{"id":14587,"date":"2017-05-26T19:12:01","date_gmt":"2017-05-26T11:12:01","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/jupiter-surprises-in-first-trove-of-data-from-nasas-juno-mission\/"},"modified":"2017-05-26T19:12:01","modified_gmt":"2017-05-26T11:12:01","slug":"jupiter-surprises-in-first-trove-of-data-from-nasas-juno-mission","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/jupiter-surprises-in-first-trove-of-data-from-nasas-juno-mission\/","title":{"rendered":"Jupiter surprises in first trove of data from NASA\u2019s Juno mission"},"content":{"rendered":"
\"\"
This image shows Jupiter\u2019s south pole, as seen by NASA\u2019s Juno spacecraft from an altitude of 32,000 miles (52,000 kilometers). Image credit: NASA\/JPL-Caltech\/SwRI\/MSSS\/Betsy Asher Hall\/Gervasio Robles<\/figcaption><\/figure>\n

The first months of observations of the solar system\u2019s biggest planet from NASA\u2019s Juno spacecraft have revealed huge swirling polar cyclones, previously-undetected structures and motions beneath Jupiter\u2019s distinctive clouds, and the first evidence for what lies at the core of the gas giant, scientists said Thursday.<\/p>\n

There was plenty scientists did not know about the planet when the Juno spacecraft left Earth in 2011, and the probe has sought answers to questions about Jupiter\u2019s interior, magnetic field, auroras and radiation belts, and used a visible light camera to capture the first direct views of the poles.<\/p>\n

\u201cThe general theme of our discoveries is really how different Jupiter looks from what we expected,\u201d said Scott Bolton, Juno\u2019s principal investigator at the Southwest Research Institute in San Antonio. \u201cJuno, in many ways, is looking inside Jupiter for the first time, close-up and personal.\u201d<\/p>\n

Since Juno arrived at its destination July 4, 2016, to wrap up a five-year interplanetary trip, the spacecraft, built and operated by Lockheed Martin, has circled Jupiter six times in an oval-shaped loop that extends a few million miles at its farthest point. Each lap takes more than 53 days, and Juno speedily skirts within 3,000 miles (5,000 kilometers) Jupiter\u2019s cloud tops at closest approach.<\/p>\n

Juno\u2019s science instruments collect most of their data when the orbiter is near Jupiter, taking pictures, measuring plasma and electrons, and probing deep inside the planet to find out what is hidden under its cloudy veneer.<\/p>\n

Many scientists thought Jupiter was \u201crelatively boring and uniform\u201d inside before Juno arrived, Bolton said.<\/p>\n

\u201cFor decades, scientists have assumed this, that if we drop below the cloud tops, below where the sunlight reaches, that pretty much Jupiter was all uniform inside, and it really didn\u2019t matter where you looked, it would all look the same,\u201d Bolton said Thursday. \u201cAnd what we\u2019re finding is anything but that is the truth. It\u2019s very different and very complex.\u201d<\/p>\n

Juno\u2019s microwave radiometer, an instrument similar to those aboard climate satellites looking down on Earth, gathers sounding measurements to peer below the red-orange tapestry of Jupiter\u2019s cloud tops.<\/p>\n

The radiometer is tuned to six wavelengths, detecting thermal radiation emitted from different layers of the atmosphere from the storm clouds and jet streams to as deep as 300 miles, or about 500 kilometers.<\/p>\n

Going into Juno\u2019s mission, scientists anticipated Jupiter\u2019s atmosphere to be relatively consistent deeper than 60 miles, or 100 kilometers. Instead, Juno\u2019s microwave radiometer discovered a belt of ammonia around Jupiter\u2019s equator, and variations in ammonia abundances at other latitudes extending deep into the planet\u2019s atmosphere.<\/p>\n

\u201cThis was completely unexpected,\u201d Bolton said. \u201cYou have a deep band of ammonia that goes from the top of Jupiter as deep as we can see. It goes down to 350 kilometers (217 miles) because that\u2019s the limit of where we\u2019re looking.\u201d<\/p>\n

