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The first high-resolution images of Pluto from New Horizons give astronomers a glimpse of the complex geology of the world's dwarf ice.
The white heart shape was the most striking element of Pluto because the New Horizons spacecraft was still millions of kilometers away, and that is why astronomers l? named after the discoverer of the planet, Clyde Tombaugh.
In addition, the region has an incredible and complex geology.
"There are mountains in the Kuiper belt," said New Horizons principal investigator Alan Stern at 3 pm EDT press conference today. Astronomers expect these mountains to reach an altitude of 11,000 feet (3,300 meters). And these awesome features are most likely made up of water ice – a substance known to occupy the interior of Pluto but which has not yet been conclusively detected on the surface. Still, water is the only way to get those mountains, thinks the team.
Stern said that he had submitted an article to The Astrophysical Journal in May predicting these characteristics, which had been accepted earlier in the day. The editor of the magazine has learned that the ice mountains from the press conference
Because nitrogen and methane are found on the surface young, a kind of glacial volcanism is probably present even though it has not yet been detected. The images of New Horizons will be meticulously researched to look for signs of such activity.
"What is most striking geologically is that we have not yet found a single element of impact on this image," says John Spencer, member of the New Horizons science team. "Just look at it, we think it must be less than 100 million years old, which is a small fraction of the age of the solar system – it could be active right now. "
And the high resolution The image is only one among many others to come
The Dark Spot of Charon, whom mission scientists have now dubbed "the Mordor," remains intriguing in the last picture of Pluto's largest moon.
Charon may have been outclbaded by Pluto, but another incredible discovery announced today is that the moon of the dwarf planet is also active. Recent images seemed to indicate that Charon was old and crater.
"I thought Charon could be an old crater-covered land," said New Horizons scientist Cathy Olkin. "Charon blew our socks when we got the new image today."
"We think the dark coloring could be a thin veneer," she said.
Will Grundy of Lowell Observatory The New Horizons surface composition team said earlier in the day that some Charon images give the impression that the feature film looks like a pond. impact, which might at first surprise to find the pole perfectly. But if the impact was significant enough, the moon could have turned to put it at the pole.
The moon also has a mbadive canyon four to six miles deep that looks like features seen on the Uranus moons, as well as the moon of Saturn Tethys. Astronomers are still trying to break the puzzle of how it's formed, but one theory they play with is a mbadive impact that has temporarily melted Charon's inside. When the moon melts and regenerates, expansion and contraction may have caused cracks.
Olkin shows a series of troughs moving from north-east to south-west over Charon which extends for 600 miles across the moon. And just below the region, there is a line that is relatively smooth, involving a kind of geological activity
that leaves the little world with deep canyons, hollows, cliffs and dark areas and mysterious
. early images of the four small moons of Pluto, which still look like pixilated balloons.
"Let's not forget that Pluto also has 4 small moons," said Hal Weaver, a scientist with the New Horizons mission. He noted that Hydra looks surprisingly bigger than expected.
"This can only mean that Hydra's surface is mainly composed of water ice," he explains.
Pluto undeniably resembled Mars in images of New Horizons. those published today, but the high-resolution images show that the similarities between the Earth's neighbor and the "other red planet" end there.
Pluto's surface is entirely composed of ice. Laboratory simulations coupled with telescope observations suggest that the surface is composed of about 90% nitrogen and about 10% methane.
This means that everything you see on Pluto – all craters, canyons, ice caps – dunes, mountains, tectonics and everything else – unfolds in a complex ice veneer at the top of the ice. a core of ice water.
"Your brain wants to make ice and dark things, but I do not know if that's fine," Grundy said. "Instead, the color variations are all likely ice of different ages. Grundy thinks that "in the most appropriate way", the icy mantle of the dwarf planet could be exposed in the form of heart.
But it is not yet known how these basic ingredients mix and react to form Pluto's complex geology
"Pluto has so much diversity, so we're seeing so many different features," said Alice Bowman, mission operations manager at New Horizons, "There's nothing like that."
Grundy says his team has been looking for ice that could serve as a bedrock – a more permanent ice, but this morning the mission scientists said they had not been able to 39, identify non-ice volatile, that is to say, those which would not sublimate and would not turn into gas under the radiation of the Sun
. the surface could completely upset the views of humanity on the outer solar system.
"There is a lot of heat in an inner ocean," Grundy added, speculating that it could also create tectonic forces. ] Pluto071315_color "width =" 600 "height =" 472 "/>
"When you see something red in the outer solar system, it's usually an indication that the object is covered with complex organic molecules," said the astronomer of the day. North Arizona, Stephen Tegler. He heads the Ice Astrophysics Laboratory at Northern Arizona University, where he works with Grundy and other astronomers to simulate Pluto's surface so New Horizons knows what he's looking for.
Sunlight moves into the Pluto space and the blue rays are absorbed, leaving the red light to our eyes.
"One of the things that can really effectively absorb blue are complex organic molecules," he said. "An easy way to generate them would be to take something like methane and hit it with particles or UV rays; you can break it down and form more complex molecules.
"Red things are chemically very, very interesting, whatever it is," he adds.
In addition, astronomers have used Earth-based telescopes to clbadify the colors of Kuiper Belt Objects (KBOs) as Pluto. Some of the most red objects of all are "frontaures", frozen planetesimals that turn between Jupiter and Neptune. Tegler is also a leading expert on the color of KBOs and Centaurs. Pluto has long been known to have a red hue, but the astronomer says it's not so red compared to other KBOs.
"Pluto is not an object that we would call red in our investigations of Kuiper Belt objects," he says, "and there are centaurs that we would consider much redder than Pluto."
"If Pluto is really considered red when we are going to see it, what does it mean when we go to see some of these other objects?" [19659004] Eric Betz is Associate Editor of Astronomy Follow him on Twitter: @ericbetz
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