{"id":15805,"date":"2016-01-05T19:35:59","date_gmt":"2016-01-05T11:35:59","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/plutos-floating-mountains-intriguing-structures-fascinate-scientists\/"},"modified":"2016-01-05T19:35:59","modified_gmt":"2016-01-05T11:35:59","slug":"plutos-floating-mountains-intriguing-structures-fascinate-scientists","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/plutos-floating-mountains-intriguing-structures-fascinate-scientists\/","title":{"rendered":"Pluto\u2019s floating mountains, intriguing structures fascinate scientists"},"content":{"rendered":"

STORY WRITTEN FOR CBS NEWS & USED WITH PERMISSION<\/p>\n

\"Pluto
Pluto nearly fills the frame in this image from the Long Range Reconnaissance Imager (LORRI) aboard New Horizons, taken on July 13, 2015, when the spacecraft was 476,000 miles (768,000 kilometers) from the surface. This is the last and most detailed image sent to Earth before the spacecraft\u2019s closest approach to Pluto on July 14. The color image has been combined with lower-resolution color information from the Ralph instrument that was acquired earlier on July 13. Credits: NASA\/APL\/SwRI<\/figcaption><\/figure>\n

Nearly six months after NASA\u2019s New Horizons probe zoomed past Pluto, just one quarter of the data stored on board has made its way back to waiting scientists, revealing a surprisingly varied terrain that includes craters, glacial flows in vast, icy plains and steep mountains of frozen water floating in a \u201csea\u201d of slush-like nitrogen ice.<\/p>\n

While New Horizons has answered many of the most outstanding questions about the solar system\u2019s famously demoted outermost \u201cplanet,\u201d the project\u2019s principal investigator said Tuesday the science team expects a steady stream of new discoveries in the months ahead as the spacecraft slowly but surely sends back its treasure trove of stored data.<\/p>\n

\u201cThree quarters of (the recorded data) is still up on the spacecraft, and no one has seen it,\u201d Alan Stern told astronomers at the American Astronomical Society\u2019s winter meeting near Orlando, Fla. \u201cSo we expect to be having presents continue to rain down throughout most of this year, probably into October or November.\u201d<\/p>\n

Launched in January 2006, New Horizons raced past Pluto and its moons on July 14 and is now sailing ever deeper into the Kuiper Belt where uncounted remnants left over from the birth of the solar system orbit in frozen anonymity.<\/p>\n

Now twice as far beyond Pluto as Earth is from the sun, New Horizons has beamed back stunning high-resolution views of the dwarf planet\u2019s hazy, backlit atmosphere and surface, revealing a vast heart-shaped ice plain informally known as Sputnik Planum surrounded by jumbled ice mountains towering as high as the Rockies on Earth.<\/p>\n

\u201cSputnik Planum is a vast ice field \u2026 and is ringed by mountain ranges all the way around,\u201d Stern said. \u201cIt sits about three to four kilometers (2.5 miles) below those mountain ranges and we believe it\u2019s actually a large impact basin.\u201d<\/p>\n

The presumed impact that created that basin would have released an enormous amount of energy, probably increasing the world\u2019s tilt.<\/p>\n

\u201cIt\u2019s so large and its volume is so great that the negative mass anomaly caused by that impact has very likely caused the (tilt) of the planet to shift and to move this object to its current location near the equator of Pluto,\u201d Stern said.<\/p>\n

Before New Horizons reached Pluto, scientists did not known whether they would find steep topography like mountain ranges \u201cbecause nitrogen ice, which is the dominant constituent of Pluto\u2019s surface seen spectroscopically from Earth, is a very weak material even at 40 Kelvin (-387 F),\u201d Stern said.<\/p>\n

\u201cIt has the consistency, or the viscosity, of toothpaste, and if you try and build a mountain out of it, it\u2019ll slump and relax, even in Pluto\u2019s low gravity, over very short time scales.\u201d<\/p>\n

Steep topography \u2014 mountains \u2014 would be evidence that nitrogen ice \u201cwas thin, just a veneer on the surface, and that the constructional material had to be something much stronger,\u201d Stern said. \u201cMost likely water ice, because water ice is the most common constructional material on everything in the outer solar system that\u2019s not a giant planet.\u201d<\/p>\n

