Safronov Regio (formerly Krun Macula) is the westernmost of the "Brass Knuckles", a series of equatorial dark regions on Pluto.

Safronov Regio was first observed as the New Horizons spacecraft approached Pluto and its system of moons.

As Pluto rotated, a series of equatorial dark regions were observed and informally nicknamed the Brass Knuckles,[2] with Safronov Regio being the westermost of the dark regions.

[3][4] However, the International Astronomical Union (IAU) instead officially approved the name Safronov Regio in honor of Russian astronomer Viktor Safronov, an early proponent of the planetesimal hypothesis for Solar System formation.

Krun Macula is the name of one of the ship of the character Pluto in Heaven Will Be Mine, a 2018 visual novel.