when did voyager 1 leave our solar system
August 25, 2012
Voyager 1
 "Voyager 1" crossed the heliopause and entered interstellar space on August 25, 2012, making it the first spacecraft to do so.
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Voyager 1 [SEP] Introduction
Although the spacecraft's course could have been altered to include a Pluto encounter by forgoing the Titan flyby, exploration of the moon took priority because it was known to have a substantial atmosphere. Voyager 1 studied the weather, magnetic fields, and rings of the two planets and was the first probe to provide detailed images of their moons. As part of the Voyager program, like its sister craft "Voyager 2", the spacecraft is in an extended mission to locate and study the regions and boundaries of the outer heliosphere, and to begin exploring the interstellar medium. "Voyager 1" crossed the heliopause and entered interstellar space on August 25, 2012, making it the first spacecraft to do so.