However, data from New Horizons shows that Pluto and Charon actually have very similar densities, meaning that the original two bodies were also similar.
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In 1996, the world got its first look at the surface of Pluto through the Hubble Space Telescope.
NASA’s New Horizons spacecraft discovered a staggering diversity of terrain during its close approach on July 14, from towering water-ice mountains to a vast, crater-free plain largely divided into mysterious “cells” dozens of kilometers wide. All the same, its arrival, on July 14, 2015 at 7:49 AM ET was precisely on-time, as the spacecraft skimmed by Pluto at the relative treetop level of just 7,800 Michigan.
At the moment, New Horizons is speeding through the Kuiper Belt, getting farther away from Earth, while beaming back data collected during its Pluto flyby.
“The New Horizons encounter with the Pluto system revealed a wide variety of geological activity – broadly taken to include glaciological and surface-atmosphere interactions as well as impact, tectonic, cryovolcanic, and mass-wasting processes on both the planet and its large satellite Charon”, they write.
New Horizons is now on course for its next rendezvous in 2019, with an object called 2014MU69 in the Kuiper belt, which lies beyond the orbit of Neptune.
“The Pluto system surprised us in many ways, most notably teaching us that small planets can remain active billions of years after their formation”, said Stern.
With this first batch of science out from the mission, it will certainly not be the last.
“Pluto’s engine is still running”, said Alan Stern, the Southwest Research Institute scientist who conceived and led NASA’s New Horizons mission to Pluto. If team members identified a possible moon or debris in an image and fit an orbit to the object, Hamilton used the University of Maryland’s new Deepthought2 supercomputer to predict how much debris might be released from the object and hit the spacecraft as it traveled through five possible trajectories.
“For Pluto, the rugged mountains and undulating terrain in and around TR (Tombaugh regio) require geological processes to have deformed and disrupted Pluto’s water ice-rich bedrock”. On Pluto, nitrogen freezes into a soft, mushy substance in which water ice floats.
Stern said the data will answer a few of the questions raised in this initial paper. No other moons, or any evidence of a ring system, have been seen.
“You can even have an interesting sort of [heat] storage mechanism”, McKinnon told Space.com. So, perhaps there’s heat beneath the surface of Pluto.
Pluto’s atmosphere contains volatile chemicals such as methane, nitrogen and carbon monoxide. We have received only a glimpse of its largest moon, Charon, but it is a breathtaking one.
A false-color image of Pluto and Charon exaggerates differences to make features easier to see.
Pluto’s atmosphere is extremely thin.
Mountains, plains, glaciers, a wispy atmosphere, and substantial color variation have appeared in images of Pluto captured by NASA’s New Horizons probe. It also studied Charon and Pluto’s smaller moons Nix, Hydra, Styx and Kerberos.
As seen above, Charon has a fairly tiresome, grey colouration, except for the dark reddish polar region.
The New Horizons spacecraft will send back higher resolution images, which will show exquisite new details of a world that is more lovely than anyone had ever imagined.
“Energetic radiation falling on Pluto’s atmosphere and surface, each rich in nitrogen and methane, likely creates tholins that even in small concentrations yield colors ranging from yellow to dark red”, they wrote.
That little world won’t inspire the love that has come Pluto’s way-and it surely won’t be stamped with the serendipitous heart to prove it. Good science isn’t always going to make good poetry-but as with the dispatches from Pluto, it’s awfully nice when it does.
The measurement reveals that Pluto is only about 10 percent denser than Charon, McKinnon said. Pluto is a coppery, while Charon is a boring gray-just one reason scientists are surprised by how very different these two little worlds are. And Pluto’s surface could still be undergoing such changes, the scientists write in their paper.
But, in keeping with Pluto’s puzzling nature, there’s more to the story here as well – namely, the apparently icy makeup of Nix, Hydra and Styx, which are thought to be shrapnel thrown off by the giant impact. Also visible in the area are apparent glaciers made up of nitrogen, methane and carbon monoxide ices that appear to flow around obstructions. “It’s not all obvious how everything fits together”.
“The Pluto system is much more complex than I had expected”.
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“The mountains detected by New Horizons imagery therefore imply the presence of a widespread, stronger, presumably water ice-based, solid ‘bedrock.’ We further conclude that the observed N2, CO, and CH4 ices must only be a surface veneer above this bedrock”.
