{"id":11724,"date":"2015-11-09T14:34:19","date_gmt":"2015-11-09T19:34:19","guid":{"rendered":"http:\/\/hobbyspace.com\/Blog\/?p=11724"},"modified":"2015-11-09T14:34:40","modified_gmt":"2015-11-09T19:34:40","slug":"new-horizons-latest-results-include-possible-ice-volcanoes-geology-ancient-and-young-spinning-moons-and-more","status":"publish","type":"post","link":"https:\/\/hobbyspace.com\/Blog\/?p=11724","title":{"rendered":"New Horizons: Latest results include possible ice volcanoes, geology ancient and young, spinning moons, and more"},"content":{"rendered":"

At an\u00a0American Astronomical Society (AAS) Planetary Sciences Meeting<\/a>\u00a0today, the New Horizons<\/a> team brought a truckload\u00a0of\u00a0results to present from the probe’s flyby of the Pluto system. Copies of their presentation slides are available at:\u00a0Science Results from the New Horizons Encounter with Pluto – Presentations – New Horizons<\/a>.<\/p>\n

An\u00a0overview of the findings was released:<\/p>\n

At Pluto, New Horizons Finds Geology of All Ages,
\nPossible Ice Volcanoes, Insight into Planetary Origins<\/a><\/strong><\/p>\n

From possible ice volcanoes to geologically diverse surfaces to oddly behaving moons that could have formed through mergers of smaller moons, Pluto system discoveries continue to surprise scientists on NASA\u2019s New Horizons mission team.<\/p>\n

\u201cThe New Horizons mission has taken what we thought we knew about Pluto and turned it upside down,\u201d said Jim Green, director of planetary science at NASA Headquarters in Washington. \u201cIt\u2019s why we explore \u2013 to satisfy our innate curiosity and answer deeper questions about how we got here and what lies beyond the next horizon.\u201d<\/p>\n

\"Mountains1[1]\"<\/a>
The informally named feature Wright Mons, located south of Sputnik Planum on Pluto, is an unusual feature that\u2019s about 100 miles (160 kilometers) wide and 13,000 feet (4 kilometers) high. It displays a summit depression (visible in the center of the image) that’s approximately 35 miles (56 kilometers) across, with a distinctive hummocky texture on its sides. The rim of the summit depression also shows concentric fracturing. New Horizons scientists believe that this mountain and another, Piccard Mons, could have been formed by the ‘cryovolcanic’ eruption of ices from beneath Pluto’s surface. Credit: NASA\/Johns Hopkins University Applied Physics Laboratory\/Southwest Research Institute<\/em><\/figcaption><\/figure>The New Horizons team is discussing numerous findings at the 47th Annual Meeting of the Division for Planetary Sciences (DPS) of the American Astronomical Society (AAS) this week in National Harbor, Maryland. Just four months after the spacecraft encountered Pluto, science team members are presenting more than 50 reports on exciting discoveries.<\/p>\n

\"CryoVolcanism_Mountains-Rt-txt[1]\"<\/a>
Scientists using New Horizons images of Pluto\u2019s surface to make 3-D topographic maps have discovered that two of Pluto\u2019s mountains, informally named Wright Mons and Piccard Mons, could possibly be ice volcanoes. The color is shown to depict changes in elevation, with blue indicating lower terrain and brown showing higher elevation; green terrains are at intermediate heights. Credit: NASA\/Johns Hopkins University Applied Physics Laboratory\/Southwest Research Institute. Version with no captions<\/a>.<\/em><\/figcaption><\/figure>\u201cIt\u2019s hard to imagine how rapidly our view of Pluto and its moons are evolving as new data stream in each week. As the discoveries pour in from those data, Pluto is becoming a star of the solar system,\u201d said mission Principal Investigator Alan Stern of the Southwest Research Institute, Boulder, Colorado. \u201cMoreover, I\u2019d wager that for most planetary scientists, any one or two of our latest major findings on one world would be considered astounding. To have them all is simply incredible.\u201d<\/p>\n

In one such discovery, New Horizons geologists have combined images of Pluto\u2019s surface to make 3-D maps that indicate that two of Pluto\u2019s most distinctive mountains could be cryovolcanoes\u2014ice volcanoes that may have been active in the recent geological past.<\/p>\n

