Pluto Moon(01 of11)
Open Image ModalThis image released by NASA on Thursday, Oct. 1, 2015, shows Charon, in enhanced color captured by NASA's New Horizons spacecraft just before closest approach on July 14, 2015. Massive canyons and fractures are clearly visible on Charon, which is more than half of Plutoâs size. (NASA/JHUAPL/SwRI via AP) (credit:ASSOCIATED PRESS)
Space Pluto(02 of11)
Open Image ModalThis July 14, 2015 photo released by NASA on Thursday, Sept. 17, 2015 shows the atmosphere and surface features of Pluto, lit from behind by the sun. It was made 15 minutes after the New Horizons' spacecraft's closest approach. (NASA/JHUAPL/SwRI via AP) (credit:ASSOCIATED PRESS)
Space Pluto(03 of11)
Open Image ModalThis July 14, 2015 photo released by NASA on Thursday, Sept. 17, 2015 shows the atmosphere and surface features of Pluto, lit from behind by the sun. It was made 15 minutes after the New Horizons' spacecraft's closest approach. (NASA/JHUAPL/SwRI via AP) (credit:ASSOCIATED PRESS)
Pluto(04 of11)
Open Image ModalThis July 14, 2015, photo provided by NASA shows a synthetic perspective view of Pluto, based on the latest high-resolution images to be downlinked from NASAâs New Horizons spacecraft. The new close-up images of Pluto reveal an even more diverse landscape than scientists imagined before New Horizons swept past Pluto in July. (NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute via AP) (credit:ASSOCIATED PRESS)
Pluto(05 of11)
Open Image ModalThis July 14, 2015, photo provided by NASA shows a 220-mile (350-kilometer) wide view of Pluto taken from NASAâs New Horizons spacecraft. The new close-up images of Pluto reveal an even more diverse landscape than scientists imagined before New Horizons swept past Pluto in July. (NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute via AP) (credit:ASSOCIATED PRESS)
Space Pluto(06 of11)
Open Image ModalThis image made available by NASA on Friday, July 24, 2015 shows a combination of images captured by the New Horizons spacecraft with enhanced colors to show differences in the composition and texture of Pluto's surface. The images were taken when the spacecraft was 280,000 miles (450,000 kilometers) away. (NASA/JHUAPL/SwRI via AP) (credit:ASSOCIATED PRESS)
Space Pluto(07 of11)
Open Image ModalThis July 15, 2015 image made available by NASA on Friday, July 24, 2015 shows the atmosphere of Pluto backlit by the sun when the New Horizons spacecraft was about 1.25 million miles (2 million kilometers) away. The image, delivered to Earth on July 23, is displayed with north at the top of the frame. (NASA/JHUAPL/SwRI via AP) (credit:ASSOCIATED PRESS)
Space Pluto(08 of11)
Open Image ModalThis image made available by NASA on Friday, July 24, 2015 shows Pluto made by combining several images from two cameras on the New Horizons spacecraft. The images were taken when the spacecraft was 280,000 miles (450,000 kilometers) away from Pluto. (NASA/JHUAPL/SwRI via AP) (credit:ASSOCIATED PRESS)
Pluto(09 of11)
Open Image ModalThis image was taken on July 14, 2015, by New Horizonsâ Long Range Reconnaissance Imager (LORRI) from a distance of 48,000 miles (77,000 kilometers) shows a newly discovered mountain range near the southwestern margin of Plutoâs Tombaugh Regio (Tombaugh Region), situated between bright, icy plains and dark, heavily-cratered terrain. The image was received on Earth on July 20. (NASA/JHUAPL/SWRI via AP) (credit:ASSOCIATED PRESS)
Pluto(10 of11)
Open Image ModalThis July 14, 2015 photo provided by NASA shows an image taken from NASA's New Horizons spacecraft showing a new close-up image from the heart-shaped feature on the surface of Pluto that reveals a vast, craterless plain. (NASA/JHUAPL/SWRI via AP) (credit:ASSOCIATED PRESS)
Pluto(11 of11)
Open Image ModalThis photo taken Tuesday, July 14, 2015, at approximately 6:30 a.m. EDT, shows Pluto's largest moon Charon, left, with a captivating feature, a depression with a peak in the middle, shown in the upper left corner of the inset image at right. (NASA/JHUAPL/SwRI via AP) (credit:ASSOCIATED PRESS)