NASA's New Horizons is fast approaching its July 14 encounter with Pluto -- our first ever flyby of the mysterious dwarf planet. As the spacecraft comes closer and closer to completing its decade-long trek, the images we're getting of Pluto and its moons are increasingly clear. In the latest photos, we get a teasing glimpse of just how varied the surface of Pluto is.

As with the last color photo of Pluto and its largest moon, Charon, this new one -- made using images and color data taken June 25 and 27 -- shows a grayish moon and a peachy dwarf planet, a far cry from the cool colors most of us have assigned to Pluto because of its frigid temperatures.

The most exciting development in the new images is a smattering of spots on Pluto's equator. They appear to be evenly spaced and sized, each about 300 miles in diameter.

"It's a real puzzle. We don't know what the spots are, and we can't wait to find out," New Horizons principal investigator Alan Stern said in a statement. "Also puzzling is the longstanding and dramatic difference in the colors and appearance of Pluto compared to its darker and grayer moon Charon."

If all goes well, we'll see even better shots of Pluto in the coming days -- and get the data we need to truly understand the features we spot.

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