I've just posted my annual roundup of significant images from planetary exploration in 2010. I make no claims for these being the "best of 2010" -- the images are selected more to mark significant events in 2010, though I confess some are just chosen because they're spectacular. And anyway, this is space exploration; I think all the images are spectacular.
NASA / JPL / SSI / color composite by Gordan Ugarkovic
Enormous storm on Saturn
On December 24, 2010, Cassini captured its first complete photos of a massive storm on Saturn that had already captured the fascination of amateur astronomers. The storm was first noticed on December 5 by the Radio and Plasma Wave Science (RPWS) team on Cassini, who detected its lightning emissions and alerted astronomers. Amateur astronomers photographed it shortly after.
Our LightSail test mission was successfully completed and our Kickstarter campaign ended June 26th, raising $1.24 million dollars for LightSail's 2016 solar sailing mission! Miss the Kickstarter campaign, but still want to donate? You can!