TY - JOUR A1 - Tiscareno, Matthew S. A1 - Mitchell, Colin J. A1 - Murray, Carl D. A1 - Di Nino, Daiana A1 - Hedman, Matthew M. A1 - Schmidt, Jürgen A1 - Burns, Joseph A. A1 - Cuzzi, Jeffrey N. A1 - Porco, Carolyn C. A1 - Beurle, Kevin A1 - Evans, Michael W. T1 - Observations of Ejecta clouds produced by impacts onto Saturn's rings JF - Science N2 - We report observations of dusty clouds in Saturn's rings, which we interpret as resulting from impacts onto the rings that occurred between 1 and 50 hours before the clouds were observed. The largest of these clouds was observed twice; its brightness and cant angle evolved in a manner consistent with this hypothesis. Several arguments suggest that these clouds cannot be due to the primary impact of one solid meteoroid onto the rings, but rather are due to the impact of a compact stream of Saturn-orbiting material derived from previous breakup of a meteoroid. The responsible interplanetary meteoroids were initially between 1 centimeter and several meters in size, and their influx rate is consistent with the sparse prior knowledge of smaller meteoroids in the outer solar system. Y1 - 2013 U6 - https://doi.org/10.1126/science.1233524 SN - 0036-8075 VL - 340 IS - 6131 SP - 460 EP - 464 PB - American Assoc. for the Advancement of Science CY - Washington ER - TY - JOUR A1 - Cuzzi, Jeff N. A1 - Burns, Joseph A. A1 - Charnoz, Sébastien A1 - Clark, Roger N. A1 - Colwell, Josh E. A1 - Dones, Luke A1 - Esposito, Larry W. A1 - Filacchione, Gianrico A1 - French, Richard G. A1 - Hedman, Matthew M. A1 - Kempf, Sascha A1 - Marouf, Essam A. A1 - Murray, Carl D. A1 - Nicholson, Phillip D. A1 - Porco, Carolyn C. A1 - Schmidt, Jürgen A1 - Showalter, Mark R. A1 - Spilker, Linda J. A1 - Spitale, Joseph N. A1 - Srama, Ralf A1 - Sremcević, Miodrag A1 - Tiscareno, Matthew Steven A1 - Weiss, John T1 - An evolving view of Saturn's dynamic rings N2 - We review our understanding of Saturn's rings after nearly 6 years of observations by the Cassini spacecraft. Saturn's rings are composed mostly of water ice but also contain an undetermined reddish contaminant. The rings exhibit a range of structure across many spatial scales; some of this involves the interplay of the fluid nature and the self-gravity of innumerable orbiting centimeter- to meter-sized particles, and the effects of several peripheral and embedded moonlets, but much remains unexplained. A few aspects of ring structure change on time scales as short as days. It remains unclear whether the vigorous evolutionary processes to which the rings are subject imply a much younger age than that of the solar system. Processes on view at Saturn have parallels in circumstellar disks. Y1 - 2010 UR - http://www.sciencemag.org/ U6 - https://doi.org/10.1126/science.1179118 SN - 0036-8075 ER -