View larger. | Remember the beautiful image of the heart-shaped feature on Pluto? Here it is in closer detail. This image covers an area 1,100 miles (1,800 kilometers) across. Scientists call the heart-shaped feature Tombaugh Regio; it’s a smooth, icy plain. Image via NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.

View larger. | The left side of Pluto’s “heart,” in even more detail. Image via NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.

View larger. | A closer view of the border region of the Pluto’s “heart.” There are mountain ridges and other kinds of elevated terrain here, a landscape that scientists call a “chaos region.” Image via NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.

View larger. | Some regions on Pluto are much darker than others. Scientists aren’t sure why. Image via NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.

View larger. | The twilight region on Pluto, where day meets night. Image via NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.

View larger. | Two versions of Pluto’s night side, with its strange haze layer. New Horizons captured the image while looking back at Pluto, as it was leaving this world behind. The lefthand image underwent only minor processing. On the right – if you click into the larger view – you’ll see not just one haze layer but several, made visible by special processing. You can see subtle parallel streaks in the haze, which scientists say, may be crepuscular rays: shadows cast on the haze by Pluto’s mountains. Image via NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.