Astronomy Picture of the Day

Explanation: Get out your red/blue glasses and gaze across Ceres at mysterious mountain Ahuna Mons. Shown in a 3D anaglyph perspective view, the mosaicked image data was captured in December of 2015, taken from the Dawn spacecraft's low-altitude mapping orbit about 385 kilometers above the surface of the dwarf planet. A remarkable dome-shaped feature on Ceres, with steep, smooth sides Ahuna Mons is about 20 kilometers (12 miles) in diameter at its base, rising on average 4 kilometers to a flattened summit. Similar in size to mountains found on planet Earth, no other Cerean surface feature is so tall and well-defined. It is not known what process shaped the lonely Ahuna Mons, or if the bright material streaking its steepest side is the same material responsible for Ceres' famous bright spots.