- Phil Plait at Bad Astronomy has a nice post titled, "The Galilean Revolution, 400 years later". In this post, Plait speculates on just how amazed Galileo would be of our current depth of knowledge of the worlds he discovered, and on Phil's own view of the moons coming up tonight in cold Boulder, CO.
- The editors of 80 Beats have a new Galilean satellites photo gallery consisting of Voyager and Galileo images of the Galilean satellites.
- Mark Thompson, an amateur astronomer who plays Galileo Galilei in a one man show titled Galileo 1610, hosts today's 365 Days of Astronomy podcast, "Are You Sure Those Are Moons by Jove?". The podcast has a few good selections from Galileo's Sidereus Nuncius.
- As I mentioned yesterday, Paul Schenk has posted several videos showing examples of the topography on the Galilean satellites, including Hi'iaka Montes and Tohil Mons on Io, on his blog, Stereo Moons.
- Bing.com, a search engine I don't use, but I may have to now, has a huge pic of Io on its front page to celebrate the Quadricentennial of the discovery of the Jovian moons.
- Jane Jones post a quick missive on the anniversary on the JPL blog.
- Thanks to Emily Lakdawalla for the shout out on her blog to my Io@400 series in her post marking the anniversary.
- Slashdot even has a story up, "400 Years Ago, Galileo Discovered Four Jovian Moons". Be prepared for "That's no moon..." and "Wow, Slashdot is late again..." jokes. You've been warned.
- The blog for the Wolfram|Alpha search engine has a post about the anniversary and how you can use their website to generate plots showing the positions of the Galilean satellites for a particular viewing location and time.
EDIT 01/07/2010 2:33 pm: Added Bing.com commemoration and JPL Blog post. Tip o' the hat to Jani Radebaugh and Daniel Fischer.
Happy Io Discovery Day, everyone!