Pluto has blue skies and patches of red frozen water, according to the latest data from NASA’s unmanned New Horizons probe, which made a historic flyby of the dwarf planet in July. Never before has Pluto — a resident of the distant Kuiper Belt, a frigid region of the solar system beyond Neptune that is home to many comets and asteroids — been observed in such detail. Along with the announcement, NASA released an image showing a blue layer of haze around Pluto, taken by the New Horizons spacecraft’s camera. Blue skies are seen on Earth because of the scattering of sunlight by very small particles of nitrogen. “On Pluto they appear to be larger — but still relatively small — soot-like particles we call tholins,” science team researcher Carly Howett said.
NASA said the “second significant finding” from New Horizons’ latest trove of data is that there are numerous small, exposed regions of frozen water on Pluto. Using a tool called a spectral composition mapper, scientists have been able to map the signatures of water ice on various parts of the planet’s surface. The areas that seem to contain the most water ice also appear bright red in recent colour images of Pluto. “I’m surprised that this water ice is so red,” science team member Silvia Protopapa said. “We don’t yet understand the relationship between water ice and the reddish tholin colorants on Pluto’s surface.”
Scientists have previously reported seeing flowing nitrogen ice glaciers on the surface of Pluto. On July 14, New Horizons, a nuclear-powered spacecraft about the size of a baby grand piano, became the first spaceship to pass by Pluto. It will continue to send data back to Earth until late next year. NASA said the spacecraft is in good working order about 5 billion kilometres from Earth.
Regions with exposed water ice are highlighted in blue. The strongest signatures of water ice occur along Virgil Fossa, just west of Elliot crater on the left side of the inset image, and also in Viking Terra near the top of the frame. A major outcrop also occurs in Baré Montes towards the right of the image, along with numerous much smaller outcrops, mostly associated with impact craters and valleys.
Just 15 minutes after its closest approach to Pluto on July 14, the New Horizons spacecraft looked back toward the sun and captured this near-sunset view of the rugged, icy mountains and flat ice plains extending to Pluto’s horizon. The smooth expanse of the informally named icy plain Sputnik Planum (right) is flanked to the west (left) by rugged mountains up to 11,000 feet (3,500m) high.
In this extended colour image of Pluto taken by New Horizons, rounded and bizarrely textured mountains, informally named the Tartarus Dorsa, rise up along Pluto’s day-night terminator and show intricate but puzzling patterns of blue-gray ridges and reddish material in between. This view, roughly 330 miles (530 kilometers) across, combines blue, red and infrared images.
Credits: Australian Broadcasting Corp., Mail Online.