People often ask me to produce one of my scale-comparison montages featuring the small moons of the outer solar system. I'd love to do that, but Galileo's best images of Jupiter's ringmoons lack detail compared to Cassini's images from Saturn.
Now that I have a reasonable-resolution global color view of Pluto, I can drop it into one of my trademark scale image montages, to show you how it fits in with the rest of the similar-sized worlds in the solar system: the major moons and the biggest asteroids.
Simon Kattenhorn and Louise Prockter may finally have found subduction zones on Europa, which would it the only other place in the solar system besides Earth that is known to have active plate tectonics.
It's time to reassess Europa exploration, past, present and future. The Destination Europa! session at AGU, inspired by the eponymous website and movement, didn't take exactly that message as its theme, but it's what I got from the presentations. What an ELECTRIFYING meeting this has been for Europa exploration!
While writing up the cruise-phase issues of the Galileo Messenger a couple of weeks ago, I came across a fuzzy montage of images of Ida that I had not seen before. So I decided to spend some time digging into the Planetary Data System to see if there were more images to be found. I found lots and lots pictures that I'd never seen before!
From 1981 to 1997, the Galileo mission published an approximately quarterly newsletter called the Galileo Messenger. It eventually ran to 45 issues, until the end of the Prime Mission. The first 20 were published before Galileo ever got off the ground. That period is the subject of this post.
Among Europa scientists there are two warring factions: the thick-icers and the thin-icers. The question is how thick is the ice shell that overlies Europa's subsurface ocean (the existence of which pretty much everyone agrees on).