The ammonia band may penetrate even deeper inside Jupiter, Bolton said.<\/p>\n

\"\"
NASA\u2019s Juno spacecraft carries an instrument called the Microwave Radiometer, which examines Jupiter\u2019s atmosphere beneath the planet\u2019s cloud tops. The data presented at right show abundances of ammonia deep in Jupiter\u2019s atmosphere, with red representing high concentrations and blue representing low concentrations. Credit: NASA\/JPL-Caltech\/SwRI<\/figcaption><\/figure>\n

\u201cWhat this is telling us is that Jupiter is not very well-mixed,\u201d Bolton said. \u201cIt\u2019s not all uniform inside. The idea of, once you drop below the sunlight, that everything would all be uniform, boring and mixed up was completely wrong. It\u2019s actually very different depending on where you look.\u201d<\/p>\n

The findings suggest more ammonia farther down in Jupiter\u2019s atmosphere, and the ammonia detections appear to have no relationship with the zones and belts of clouds visible in pictures from space.<\/p>\n

\u201cThat\u2019s really going to force us to rethink not only how Jupiter works, but how do we explore Saturn, Uranus and Neptune if they are highly variable like this?\u201d Bolton said.<\/p>\n

Other parts of Juno\u2019s scientific sensor suite are mapping Jupiter\u2019s gravity field to learn about the heart of the planet.<\/p>\n

\u201cWhen we went to go measure the gravity field, what we were really looking for was the core \u2014 whether there was a compact core or no core,\u201d Bolton said. \u201cInstead, what we found was that it really looks fuzzy. There may be a core there, but it\u2019s very big, and it may be partially dissolved. We\u2019re studying that, but that came as a big surprise to us that there was no core.\u201d<\/p>\n

Theories about Jupiter\u2019s core before Juno arrived predominately predicted the planet either had a small, dense rocky core between one and 10 times as massive as Earth, or no core at all, scientists said.<\/p>\n

\u201cMost scientists were in one camp or the other, and what we found was really neither was true,\u201d Bolton said. \u201cThere may be a little bit of a compact core, but there may be layers there, and there seems to be a fuzzy core that may be much larger than anybody had anticipated.<\/p>\n

\u201cThe gravity data that we\u2019ve gotten thus far is not really consistent with just a small compact core or zero core, but it is somewhat consistent with a large fuzzy core that may be partially dissolved,\u201d Bolton said. \u201cIt\u2019s also consistent, maybe, with some deep motions, or zonal winds and things like that \u2026 dictating the interior of Jupiter\u2019s dynamics, which are very different than historically models have assumed.\u201d<\/p>\n

Jupiter\u2019s intense magnetic field, the strongest of any planet in the solar system, has also been interrogated by Juno, which has a magnetometer mounted at the end of one of the craft\u2019s three solar array wings.<\/p>\n

\"\"
NASA\u2019s Juno spacecraft is investigating the structure and convection of Jupiter\u2019s interior by reaching through the meteorological layer, the top layer of the planet\u2019s atmosphere. A possible inner \u201crock\u201d core is shown, surrounded by a metallic hydrogen envelope (shown in blue) and outer envelope of molecular hydrogen (shown in brown), all hidden beneath the visible cloud deck. Juno\u2019s gravity field data will reveal new clues about Jupiter\u2019s core. Credit: NASA\/JPL-Caltech\/SwRI<\/figcaption><\/figure>\n

Jack Connerney, Juno\u2019s deputy principal investigator at NASA\u2019s Goddard Space Flight Center in Maryland, described the magnetometer as like a \u201cfancy compass\u201d that can measure the direction and strength of Jupiter\u2019s magnetic field.<\/p>\n

Juno has come closer to Jupiter than any mission before, and proximity yields better magnetic field measurements, Connerney said.<\/p>\n

\u201cWhat we found in our first few passes is that the magnetic field was both stronger than we expected where we expected it to be strong, and it was weaker than we expected where we expected it to be weak,\u201d Connerney said. \u201cIn other words, it evidenced a dramatic spatial variation that we were not quite aware of previously.\u201d<\/p>\n

The fluctuations detected by Juno suggest the spacecraft is unexpectedly close to the magnetic field\u2019s source, or dynamo.<\/p>\n

Scientists thought the magnetic field might be generated in a global pool of liquid metallic hydrogen in Jupiter\u2019s middle layer somewhere between the center of the planet and the atmosphere. Squeezed at extreme pressure, the deep layer of hydrogen is liquified and conducts electricity.<\/p>\n

