{"617156":{"#nid":"617156","#data":{"type":"news","title":"Evidence of Contact with Europa Plume Uncovered in Old Spacecraft Data","body":[{"value":"\u003Cp\u003EGeorgia Tech researchers have uncovered a spacecraft\u0026#39;s close encounter with Jupiter\u0026rsquo;s moon Europa. Evidence had been lurking in data obtained 19 years ago by the\u0026nbsp;spacecraft.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThrough remote observations, researchers have discovered plumes of water vapor shooting off the surface of Jupiter\u0026rsquo;s moon Europa. These plumes, more than 200 meters high, are reminiscent of the geysers in Yellowstone Park.\u003C\/p\u003E\r\n\r\n\u003Cp\u003ELike Earth, the giant planet Jupiter has a strong internal magnetic field. Indeed, if it were visible to the naked eye, the region of space dominated by this magnetic field \u0026ndash; called the magnetosphere of Jupiter \u0026ndash; would be the largest object in our solar system. That\u0026rsquo;s according to \u003Ca href=\u0022https:\/\/www.eas.gatech.edu\/people\/simon-dr-sven\u0022\u003ESven Simon\u003C\/a\u003E, an associate professor in the School of Earth and Atmospheric Sciences (EAS).\u003C\/p\u003E\r\n\r\n\u003Cp\u003EData collected directly by spacecraft indicate that the plumes locally deform Jupiter\u0026rsquo;s magnetic field near Europa and cause a change in the planet\u0026rsquo;s magnetospheric plasma flow around the Europa. A water vapor plume at Europa leaves a characteristic \u0026ldquo;signature\u0026rdquo; in Jupiter\u0026rsquo;s magnetic field, which can be identified in data from a spacecraft, Simon says.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EMeasurements by spacecraft are limited, however, says \u003Ca href=\u0022https:\/\/cos.gatech.edu\/graduates\/fall-2018-liuzzo\u0022\u003ELucas Liuzzo\u003C\/a\u003E, a postdoctoral researcher working with Simon. A spacecraft can measure the magnetic field only along its one-dimensional trajectory, but the interaction between the plumes and their environment is complex and three-dimensional. Therefore, scientists use simulation models to place one-dimensional observations in the context of a three-dimensional interaction.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThis approach is used by Simon\u0026rsquo;s group at EAS, called \u003Ca href=\u0022http:\/\/pwp.gatech.edu\/svensimon\/\u0022\u003EMOSS (Magnetospheres in the Outer Solar System)\u003C\/a\u003E. Recently, the effort revealed a previously unrecognized encounter between a plume from Europa and a spacecraft almost 20 years ago. The accepted paper was posted Jan. 31, 2019, in\u0026nbsp;\u003Ca href=\u0022https:\/\/agupubs.onlinelibrary.wiley.com\/doi\/10.1029\/2018GL081544\u0022\u003EGeophysical Research Letters\u003C\/a\u003E.\u0026nbsp; The work received financial support from NASA.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EIn 1989, NASA launched the spacecraft Galileo to study the moons of Jupiter, including Europa. Between 1996 and 2000, Galileo made several close flybys of Europa. On Jan. 3, 2000, the spacecraft completed its final Europa flyby, dubbed E26.\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003EFast forward to 2018. For his Ph.D. project, second-year graduate student \u003Ca href=\u0022https:\/\/www.eas.gatech.edu\/people\/arnold-hannes\u0022\u003EHannes Arnold\u003C\/a\u003E developed a simulation model of the interaction between Jupiter\u0026rsquo;s magnetospheric plasma and a possible water vapor plume at Europa. Using this model, Arnold analyzed magnetic field data gathered by Galileo.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThe analysis identified signatures that could not be explained solely by the interaction of Jupiter\u0026rsquo;s magnetic field with Europa, Arnold says. \u0026ldquo;In recent years, we have learned that a plume could potentially be \u0026lsquo;visible\u0026rsquo; in the magnetic field near Europa,\u0026rdquo; he adds. \u0026ldquo;Including a plume in our model was our best guess, but still a shot in the dark.\u0026rdquo;\u003C\/p\u003E\r\n\r\n\u003Cp\u003ETo identify the origin of these peculiar signatures, Arnold carried out more than 250 simulations of Europa\u0026rsquo;s plasma environment during Galileo\u0026rsquo;s final flyby, E26. He arrived at a groundbreaking conclusion: the magnetic field data from this flyby almost 20 years ago contain\u003Cs\u003Es \u003C\/s\u003Eunambiguous evidence of Galileo\u0026rsquo;s passage through a plume of water vapor, emanating near a distinct fracture line on Europa\u0026rsquo;s surface.