Rock, Rattle and Roll
Planetary scientists seek to fill in gaps in outer solar system’s formative years
By Nadia Drake
Most scientists don’t wear protective headgear while giving talks. Then again, most scientists aren’t the target of pastry-wielding colleagues.
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But last October, when astronomer Hal Levison presented what he called a “slightly radical” mechanism for building the solar system’s giant planets, he was ready.
“I’m really a little intimidated about the reaction to this,” Levison said, reaching behind the podium and retrieving a baseball catcher’s mask, which he donned during his presentation, at a planetary science meeting in France.