Gizmorama - June 23, 2014

Good Morning,

Do you know what bridgmanite is? Well, it's the new name for Earth's most abundant mineral. And now we've actually see it!

Learn about this interesting story and more from the scientific community in today's issue.

Until Next Time,
Erin

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*-- Scientists see Earth's most abundant mineral for the first time --*
QUEENSLAND, Australia (UPI) - It's hard to be ubiquitous and well-concealed, but that's what silicate-perovskite has been for some time -- until now.

Having recently been seen by scientists for the first time, silicate-perovskite -- the world's most abundant mineral, previously named for its chemical components and crystal structure -- has been rechristened as bridgmanite.

The magnesium-silicate mineral is abundant, but has remained concealed because it's buried deep below Earth's surface, in its mantle. Scientists, however, finally got a glimpse of the mineral -- sandwiched between other rock layers in the middle of a 4.5-billion-year-old meteorite that crashed into Australia in 1879.

"It is a very exciting discovery," said Chi Ma of Caltech, who along with Oliver Tschauner, of the University of Nevada, Las Vegas, identified and named the mineral.

"We finally tracked down natural silicate-perovskite (now bridgmanite) in a meteorite after a five-year investigation, and got to name the most abundant mineral on Earth. How cool is that?"

Ma and Tschauner were first clued into the mineral's presence when they used x-ray diffraction mapping to gain a general understanding of the meteorite's makeup. They were able to zoom in on the silicate-perovskite with a high-resolution scanning electron microscope.

The mineral's new name is an homage to physicist Percy Bridgman, a physicist awarded the 1946 Nobel Prize in Physics for his work in the field of high-pressure physics. The silicate mineral with a perovskite structure is impressive for its ability to remain stable under the high pressure and hot temperature of deep Earth.

"Our finding of natural bridgmanite not only provides new information on shock conditions and impact processes on small bodies in the solar system," explained Ma, "but the tiny bridgmanite found in a meteorite could also help investigations of phase transformation mechanisms in the deep Earth."

The mineral's identification and renaming was approved earlier this month by the International Mineralogical Association's Commission on New Minerals, Nomenclature and Classification.


*-- Scientists explain why some turtles breathe through their rear ends --*
WASHINGTON (UPI) - Apparently, some turtle species breathe out of their butts. Talk about bad breath.

Until recently, however, scientists didn't really know why some turtles -- most notably Australian Fitzroy river turtle and the North American eastern painted turtle -- took in air through the back end. Chalk it up to another one of nature's cruel but hilarious jokes.

But now, scientists have an explanation. As always, the answer is evolutionary problem solving.

The turtles in question hibernate for an extended part of the winter in frigid waters, sometimes for as long as five months. That requires a lot of breathing underwater. Unfortunately, a turtle's shell -- the product of ribs and vertebrae that slowly flattened out and fused together over time -- is built for protection, not to support the muscle system that enables the robust pulmonary setup gifted to so many mammals.

A turtle's muscles are built to help it emerge from the gaps in its shell, not to contract and expand lungs, inhaling and exhaling oxygen. Thus, breathing in and out in the normal fashion requires a lot of work for the turtle -- muscle exertion that causes a buildup of acid. And too much acid in the body is a bad thing.

Luckily, the turtle's cloaca -- the rear end hole (not an anus) that allows the reptile to excrete, urinate, and lay its eggs -- features two sacs, or bursa, which more efficiently absorb oxygen. Though the Australian Fitzroy river turtle, North American eastern painted turtle, and other rear-breathing turtles can breathe through their mouths if they feel so inclined, the bursa help them take in oxygen without expending as much energy and producing as much acid byproduct.

In related news, other turtles pee through their mouths.

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