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In 2015, scientists got their best glimpse yet of dwarf planets, when two NASA spacecraft visited distant worlds. In March, the Dawn mission arrived at Ceres, which lies in the asteroid belt between Mars and Jupiter; water ice may lurk under the protoplanet's crust. On 14 July, the New Horizons spacecraft reached the far edge of the Solar System, buzzing by Pluto before continuing on to the Kuiper belt.