Martian blueberries! Now I have something to add to my cereal.
A strange picture of odd, spherical rock formations on Mars from NASA's Opportunity rover has scientists scratching their heads over what exactly they're looking at.
The new Mars photo by Opportunity shows a close-up of a rock outcrop called Kirkwood covered in blister-like bumps that mission scientists can't yet explain. At first blush, the formations appear similar to so-called Martian "blueberries" -- iron-rich spherical formations first seen by Opportunity in 2004 -- but they actually differ in several key ways, scientist said.