{"id":16510,"date":"2015-03-02T22:29:38","date_gmt":"2015-03-02T14:29:38","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/nasa-probe-closes-in-on-dwarf-planet-ceres\/"},"modified":"2015-03-02T22:29:38","modified_gmt":"2015-03-02T14:29:38","slug":"nasa-probe-closes-in-on-dwarf-planet-ceres","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/nasa-probe-closes-in-on-dwarf-planet-ceres\/","title":{"rendered":"NASA probe closes in on dwarf planet Ceres"},"content":{"rendered":"<p>STORY WRITTEN FOR&nbsp;CBS NEWS \u201cSPACE PLACE\u201d&nbsp;&amp; USED WITH PERMISSION<\/p>\n<figure id=\"attachment_4462\" aria-describedby=\"caption-attachment-4462\" style=\"width: 620px\" class=\"wp-caption alignnone\"><img fetchpriority=\"high\" decoding=\"async\" class=\" wp-image-4462\" src=\"http:\/\/spaceflightnow.com\/wp-content\/uploads\/2015\/03\/dawn_approach_ceres.png\" alt=\"Artist's concept of the Dawn spacecraft on approach to Ceres. Credit: NASA\/JPL-Caltech\" width=\"620\" height=\"370\" srcset=\"https:\/\/spaceflightnow.com\/wp-content\/uploads\/2015\/03\/dawn_approach_ceres.png 1191w, https:\/\/spaceflightnow.com\/wp-content\/uploads\/2015\/03\/dawn_approach_ceres-300x179.png 300w, https:\/\/spaceflightnow.com\/wp-content\/uploads\/2015\/03\/dawn_approach_ceres-768x458.png 768w, https:\/\/spaceflightnow.com\/wp-content\/uploads\/2015\/03\/dawn_approach_ceres-1024x611.png 1024w\" sizes=\"(max-width: 620px) 100vw, 620px\"><figcaption id=\"caption-attachment-4462\" class=\"wp-caption-text\">Artist\u2019s concept of the Dawn spacecraft on approach to Ceres. Credit: NASA\/JPL-Caltech<\/figcaption><\/figure>\n<p>NASA\u2019s Dawn spacecraft is closing in on the dwarf planet Ceres, the largest body in the asteroid belt between Mars and Jupiter, beaming back increasingly sharp pictures revealing a heavily cratered world with unexpected \u2014 and so far, mystifying \u2014 spots of light that may be reflections off exposed ice or some other material.<\/p>\n<p>Whatever they are, the surprising spots have generated widespread interest among scientists and non scientists alike as Dawn completes its rendezvous and slips into orbit around Ceres early Friday, three years and more than 900 million miles after wrapping up a year-long study of the rocky asteroid Vesta.<\/p>\n<p>\u201cSuffice it to say, these spots were extremely surprising to the team, and they have been puzzling to everybody who\u2019s seen them,\u201d Carol Raymond, Dawn deputy principal investigator, told reporters Monday. \u201cThe team is really, really exited about this feature because it is unique in the solar system.\u201d<\/p>\n<p>A movie made up of recent Dawn images shows Ceres rotating through a complete 9.1-hour \u201cday.\u201d The bright spots stop shining when they rotate into darkness, indicating they are, in fact, reflected sunlight, possibly from exposed ice or salt deposits.<\/p>\n<p>The presumed deposits may have been uncovered by a recent impact or possibly the result of some much less probable mechanism like ultra-low temperature \u201ccryovolcanism.\u201d But for now, no one knows. And given their unusual brightness, interest is high.<\/p>\n<p>\u201cWe will be revealing its true nature as we get closer and closer to the surface,\u201d Raymond said. \u201cSo the mystery will be solved, but it is one that\u2019s got us on the edge of our seats.\u201d<\/p>\n<p>And one that will require a bit more patience. Dawn is approaching Ceres from its dark side and it will take several more weeks to get into a position to study the bright spots in more detail as the spacecraft spirals inward, eventually reaching a 235-mile-high mapping orbit in December.<\/p>\n<p>The $473 million project is \u201cone of the coolest missions to one of the last unexplored worlds in the solar system,\u201d said Robert Mase, the Dawn project manager at the Jet Propulsion Laboratory in Pasadena, Calif.<\/p>\n<p>Dawn is the first spacecraft to orbit more than one body, the first to visit a dwarf planet \u2014 Ceres \u2014 and the first operational science probe to rely on ion propulsion, using solar-generated electricity to accelerate xenon ions to enormous velocities, producing a gentle but almost continuous thrust.<\/p>\n<p>\u201cWe go from zero to 60 in about four days,\u201d Mase said. \u201cHowever, ion engines are about 10 times more efficient than conventional chemical systems, and we can continue to thrust and accelerate for days and weeks and months or, as Dawn has now for more than five years, to generate tremendous velocities.\u201d<\/p>\n<p>Ceres was discovered in 1801 by the Italian astronomer Giuseppe Piazzi. It was the first asteroid ever discovered and it is the largest in the asteroid belt, a roughly spherical body measuring 606 by 565 miles.