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2013 Edition -- Target 2: Dione, Grade 5 and 6 Winner

2013 Essay Contest: Target 2, Grade 5 and 6

Anisha Kundu
Target 2, Dione
Anisha Kundu

Peter Noyes Elementary School
5th Grade
Sudbury, Massachusetts

Teacher: Michelle Savage

"Have you ever imagined a moon that has “turned around”? If you have, Dione, Saturn’s 4th largest moon, could be the one! Dione was discovered by the Italian scientist, Giovanni Cassini in 1684 and formally named by John Herschel in 1847. Dione with a diameter of 698 miles or 1123 km is the 15th largest moon in our solar system and also one of the denser ones. Dione orbits around Saturn once every 2.7 Earth days (at a distance of 234,000 miles), approximately the same distance from Earth to its moon. Another similarity Dione has with our moon is that it is also “tidally locked”, meaning we see the same side of this moon from Saturn.

In my opinion, Cassini in its next flyby in 2015 should focus its cameras on Target number 2: Dione. There are several questions that scientists need to answer. Was there was ever any life on this icy moon because of the presence of liquid water under its surface or the thin layer of oxygen it its exosphere? I will be amazed if there was evidence of life found on Dione especially if subsurface oceans were ever found on it. This could explain the need to explore icy dwarf planets like Pluto & Ceres that could also have subsurface oceans. Dione also has some large craters up to 62 miles (or 100km) that are located on its trailing hemisphere. However, a moons leading hemisphere should be more heavily cratered, so scientists have formulated a theory that a more recent impact has spun Dione around. This is another mystery that scientists need to solve if a collision has actually spun it. And why is there a spin of exactly 180 degrees?

From images taken by Voyager I in 1980, the wispy terrain on Dione was believed to be ice deposits. But from the recent flybys of Cassini, these wisps are now recognized as bright ice cliffs several hundred meters high. Scientists would like to find out how these cliffs were formed whether by volcanic activity or something else.

I believe that scientists will be able to answer these questions and more if Cassini aims its cameras on Dione. Its impressive cratered surface, wispy terrain, its shift of 180 degrees and the layer of liquid under its surface are all burning questions waiting to be answered. This would be the final opportunity for scientists that Cassini can answer in its last flyby of Dione in 2015. As a young scientist researching about Dione, these questions have often nagged me. I think this presents an amazing educational opportunity for us to learn more about one of the most fascinating moons not only in Saturn’s family but also in our entire solar system."