Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
The surface of Pluto is becoming better resolved as NASA’s New Horizons spacecraft speeds closer to its July flight through the Pluto system. A series of new images obtained by the spacecraft’s telescopic Long Range Reconnaissance Imager (LORRI) during May 29-June 2 show Pluto is a complex world with very bright and very dark terrain, and areas of intermediate brightness in between. These images afford the best views ever obtained of the Pluto system. New Horizons scientists used a technique called deconvolution to sharpen the raw, unprocessed pictures that the spacecraft beams back to Earth; the contrast in these latest images has also been stretched to bring out additional details. Deconvolution can occasionally produce artifacts, so the team will be carefully reviewing newer images taken from closer range to determine whether some of the tantalizing details seen in the images released today persist. Pluto’s non-spherical appearance in these images is not real; it results from a combination of the image-processing technique and Pluto’s large variations in surface brightness. Since April, deconvolved images from New Horizons have allowed the science team to identify a wide variety of broad surface markings across Pluto, including the bright area at one pole that scientists believe is a polar cap. “Even though the latest images were made from more than 30 million miles away, they show an increasingly complex surface with clear evidence of discrete equatorial bright and dark regions—some that may also have variations in brightness,” says New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute, Boulder, Colorado. “We can also see that every face of Pluto is different and that Pluto’s northern hemisphere displays substantial dark terrains, though both Pluto’s darkest and its brightest known terrain units are just south of, or on, its equator. Why this is so is an emerging puzzle.” “We’ve seen evidence of light and dark spots in Hubble Space Telescope images and in previous New Horizons pictures, but these new images indicate an increasingly complex and nuanced surface. Now, we want to start to learn more about what these various surface units might be and what’s causing them. By early July we will have spectroscopic data to help pinpoint that.”
