planet more likely to revolve around heavy metal star

Last year, it seemed as if the entire planet revolved around Ozzy Osbourne, and now there’s a scientific explanation (if the Oz were a gargantuan exploding ball of hydrogen, that is). Stars rich in iron, nickel, and other metallic elements are more likely to have planets, reported Debra Fischer of the University of California at Berkeley and her colleagues at the International Astronomical Union meeting in Sydney last week. The astronomers compared 754 stars, some with planets, most without, and proved a correlation between the amount of metal in a star and whether or not it formed planets. More metal means more raw material to build planets. “These results tell us why some of the stars in our Milky Way galaxy have planets while others do not. The heavy metals must clump together to form rocks, which themselves clump into the solid cores of planets,” said Geoffrey Marcy, a professor of astronomy at UC Berkeley. Added Fischer, “If you look at the metal-rich stars, 20 percent have planets. That’s stunning.”

This news brief appeared in the Random Data column of the Boston Globe’s Health/Science section on 7/29/2003.