NASA Finds 'Clear Blue Skies' And Water Ice On Pluto

Pluto probably looks as romantic as the earth! NASA's New Horizons spacecraft has discovered some features of Pluto that look bright and beautiful---"brilliant blue skies and a landscape of water ice".

There are probably "haze particles" around that little planet, which are gray or red, yet scatter blue light enough to catch and hold the New Horizons team's attention, NASA  reported.

"That striking blue tint tells us about the size and composition of the haze particles," said science team researcher Carly Howett, of SwRI  (Southwest Research Institute). "A blue sky often results from scattering of sunlight by very small particles. On Earth, those particles are very tiny nitrogen molecules. On Pluto they appear to be larger - but still relatively small - soot-like particles we call tholins."

Now what on earth---or Pluto---are tholins?

These are thought to be formed right up in the atmosphere, whenever "sunlight ionizes nitrogen and methane molecules". Both molecules undergo chemical interactions and morph into complex negatively and positively charged ions. They then combine once more to become "complex macromolecules" that come closer and again expand to become new particles.

The next stage is the formation of ice frost with volatile gases covering their surface. They then drop through the atmosphere to the surface, which is perhaps the reason why Pluto looks red.

Said Silvia Protopapa, a science team member from the University of Maryland : "I'm surprised that this water ice is so red," she said. "We don't yet understand the relationship between water ice and the reddish tholin colorants on Pluto's surface."

Researchers found a lot of smaller areas that had water ice on Pluto's surface.

"Large expanses of Pluto don't show exposed water ice," said science team member Jason Cook, of SwRI, "because it's apparently masked by other, more volatile ices across most of the planet. Understanding why water appears exactly where it does, and not in other places, is a challenge that we are digging into."