Millions of miles from Earth, an American space-craft has swung into orbit around a world so different, scientists have struggled to classify it.
Now, scientists are on the verge of uncovering its mysteries.
After launching nearly eight years ago, NASA's Dawn probe began orbiting the dwarf planet, Ceres. Discovered in 1801, Ceres lies in our solar system's main asteroid belt between Mars and Jupiter. Roughly the size of Texas, it was classified as planet for many years, then demoted to an asteroid...and recently reclassified as a dwarf planet.
Dawn will now circle Ceres for 16 months, studying its structure and looking for answers.