After over nine years of travel, NASA's New Horizons spacecraft is starting to provide hints of what its July flyby of Pluto will reveal. Earlier this month, the unmanned probe sent back the clearest images yet of the most distant planet of the classic Solar System, which have revealed light areas on the surface that show it may have polar caps.
The new images were captured in mid-April at a distance of 70 million miles (113 million km) from the dwarf planet by New Horizons' Long-Range Reconnaissance Imager (LORRI) camera. The images were sharpened using image deconvolution, which is a technique that reverses image jiggling and optical distortions by means of a digital algorithm that makes statistical comparisons of multiple images.
The result is low-definition images and animations of Pluto showing light and dark areas, with the bright spots indicating what may be polar caps. Whether these exist or are made of ice or frozen gases has still to be determined. In addition, LORRI took images of Pluto's moon Charon, but NASA says that the exposure times were too short to see the planet's four other moons.
The US$650 million New Horizons mission was launched January 19, 2006 atop an Atlas V rocket from Cape Canaveral, Florida and the spacecraft has so far traveled 3 billion miles (4.8 billion km). The 1,054-lb (478-kg) nuclear-powered probe is on a 9.5-year mission to fly by Pluto and then on to study selected objects in the Kuiper Belt. Sent on a slingshot trajectory using the gravitational pull of Jupiter, New Horizons passed the orbit of Neptune on August 24 last year and will rendezvous with Pluto on July 14 2015, which it will pass at a distance of 8,000 miles (13,000 km).
"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," says Alan Stern, New Horizons principal investigator at Southwest Research Institute in Boulder, Colorado. "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."
Image detail will increase as the closer the spacecraft draws to the July rendezvous.