Icy Saturn moon, a possible victim of cosmic hit-and-run
Enceladus, a large glacial and oceanic moon of Saturn, may have stolen a blow out of this world.
While combining the data collected by the Cassini mission for NASA during Enceladus flights, astronomers at Cornell University, the University of Texas and NASA have found the first evidence that the axis of the moon is redirected .
By examining the geology of the moon, the group showed how Enceladus appears to have been removed from its original axis of about 55 degrees.
“We have found a chain of low-lying areas or basins that trace a belt across the surface of the moon, which we believe fossil remains from the past and the former equator and poles,” said lead author Radwan Tajeddine. “Their model reflects spatial variations in the ice sheet, in line with a variety of geological features visible in Cassini images.”
At the current southern end of the moon, active jets discharge water vapor (as well as organic compounds, gases, salts, and silica) through the deep ocean ventilation holes beneath the surface of the ice moon crest. It is a place technically known as the ground name of the south pole, and astronomers have christened the long geologically active “Tiger Stripes” fractures – each about 80 miles long and a little over a mile wide.
Tajeddine believes that an asteroid could strike the region of the south pole of the current of the Moon when it was closer to the equator in the past. “It is unlikely that geological activity in this field was initiated by the internal process,” he said. “We believe leading to such a reorientation of the moon, it is possible that an impact is behind the formation of abnormal earth.”
Stumbled, reptiles and unstable after a sudden asteroid the physical rotation Enceladus finally restored stability, a process that probably took more than a million years. For this, the north-south axis was to change: a mechanism called “true polar displacement”.
The topographical and geological characteristics of Enceladus are explained by geophysicists, but the north and south poles of the moon are very different. The south is active and geologically young, while the north is cratered and looks much older.