “Playing with Media.” Information about more ways to learn with Dr. Wesley Fryer are available on wesfryer.com/after.

On this day..