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At a current distance of 4. 5 billion kilometers from the sun, Pluto isthe only planet in our solar system not yet visited by a spacecraft. Mostmission plans call for a long and expensive journey to the faraway planet.But a recent proposal by scientists at the Jet Propulsion Laboratory (JPL)
At a current distance of 4. 5 billion kilometers from the sun, Pluto isthe only planet in our solar system not yet visited by a spacecraft. Most missions call for a long and expensive journey to the faraway planet.But a recent proposal by scientists at The Jet Propulsion Laboratory (JPL)