Data from New Horizons confirmed the mountains are indeed made of ice, huge blocks of ultra-hard, deeply frozen water ice many miles across. The peaks, many of which feature methane icecaps, have a chaotic appearance and do not resemble coherent mountain ranges, Stern said, which \u201cmay be the result of that large impact that is believed to have created Sputnik Planum.\u201d<\/p>\n

\u201cBut the interesting thing is that water ice actually floats in nitrogen ice, it\u2019s less dense, so it will tend to rise,\u201d he said. \u201cAnd these water ice blocks appear to have been removed from a subsurface layer and \u2026 borne up to the surface where they are now floating in that large nitrogen ice reservoir called Sputnik Planum.\u201d<\/p>\n

The plain itself features strange cell-like structures, or \u201covoids,\u201d that are believed to be the result of thermal convection in the ice. And that convection presumably helps resurface Sputnik Planum.<\/p>\n

\u201cWe have looked and looked and looked and even in high-resolution imaging, we can\u2019t find a single crater on the surface of Sputnik Planum in almost a million square kilometers,\u201d Stern said. \u201cAnd that tells us that (the surface) is very young, and that it\u2019s being continually renewed.\u201d<\/p>\n

That was a major surprise, he added.<\/p>\n

\u201cWe didn\u2019t predict, as planetary scientists, that a small planet like Pluto with a large surface area-to-mass ratio could still be active and would not have completely cooled off after four billion years. And yet it has.\u201d<\/p>\n

Likewise, glacial flows were not expected because none are seen on icy satellites elsewhere in the solar system. But New Horizons has spotted obvious flow patterns where nitrogen ice apparently creeps around obstacles and other areas where ice has \u201cpoured down out of the mountains and pooled into Sputnik Planum,\u201d Stern said. \u201cThat may be the mechanism by which it filled up with nitrogen in the beginning. We\u2019ll see.\u201d<\/p>\n

Also surprising: countless pits across the southern parts of Sputnik Planum that can measure miles across and hundreds of yards deep.<\/p>\n

\"This
This image was taken by the Long Range Reconnaissance Imager (LORRI) on NASA\u2019s New Horizons spacecraft shortly before closest approach to Pluto on July 14, 2015; it resolves details as small as 270 yards (250 meters). The scene shown is about 130 miles (210 kilometers) across. The sun illuminates the scene from the left, and north is to the upper left. Credits: NASA\/JHUAPL\/SwRI<\/figcaption><\/figure>\n

\u201cThey look like bacteria. They are not!\u201d Stern joked. \u201cIn any case, these sublimation pits are essentially ubiquitous across the southern portions of Sputnik Planum. \u2026 Some of the sublimation pits have merged, and it appears that the material beneath the ice is very dark.\u201d<\/p>\n

One working hypothesis, he said, is that everywhere on Pluto the \u201cactual planet\u201d is very dark and all of the regions that are bright are due to ices deposited on the surface by atmospheric transport.<\/p>\n

\u201cIt appears this is confirming that, because we can see through the volatiles down to what appears to be the dark heart of Pluto.\u201d<\/p>\n

New Horizons is on course to fly by another Kuiper Belt body on Jan. 1, 2019.<\/p>\n","protected":false},"excerpt":{"rendered":"

STORY WRITTEN FOR CBS NEWS & USED WITH PERMISSION Pluto nearly fills the frame in this image from the Long Range Reconnaissance Imager (LORRI) aboard New Horizons, taken on July 13, 2015, when the spacecraft was 476,000 miles (768,000 kilometers) from the surface. This is the last and most detailed image sent to Earth before the spacecraft\u2019s […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[2],"tags":[2884,2173,2174,1561,2848],"class_list":["post-15805","post","type-post","status-publish","format-standard","hentry","category-news","tag-alan-stern","tag-kuiper-belt","tag-new-horizons","tag-planetary-science","tag-pluto"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/15805"}],"collection":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/comments?post=15805"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/15805\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=15805"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=15805"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=15805"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}