It will get within 9 or 10 Sun-diameters of the "bottom" (the Sun's surface) which seems pretty far when you put it that way, but from up here on Earth it's practically all the way down.

"Parker Solar Probe", by Randall Munroe, licensed under Creative Commons Attribution-NonCommercial 2.5 License

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It will get within 9 or 10 Sun-diameters of the "bottom" (the Sun's surface) which seems pretty far when you put it that way, but from up here on Earth it's practically all the way down.