How Enceladus got its water-spewing tiger stripes
https://www.sciencemag.org/news/2019/11/how-enceladus-got-its-water-spewing-tiger-stripes
Source: By Adam Mann, Science Magazine.
Excerpt: Researchers say they have solved a long-standing mystery about Saturn’s tiny, frozen moon Enceladus: why its south pole features long, water-spewing geysers known as tiger stripes. The study could also help explain why these unique formations aren’t seen on any other satellite in the solar system. Enceladus became a star attraction in 2005, when NASA’s Cassini mission photographed enormous jets of water ice and vapor emanating from four parallel slashes near its south pole. Since then, researchers have detected organic molecules and hydrogen in the jets—potential food for microbes—making Enceladus one of the top destinations in the search for life elsewhere in the Solar System. ...As it orbits around Saturn, Enceladus experiences gravitational tidal forces that squeeze and heat it. ...According to the new study, led by Douglas Hemingway of the Carnegie Institution for Science in Washington, D.C., as the moon cooled over time and some of the ocean water refroze, the new ice generated strain that built up in the surface until it broke. “It’s like your pipes freezing on a cold day,” says Nimmo, who was not involved in the study. ...That first fissure, extending down to the ocean, allowed a geyser to spray snow on its two flanks. The weight of this extra material produced more strains. ...Enceladus is the sole known possessor of tiger stripes (although controversial evidence suggests Jupiter’s moon Europa sports similar watery spouts). Its small size might explain why. The moon’s low gravity means that fractures can bust all the way through its outer shell and persist. On a more massive moon, the researchers say in their study, the weight of heavier ice would tend to squeeze cracks shut.... See also The New York Times article, How an Icy Moon of Saturn Got Its Stripes [https://www.nytimes.com/2019/12/09/science/enceladus-stripes-moon.html]
Source: By Adam Mann, Science Magazine.
Excerpt: Researchers say they have solved a long-standing mystery about Saturn’s tiny, frozen moon Enceladus: why its south pole features long, water-spewing geysers known as tiger stripes. The study could also help explain why these unique formations aren’t seen on any other satellite in the solar system. Enceladus became a star attraction in 2005, when NASA’s Cassini mission photographed enormous jets of water ice and vapor emanating from four parallel slashes near its south pole. Since then, researchers have detected organic molecules and hydrogen in the jets—potential food for microbes—making Enceladus one of the top destinations in the search for life elsewhere in the Solar System. ...As it orbits around Saturn, Enceladus experiences gravitational tidal forces that squeeze and heat it. ...According to the new study, led by Douglas Hemingway of the Carnegie Institution for Science in Washington, D.C., as the moon cooled over time and some of the ocean water refroze, the new ice generated strain that built up in the surface until it broke. “It’s like your pipes freezing on a cold day,” says Nimmo, who was not involved in the study. ...That first fissure, extending down to the ocean, allowed a geyser to spray snow on its two flanks. The weight of this extra material produced more strains. ...Enceladus is the sole known possessor of tiger stripes (although controversial evidence suggests Jupiter’s moon Europa sports similar watery spouts). Its small size might explain why. The moon’s low gravity means that fractures can bust all the way through its outer shell and persist. On a more massive moon, the researchers say in their study, the weight of heavier ice would tend to squeeze cracks shut.... See also The New York Times article, How an Icy Moon of Saturn Got Its Stripes [https://www.nytimes.com/2019/12/09/science/enceladus-stripes-moon.html]