Image Credit & Copyright: NASA/JPL/Space Science Institute/Cassini.
Here’s a special treat today. I was just thumbing through some images that I had from Cassini and I came across this wonder inspiring image taken by the Cassini spacecraft on January 11, 2011. Let’s put some 3D into this image and see what we’ve got here.
First things first, that big rock at the top of the image is the south polar region of Saturn’s moon Rhea which is 1,528 km (949 mi.) in diameter and shot from a distance of 61,000 km (38,000 mi.). An interesting fact is that Saturn never gets to see this side of Rhea as, like our Moon it only ever shows one face to its host planet.
All the way across the thin silver line that is the rings of Saturn is another of Saturn’s moons, Dione. This moon is 1,123 km (698 mi.) in diameter and shot from a distance of 924,000 km (574,000 mi.). In this case, Dione is showing us its Saturn side as Saturn never gets to see what’s on the other side of Dione.
Some might infer that, at first glance, our Moon is special in that we never see the far side of it. Note that I didn’t say “dark side” as days and nights on our Moon last roughly 14 days and all faces of the Moon get equal sunlight. Well, you might be oddly surprised to know that 16 of Saturn’s 53 named moons and 9 provisional moons (62 total) are tidally locked with the planet. That’s 16 moons in orbit around Saturn that act just like our Moon by only showing one side of itself to its host…..pretty cool.
JPL Photojournal page for this image: http://photojournal.jpl.nasa.gov/catalog/PIA12755
CICLOPS: Cassini official imagery site: http://ciclops.org/?js=1
JPL Cassini mission images: http://saturn.jpl.nasa.gov/photos/
JPL RAW Cassini images: http://saturn.jpl.nasa.gov/photos/raw/
The Planetary Society “Bruce Murray Space Image Library” Cassini Images (Great Source): http://www.planetary.org/multimedia/space-images/saturn/?keywords=cassini
ESA Cassini mission page: http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens/Cassini_spacecraft
NASA Solar System (Saturn’s Moons): http://solarsystem.nasa.gov/planets/profile.cfm?Object=Saturn&Display=Sats