Erratum
The first sentence of the second paragraph of Richard A. Kerr's Research News article "Halocarbons linked to ozone hole" (5 June, p. 1182) should have read, "Using a technique borrowed from galactic astronomy, the Stony Brook researchers believe that they have detected roughly 0.5 to 1.5 parts per billion of chlorine monoxide within the deepening hole. ..." The article incorrectly referred to "0.5 to 1.5 parts per million."