<\/p>\n<p>\u201cOne of the first things you notice is how round Ceres is,\u201d Raymond said. \u201cAnd Ceres\u2019 roundness is one of its planetary characteristics. We also know that Ceres is much lighter than the rocky planets and so we know it retained a lot of water and light volatile elements that were present in the solar nebula when Ceres was formed.<\/p>\n<p><iframe loading=\"lazy\" width=\"678\" height=\"381\" src=\"https:\/\/www.youtube.com\/embed\/LP2zbGFXyk0?feature=oembed\" frameborder=\"0\" allowfullscreen=\"\"><\/iframe><\/p>\n<p>In contrast, bodies like the moon and Vesta suffered melting from major impacts that caused the water and other light elements to boil away, \u201cleaving them dry and rocky,\u201d Raymond said.<\/p>\n<p>\u201cOne of the prime motivations of the Dawn mission is to examine these building blocks of the planets, Vesta and Ceres, which are two intact proto-planets from the very dawn of the solar system,\u201d she said. \u201cThey\u2019re literally fossils that we can investigate to really understand the processes that were going on at that time.\u201d<\/p>\n<p>The initial views of Ceres have revealed remarkably smooth areas, chaotic fracture zones and craters of all sizes, she said. The terrain likely holds clues about the dwarf planet\u2019s internal structure and whether a layer of ice exists that might be a remnant of a now frozen sub-surface ocean.<\/p>\n<p>\u201cWe know that Ceres retained a lot of volatiles and its shape is consistent with a differentiation into a rocky core and an ice mantle,\u201d Raymond said. Given heating from radioactive compounds, \u201cit\u2019s inevitable that that ice would have existed as an ocean at some time in the past.<\/p>\n<p>\u201cSo, we do expect that in the past there was ocean in contact with the rock beneath an ice cap and that at present it\u2019s an ice layer that\u2019s beneath a crust of infalls and dust and clays and deposits from sublimation.\u201d<\/p>\n<p>Last year, a European spacecraft studying Ceres from afar detect traces of water vapor in specific longitudinal zones. Raymond said the bright spots are in one of those zones \u201cso it might be related to that water vapor emission.\u201d<\/p>\n<p>\u201cIt\u2019s association with the impact crater may indicate that impact heating resulted in exposure of underlying ice, it\u2019s vaporization, and perhaps we\u2019re seeing a deposit that was left behind, which is rich in material like salts,\u201d she said.<\/p>\n<p>Dawn is equipped with redundant multi-filter cameras sensitive to visible and near infrared light, a gamma ray and neutron detector that can characterize the elemental makeup of the upper few feet of the crust and a visible and infrared mapping spectrometer to study the mineralogy of the dwarf planet.<\/p>\n<p>If all goes well, Dawn will reach its science mapping orbit in December and complete its primary mission in June 2016. A few months later, supplies of hydrazine maneuvering fuel, used to aim the spacecraft and its instruments at Ceres and to reorient the probe to transmit data back to Earth, are expected to run out and Dawn\u2019s mission will come to an end.<\/p>\n<p>\u201cDawn will get down to its lowest orbit, and the plan is for the spacecraft to stay there indefinitely,\u201d Mase said. \u201cThat\u2019s where the mission would end. The orbit is designed such that it\u2019s stable for a very long period of time, so Dawn will actually stay in that orbit for \u2026hundreds of years.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"<p>STORY WRITTEN FOR&nbsp;CBS NEWS \u201cSPACE PLACE\u201d&nbsp;&amp; USED WITH PERMISSION Artist\u2019s concept of the Dawn spacecraft on approach to Ceres. Credit: NASA\/JPL-Caltech NASA\u2019s Dawn spacecraft is closing in on the dwarf planet Ceres, the largest body in the asteroid belt between Mars and Jupiter, beaming back increasingly sharp pictures revealing a heavily cratered world with unexpected [&hellip;]<\/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":[2838,2839],"class_list":["post-16510","post","type-post","status-publish","format-standard","hentry","category-news","tag-ceres","tag-dawn"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/16510"}],"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=16510"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/16510\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=16510"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=16510"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=16510"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}