CAPE CANAVERAL, Fla. -- Scientists have released the first up-close images ever of Pluto and its big moon Charon. And they say they're amazed.

NASA releases new photos of Pluto

The long-awaited images were unveiled Wednesday in Maryland, home to mission operations for NASA's New Horizons spacecraft.

A zoom-in of Pluto reveals an icy range about as high as the Rockies. To the scientists' great surprise, there are no impact craters. On Charon, deep troughs and canyons can be seen.

The images were collected as New Horizons swept within 12,300 kilometres of Pluto on Tuesday, becoming Pluto's first visitor in its 4.5 billion-year existence.

Scientists didn't know until Tuesday night -- when the spacecraft phoned home -- that the encounter was a success.

New Horizons already is 1.6 million kilometres beyond the dwarf planet, and 4.8 billion kilometres from Earth.