New images of Pluto and its moons are among the sharpest ever made, astronomers announced today.
Pluto, long called a planet, was downgraded last year to "dwarf planet" status by the International Astronomical Union. It is so far away that no clear pictures of it exist.
The new images are 20 times brighter than those taken of Pluto 30 years ago when its large moon Charon was discovered. The resulting snapshots are expected to bring astronomers closer to estimating the sizes of Pluto's satellites, Nix, Hydra and Charon.
"Several favorable factors occurred simultaneously to yield these spectacular images of the Pluto system," said astronomer David Tholen, who performed the observations during an early September evening with one of Mauna Kea's twin Keck telescopes.
Tholen relied on the adaptive optics system of Keck, which compensates for turbulence from Earth's atmosphere that typically blurs the light from celestial bodies. In addition, Pluto was at its maximum brightness that night, giving the adaptive optics "stellar" conditions.
He took 16 images of the system and combined them into a single picture, resulting in clear views of Nix and Hydra, Pluto's small satellites that were discovered in 2005 with the Hubble Space Telescope.