The two cryovolcano candidates are large features measuring tens of miles (tens of kilometers) across and several miles or kilometers high. \u201cThese are big mountains with a large hole in their summit, and on Earth that generally means one thing\u2014a volcano,\u201d said Oliver White, New Horizons postdoctoral researcher with NASA\u2019s Ames Research Center, Moffett Field, California. While their appearance is similar to volcanoes on Earth that spew molten rock, ice volcanoes on Pluto are expected to emit a somewhat melted slurry of substances such as water ice, nitrogen, ammonia, or methane on Pluto.<\/p>\n

\"Pluto_Crater_Counts_rectangular_projection[1]\"<\/a>
Locations of more than 1,000 craters mapped on Pluto by NASA\u2019s New Horizons mission indicate a wide range of surface ages, which likely means that Pluto has been geologically active throughout its history. Credit: NASA\/Johns Hopkins University Applied Physics Laboratory\/Southwest Research Institute<\/em><\/figcaption><\/figure>White stresses that the team\u2019s interpretation of these features as volcanoes is tentative. However, \u201cIf they are volcanic, then the summit depression would likely have formed via collapse as material is erupted from underneath.\u00a0The strange hummocky texture of the mountain flanks may represent volcanic flows of some sort that have travelled down from the summit region and onto the plains beyond, but why they are hummocky, and what they are made of, we don’t yet know.\u201d<\/p>\n

If Pluto is proven to have volcanoes, it will provide an important new clue to its geologic and atmospheric evolution. \u201cAfter all, nothing like this has been seen in the deep outer solar system,\u201d said Jeffrey Moore, New Horizons Geology, Geophysics and Imaging team leader, also from NASA Ames.<\/p>\n

Pluto\u2019s Long History of Geologic Activity<\/strong><\/p>\n

Another of the more surprising findings from New Horizons is the wide range of surface ages found on Pluto, from ancient to intermediate to relatively young in geological terms. Crater counts used to determine surface unit ages indicate that Pluto has ancient surface areas dating to just after the formation of the planets, about 4 billion years ago. In addition, there\u2019s a vast area that was geologically born \u201cyesterday,\u201d meaning it may have formed within the past 10 million years. This area \u2013 informally named Sputnik Planum \u2013 appears on the left side of Pluto\u2019s \u201cheart\u201d and is completely impact-free in all images returned to date.<\/p>\n

Scientists wondered if Sputnik Planum\u2019s smooth, icy plains were an oddity; did a recent geological episode form the plains long after all other geologic activity ceased?<\/p>\n

Apparently not. New data from crater counts reveal the presence of intermediate or \u201cmiddle-aged\u201d terrains on Pluto as well. This suggests that Sputnik Planum is not an anomaly\u2014that Pluto has been geologically active throughout much of its more than 4-billion-year history. \u201cWe\u2019ve mapped more than a thousand craters, which vary greatly in size and appearance,\u201d said postdoctoral researcher Kelsi Singer, of the Southwest Research Institute (SwRI) in Boulder, Colorado. \u201cAmong other things, I expect cratering studies like these to give us important new insights into how this part of the solar system formed.\u201d<\/p>\n

Building Blocks of the Solar System<\/strong><\/p>\n

Crater counts are giving the New Horizons team insight into the structure of the Kuiper Belt itself. The dearth of smaller craters across Pluto and its large moon Charon indicate that the Kuiper Belt likely had fewer smaller objects than some models had predicted. This leads New Horizons scientists to doubt a longstanding model that all Kuiper Belt objects formed by accumulating much smaller objects of less than a mile wide. The absence of small craters on Pluto and Charon support other models theorizing that Kuiper Belt objects tens of miles across may have formed directly, at their current\u2014or close to current\u2014size.<\/p>\n

In fact, the evidence that many Kuiper Belt objects could have been \u201cborn large\u201d has scientists excited that New Horizons\u2019 next potential target \u2013 the 30-mile-wide (40-50 kilometer wide) KBO named 2014 MU69 \u2013 which may offer the first detailed look at just such a pristine, ancient building block of the solar system.<\/p>\n

Spinning, Merged Moons<\/strong><\/p>\n

The New Horizons mission is also shedding new light on Pluto\u2019s fascinating system of moons and their unusual properties. For example, nearly every other moon in the solar system, including Earth\u2019s moon, is in synchronous rotation, but not so of Pluto\u2019s small moons. These small satellites are spinning much faster, with Hydra \u2013 the most distant moon – rotating an unprecedented 89 times during a single lap around Pluto. Scientists believe these spin rates could be chaotic (i.e., variable) because Charon exerts a strong torque that prevents each small moon from settling down into synchronous rotation, which means keeping one face toward the planet.<\/p>\n