As NASA's Dawn spacecraft approaches orbit around the dwarf planet Ceres, researchers aren't sure what's causing the "bright spots" on its surface. The imaging orbiter snapped the above picture from 29,000 miles (46,000 km) away just last week, but until it gets closer for a more detailed picture, the folks at NASA aren't ready to decide the light sources' origin. "The brightest spot continues to be too small to resolve with our camera, but despite its size it is brighter than anything else on Ceres," said Andreas Nathues, a lead investigator at the Max Planck Institute for Solar System Research in Germany. "This is truly unexpected and still a mystery to us."