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Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ New map reveals geology and history of Pluto's moon Charon

New map reveals geology and history of Pluto's moon Charon



Albedo-based map of Charon's meeting half Albedo is a measure of the amount of light reflecting from a surface. Credit: Robbins, et al., 201
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What a difference a planetary flight city does. Pluto's Moon Charon once more than a fuzzy lump of pixels beside a major blob-now has its first geological map, published in AGUs Journal of Geophysical Research : Planets .


The new map was made with data and images collected by 2015 flyby of New Horizon's spacecraft, which managed to collect enough data to map approx. one third of Charon's surface.

In this area, researchers have identified 16 different types of geological units or areas with similar landscapes along with 10-kilometer-long rocks; more than a thousand grooves and other long linear features; and a patchwork of light and dark earth.

To get cliffs, troughs, craters and other functions, the team used several pictures of Charon taken as the spacecraft flew past to create stereo 3-D images. These images are taken from different positions so they can be treated with the same principle that our own brain uses to take pictures from two eyes and give us depth perception.

The new map shows possible evidence for a world that may have once been divided as a thin lip, or a rising cake, then release icy materials from its interior to flood over vast areas – called cryoflows. In fact, scientists have found that Charon may have been one of the most compelling examples of large cryoflows found in the solar system.

Crater Enigma

The new card has revealed many enigmatic features of Charon, including its craters.

Geomorphological unit map of Charon's half-section in (A) cropped Molleweide projection and (B) polar stereographic projection. Credit: Robbins, et al., 2019

"Surprisingly, we see very, very few broken craters," says Stuart Robbins of the Southwest Research Institute and leads the author of the new paper. "On Mars we see old (broken down) and new craters. At Charon, virtually every crater looks like it was created recently." Whether they or the craters they see have been around for a long time without changing anything, he added.

An explanation for the lack of old craters could be that some process delete the older craters. This process can be old icy streams – cryoflows – that broke up through cracks in the surface of Charon and buried the older craters.

If that were the case, perhaps perhaps in Charon's past, warming up his interior and undergoing chemical or physical change made it expand slightly. This extension cracked the surface – analogous to how the surface of a cake tore when the cake rises while baking explains, Robbins explains. Then, warmer materials were down below Charon's surface. That material would have hidden much of Charon's original surface along with craters that were on the surface. This will also explain features that resemble broken blocks of the lunar crust trapped and surrounded by a river of fresher materials.

Oz, Vulcan and Spock

To organize Charon's functions based on cryoflows, the authors of the Map described and named three major epochs in Charon's history: Ozian, Vulcanian and Spockian.

Formula and informal nomenclature for regions and traits of Charon used in the new map. Oz includes mid to high latitudes. Volcano includes equatorial and near-equatorial regions.

The Ozian era was more than 4 billion years ago when the informal named Oz Terra part of the Charon chimney was formed, shown on the top of the map.

The volcanoes came next, perhaps more than 4 billion years ago too, with cryoflows forming Vulcan Planum in the lower part of the map, near Charon & # 39; s equator. Volcanoes probably continued for some time as various parts of Charon cooled.

The final epoch, the Spockian, represents the time after the volcano palm solidified. This is the period when the same area was pockmarked with battlegrounds so far.

This is just a possible plot for Charon's story, Robbins points out.

"We could be completely wrong," he said. said about cryoflows.

It is a question that planetary scientists can ponder over while awaiting more data from Charon, which can be a very long time since no follow-up missions are currently in the works for the very far part of the solar energy system.


Explore further:
Picture: The youngest crater on Charon?

More Information:
Stuart J. Robbins et al. Geological landforms and chronological history of Charon as revealed by a hemispherical geological map, Journal of Geophysical Research: Planets (2019). DOI: 10.1029 / 2018JE005684

Journal reference:
Journal of Geophysical Research

Provided by:
American Geophysical Union


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