To a nearly all-black audience at MarsHill Baptist Church in Chicago, Obama declared: "I am not running a race-based campaign. I am rooted in the African-American community, but not limited by it."
In one photo, a hill on Mars' surface looked a little like a face.
在一张照片中，火星表面的一座山看上去有点像一张脸。
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So says Jonathon Hill, a research technician and mission planner at the Mars Space Flight Facility at Arizona State University, which operates many of the cameras used during NASA's Mars missions.