Free Astronomy Magazine March-April 2019

T his close-up view of a target rock called Last Chance was acquired by the microscopic im- ager on Opportu- nity's arm on March 3, 2004, during its 39th Martian day. The area covered in the view is about 2 inches (5 cen- timeters) across. The embedded spherules evi- dent in this image reminded researchers of berries in a muf- fin, so they were nicknamed “blueberries.” These mineral concretions and other textures in this rock provided evidence about wet environmental conditions in the ancient past in the Meridiani Planum region. [NASA/JPL-Caltech/Cornell Univ./USGS] T owards the right side of this enhanced-color scene is a broad notch in the crest of the west- ern rim of Endeavour Crater. Wheel tracks in that area were left by Opportunity as it ob- served Perseverance Valley from above. Opportunity’s Pancam took the component images for this view from a position outside the crater during the span of June 7 to June 19, 2017, sols 4753 to 4765 of the rover’s work on Mars. [NASA/JPL-Caltech/Cornell/Arizona State Univ.]