SSS 2009-01-06

（单词翻译）

This is Scientific American's 60-Second Science. I'm Cynthia Graber. This will just take a minute. 

If we want to learn more about our planet and other planets in the universe, we can get some help from stars that are long dead and gone. That’s what U.C.L.A.’s Michael Jura said at the American Astronomical¹ Society meeting January 5th. His team used observations from NASA’s Spitzer Space Telescope to investigate dead white dwarf² stars.

Dust and debris³ swirl⁴ around young stars. The pieces clump⁵ together to form asteroids⁷ and bigger planets. When a star like our sun finally dies, it blows itself up, bright red. Then it shrinks down into a skeleton of its former self—a white dwarf. The gravitational pull of these white dwarfs⁸ can attract nearby asteroids that then get pulverized⁹.

Eight different white dwarf systems were examined. In the surrounding asteroid⁶ dust, there was a mineral similar to olivine, which is common here on Earth. And there wasn’t much carbon, also similar to the make-up of asteroids and rocky planets in our own solar system. The results suggest that the same materials that make up Earth and our solar system's other rocky bodies could be common in the universe. As could be rocky planets themselves. An insight for which we can thank dead stars.

Thanks for the minute for Scientific American's 60-Second Science. I'm Cynthia Graber.