Pluto New Horizons
New Horizons images of Pluto and Charon taken at 13 times from April 12 to April 18, 2015. The view of Pluto in the lower-right inset, highlights the increased brightness at its visible pole, which scientists suggest might be caused by a "cap" of highly reflective snow on the surface. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

New images of Pluto released April 29 suggest the dwarf planet has a polar ice cap.

That cap, and other features, were seen in images taken by NASA’s New Horizons spacecraft that for the first time offer better resolution than images from the Hubble Space Telescope.

Scientists said they do not know yet if bright and dark features seen in the images represent differences in composition or in topography.

The images were captured by New Horizons’ Long-Range Reconnaissance Imager in early to mid-April when the spacecraft was still some 113 million kilometers from Pluto. Launched in 2006, New Horizons will make its closest approach to the dwarf planet in mid-July.

“After traveling more than nine years through space, it’s stunning to see Pluto, literally a dot of light as seen from Earth, becoming a real place right before our eyes,” Alan Stern, New Horizons principal investigator at Southwest Research Institute in Boulder, Colorado, said in a statement. “These incredible images are the first in which we can begin to see detail on Pluto, and they are already showing us that Pluto has a complex surface.”