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThe intense outgassing from the plume locally pushes Jupiter\u0026rsquo;s magnetic field away from Europa, generating a distinct bulge in the magnetic pattern observed by Galileo, Liuzzo says.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EOther scientists have modeled the magnetic field signatures from E26, Simon says, but \u0026ldquo;all of them had overlooked this important feature in the Galileo data.\u0026rdquo;\u003C\/p\u003E\r\n\r\n\u003Cp\u003EIn combination with a \u003Ca href=\u0022https:\/\/www.nature.com\/articles\/s41550-018-0450-z\u0022\u003E2018 study\u003C\/a\u003E from University of Michigan researchers, the results \u0026ldquo;provide compelling evidence of persistent plume activity at Europa during the Galileo era,\u0026rdquo; Arnold says.\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026ldquo;They have immediate relevance for the planning of synergistic measurements during upcoming missions that aim to further characterize plume activity at Europa through in-situ observations.\u0026rdquo;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EFigure Caption\u003C\/strong\u003E\u003Cbr \/\u003E\r\nGeometry of the Galileo E26 flyby of Europa as seen (a) from the upstream, Jupiter-averted side and (b) when looking from the Europa\u0026rsquo;s southern hemisphere. The white line denotes the spacecraft\u0026rsquo;s trajectory. (Courtesy Geophysical Research Letters)\u003C\/p\u003E\r\n","summary":null,"format":"limited_html"}],"field_subtitle":[{"value":"Spacecraft Galileo passed through a plume of water vapor during flyby in 2000, study shows"}],"field_summary":[{"value":"\u003Cp\u003EGeorgia Tech researchers uncovered\u0026nbsp;a previously unrecognized encounter between a plume from Jupiter\u0026#39;s moon Europa and the\u0026nbsp;spacecraft Galileo almost 20 years ago.\u003C\/p\u003E\r\n","format":"limited_html"}],"field_summary_sentence":[{"value":"Spacecraft Galileo passed through a plume of water vapor during flyby in 2000, study shows."}],"uid":"30678","created_gmt":"2019-02-01 16:56:59","changed_gmt":"2019-02-01 18:34:16","author":"A. Maureen Rouhi","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2019-02-01T00:00:00-05:00","iso_date":"2019-02-01T00:00:00-05:00","tz":"America\/New_York"},"extras":[],"hg_media":{"617157":{"id":"617157","type":"image","title":"Galileo\u0027s close encounter with a Europa water plume","body":null,"created":"1549040348","gmt_created":"2019-02-01 16:59:08","changed":"1549040348","gmt_changed":"2019-02-01 16:59:08","alt":"","file":{"fid":"234884","name":"2019 Sven Simon Europa plume.6x3.png","image_path":"\/sites\/default\/files\/images\/2019%20Sven%20Simon%20Europa%20plume.6x3.png","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/images\/2019%20Sven%20Simon%20Europa%20plume.6x3.png","mime":"image\/png","size":196038,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/2019%20Sven%20Simon%20Europa%20plume.6x3.png?itok=UWe5VwFh"}},"617159":{"id":"617159","type":"image","title":"Lucas Liuzzo, Hannes Arnold, and Sven Simon","body":null,"created":"1549041352","gmt_created":"2019-02-01 17:15:52","changed":"1549041352","gmt_changed":"2019-02-01 17:15:52","alt":"","file":{"fid":"234885","name":"2019 Sven Simon liuzzo_arnold_simon.4x3jpg.jpg","image_path":"\/sites\/default\/files\/images\/2019%20Sven%20Simon%20liuzzo_arnold_simon.4x3jpg.jpg","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/images\/2019%20Sven%20Simon%20liuzzo_arnold_simon.4x3jpg.jpg","mime":"image\/jpeg","size":301497,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/2019%20Sven%20Simon%20liuzzo_arnold_simon.4x3jpg.jpg?itok=U1WfTIT1"}}},"media_ids":["617157","617159"],"groups":[{"id":"1278","name":"College of Sciences"},{"id":"364801","name":"School of Earth and Atmospheric Sciences (EAS)"}],"categories":[{"id":"136","name":"Aerospace"}],"keywords":[{"id":"81281","name":"Europa"},{"id":"5257","name":"Galileo"},{"id":"174766","name":"Magnetosphere"},{"id":"180365","name":"water plume"},{"id":"180363","name":"Sven Simon"},{"id":"166926","name":"School of Earth and Atmospheric Sciences"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EA. Maureen Rouhi, Ph.D.\u003Cbr \/\u003E\r\nDirector of Communications\u003Cbr \/\u003E\r\nCollege of Sciences\u003C\/p\u003E\r\n","format":"limited_html"}],"email":["maureen.rouhi@cos.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}