An unusual crater on Mars has the boffins puzzled, via io9, original article and image from ESA.
Bad Astronomy has a couple of amazing fire tornado videos - here and here.
Jumbo hailstone from South Dakota - courtesy of Digg.
Neatorama has a rather hypnotic video of our Asteroid discoveries from the last 30 years.
Finally the most detailed image of a sunspot yet from Techvert who have the original, much bigger version.