The spacecraft that flew closest to the sun is Parker Solar Probe, launched by NASA in 2018.

Here are some key points about its mission:

* Purpose: To study the sun's corona, the outermost layer of its atmosphere.

* Distance: Parker Solar Probe has made multiple close approaches to the sun, getting as close as 3.83 million miles (6.16 million kilometers).

* Heat shield: It has a special heat shield to protect it from the intense heat and radiation of the sun.

While other spacecraft have flown through the inner solar system, none have come as close to the sun as Parker Solar Probe.