Ceres has a Mystery Bright Spot: What is it?

As the Dawn Spacecraft readies for orbit insertion only a week from now, the images coming in are getting sharper and sharper.  Once the craft is fully in orbit its first task will be to map the surface of the planet in high definition.  Even on the last few weeks of the journey to Ceres, we have seen increasingly clear images, and have already started asking ‘What the heck is that?’ This week’s ‘what the heck are we looking at?’ involves this apparent double bright spot on Ceres, imaged on February 19th from a distance of 46,000 Km, about an...