how far away is pluto?
And then at its most distant point of its orbit, called aphelion, Pluto gets to within 7.38 billion km of the Sun. Astronomers use another term to measure distance in the Solar System called âastronomical unitsâ. 1 astronomical unit, or AU, is the average distance from the Earth to the Sun â about 150 million km. Plutoâs perihelion is 29.7 AU, and its aphelion is 49.3 AU. Plutoâs average distance, or semi-major axis, is 39.5 AU.