This really sounds like something a 4th grader made up. "A planet that is 1/3 solid diamond!" But no! Astronomers think they have discovered a planet that is made mostly of diamonds just about 40 light years from here. It seem far fetched, but there it is... Its about twice the size of the Earth and it swings around its star (a year for it) in only 18 hours. The year is so short there because it is very close to the star. That also means that the temperature is very warm. They estimate temperatures around 3900 degrees Fahrenheit.
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