COVER The destruction of comet C/1999 S4 (LINEAR). Images from the Hubble Space Telescope on 6 to 8 July (right, top to bottom) show an outburst that culminated in the ejection from the nucleus (within the white area) of a small fragment (smaller white area, bottom). On or about 22 July, the comet nucleus broke into at least 16 large fragments and debris. Images from the Lowell Observatory on 26 and 28 July and from the Perth Observatory on 2 August (left, top to bottom) show the dust from this event spreading out to form a tail. 1326 [Images: T. L. Farnham et al., H. A. Weaver et al., NASA]
