Brain Food

Don Davis/NASA

Scientists are dismissing a popular theory about mass extinction since the last ice age. The Younger Dryas Impact Hypothesis contends an asteroid hit Earth 13,000 years ago changing the climate instantly and dramatically. Scott Anderson, a paleoecologist at Northern Arizona University, is part of an international research team that looked for evidence to support this explanation, but didn't find any.


Getty Images

Bach and Mozart have one. ZZ Top has one. And of course all of The Beatles have them. They are asteroids.


National Park Service

Auto exhaust at the Grand Canyon may be ruining more than just the view; it might be harming native plants, in particular. The National Park Service wants to know just how harmful excess nitrogen is to the ecosystem, so they offered a grant to soil ecologist Nancy Johnson at Northern Arizona University. Her study involved taking samples of soil, air and pinyon pine needles at the heavily trafficked South Rim. 


Northern Arizona University

Scientists are concerned that soil in the Southwest is drying out and blowing away from climate change. Flagstaff-based ecologist Matt Bowker believes the key to protecting it lies in the biocrust, or top layer. He calls it "Earth's living skin", and he's growing it in a lab at Northern Arizona University.


Colorado River Discovery

The first all-electric commercial passenger raft launched this summer on the Colorado River. Instead of running on a gas-powered motor, the Helios uses rechargeable lithium ion batteries. It took 10 years to engineer and is a partnership between the river rafting industry and the National Park Service. 


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