The Spirit rover on Mars took the first picture of Earth ever made from the surface of another planet. It also did a little astronomy, imaging bright stars. It also spotted what could be a Viking Orbiter spacecraft or a meteor — scientists aren’t sure which. The photo of Earth shows the planet as a bright dot above the horizon about an hour before sunrise. The image is not in color, though scientists say if a human stood in the same spot and looked earthward, home would probably appear pale blue.