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Practice Reading: Reading and Writing Fill in the Blanks
ID: #51255
Twinkle
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When it comes to sheer celestial bling, stars might not corner the market on twinkle. Because beneath their rocky , some terrestrial planets may be half diamond. So said at the fall meeting of the American Geophysical Union. The were fixing to study how diamonds form here on Earth, under the conditions found in the planet's lower mantle. So they took a tiny sample of iron, carbon, and oxygen, abundant in Earth's , and cooked it up at about 3,800 degrees Fahrenheit and 9.5 million pounds of pressure per square inch. What they saw was that iron hooks up with oxygen to produce rust, and leaves behind pockets of carbon, which become diamond. Now, what happens if they look not at Earth but at a planet in a solar system where there's even more carbon? According to the model, the carbon merges with iron to form a core made of steel, leaving a carbon mantle rich with diamond. Whether the Milky Way harbors such gems is still an open question. One thing is for sure: they probably wouldn't harbor life. Because diamonds readily transfer heat. So a planet made of diamond would be one cold stone.
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