Dione

Source: NASA

Dione, isn’t that graceful?!  This one’s full of character with icy wisps and cliffs.  She’s a smaller moon, but still the 15th largest in the solar system (349 miles)!

What’s neat is that Dione’s avg. distance to Saturn is almost identical to the distance the moon orbits us.  The satellite is made up of mostly ice + a little rock, coming in a chilly -121 degrees F. Yowza.  The moon is completely plummeted with craters, some as large as 62 freaking miles.  What’s odd is that Dione has two types of terrain: heavily cratered and less cratered.  The more cratered area is on the trailing hemisphere, and the less on the leading hemisphere…and these two should be reversed.  We believe that millions of years ago, this moon probably did a 180 from some sort of super intense impact (still a mystery).  But it’s stayed in reverse fashion for millions of years.  I don’t think you have to be a space nerd to think that’s awesome.  The most stand-out feature on Dione though is without a doubt its “wisps.”  These canyon ice walls, hundreds of miles long, form from cracking on the surface due to internal activity.  I love the names these moons adopt, “tiger stripes,” and “wisps.”  Think: the mysterious red fractures on Europa…kinda the same.  Dione, just like Tethys has a subsystem of its own.  Its two moons, Helene and Polydeuces (haha), orbit Saturn locked with Dione (also known as Lagrangian points…I’ll spare you the deets, feel free to look ‘em up!).  As I was researching this one I kept getting a visual of Mann’s planet from Interstellar (for those of you who know me IRL know I am addicted to this movie).  One last cool feature is that Cassini traced a thin layer of molecular oxygen ions…in case I lost you there, that just means it has an exosphere- not quite an atmosphere, still really cool.  The facts go on, and this moon is no less stunning that the ones before it.  Hands in the air if you’re loving the Saturnian system so far!! We aren’t even finished yet.