… If you have thought we were done with Pluto (who dares still calling it a dwarf, planet or anything?), well, get ready. NASA has just revealed another stunning detail sent over by New Horizons in its historical flyby of July, 14 2015: Pluto has blue skies. Yes, exactly, and they look similar in nature to Saturn’s moon Titan.
“Who would have expected a blue sky in the Kuiper Belt? It’s gorgeous. (…) That striking blue tint tells us about the size and composition of the haze particles. (…) 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.” (Alan Stern, New Horizons’ principal investigator, Southwest Research Institute, Boulder, Colorado. Read the press release here).
As if blue skies were not enough, New Horizons also discovered water ice in a few small, concentrated region of the planet’s surface.
The interesting thing about it is that the areas showing the most obvious water ice spectral signatures correspond to the ones that are bright red in Pluto’s images in colour – the now famous picture with the “heart” – due to some not yet understood relationships between water ice and the reddish tholin colorants on the surface.
One thing is certain, though: Pluto’s surprises are not over yet.
(Photo Credits: NASA)