The magnetic field expands outward from Jupiter and is blown back by the solar wind like a comet\u2019s tail. The magnetic field bubble, called a magnetosphere, is similar to one around Earth, but Jupiter\u2019s is so immense it would be the size of the full moon in the sky, if it was visible with the naked eye.<\/p>\n

Juno\u2019s observations \u201cmight mean that the dynamo is above that metallic hydrogen region,\u201d Connerney said, perhaps in an envelope of molecular hydrogen.<\/p>\n

An infrared camera and ultraviolet spectrometer aboard the Juno spacecraft have been looking at Jupiter\u2019s powerful polar auroras, producing another set of observations that surprised scientists.<\/p>\n

It turns out some of the auroral light emissions seem to be produced by electrons streaming out of Jupiter\u2019s atmosphere, not by charged particles riding field lines into the planet, as is the case with Earth\u2019s auroras. One of Juno\u2019s instruments, an electron detector, found particles moving upward as the orbiter soared over Jupiter\u2019s south pole.<\/p>\n

According to Connerney, the electrons are probably drawn out of the planet along the same field lines scientists thought would see the particles into Jupiter.<\/p>\n

\u201cAs they\u2019re leaving, they collide with hydrogen molecules and excite ultraviolet emissions,\u201d Connerney said. \u201cIt\u2019s a 180-degree turnabout from the way we were thinking about those emissions prior to the Juno observations.\u201d<\/p>\n

\"\"
Juno\u2019s ultraviolet spectrograph recorded this image of Jupiter\u2019s southern aurora. Credit: NASA\/JPL-Caltech\/SWRI<\/figcaption><\/figure>\n

NASA\u2019s Cassini spacecraft, in the final months of its mission, is now orbiting Saturn on a trajectory similar to Juno\u2019s. Bolton said scientists are eager to compare observations from the two craft to compare the solar system\u2019s two largest planets.<\/p>\n

\u201cCassini doesn\u2019t have the exact same kind of instruments we have, and of course, we\u2019re tuned to do this interior research, but it has a lot of great instruments that can learn a lot about the interior and other things that it can do close-up,\u201d said Bolton, who is also a member of the Cassini science team.<\/p>\n

\u201cWe\u2019re both trying to figure out our data from our own planets at the moment, but eventually we will compare, and of course, that\u2019s the key to scientific advancement \u2014 comparative study,\u201d Bolton said. \u201cSo being able to compare Cassini\u2019s measurements at Saturn and Jupiter\u2019s measurements by Juno, we will really be able to advance our understanding how these giant planets work.\u201d<\/p>\n

Juno\u2019s camera has scanned Jupiter during each pass over the planet\u2019s poles, catching dozens of swirling storms in the act, some the size of Earth.<\/p>\n

The Juno team relies on amateur observers and image processors logged in to the mission\u2019s website to crunch raw views from JunoCam and create colorful mosaics.<\/p>\n

\u201cWhat you see are incredible, complex features,\u201d Bolton said. \u201cThese cyclones and anticyclones all over the poles. That wasn\u2019t really expected.<\/p>\n

\u201cThe bluish hue is probably real,\u201d he said of one south pole mosaic. \u201cAnd the biggest feature is that Jupiter, from the poles, doesn\u2019t look anything like it does from the equator.<\/p>\n

\u201cOur usual picture of Jupiter has zones and belts, the Great Red Spot, and you see these stripes, and that\u2019s the Jupiter we\u2019ve all known and grown to love,\u201d Bolton said. \u201cWhen you look from the pole, it looks totally different. If you looked at this picture, and somebody had shown it to you a few years ago, I don\u2019t think anybody would have guessed this is Jupiter.\u201d<\/p>\n

Mission managers tacked on the JunoCam imager to the spacecraft\u2019s instrument package after NASA selected Juno for development in 2005. JunoCam was not originally part of the Juno mission, but officials added the camera as a public outreach tool.<\/p>\n

Scientists said JunoCam\u2019s imagery adds context to their data analysis work, but it also engages a broader community of professional and amateur scientists, space enthusiasts and artists.<\/p>\n

\"\"
Small bright clouds dot Jupiter\u2019s entire south tropical zone in this image acquired by JunoCam on NASA\u2019s Juno spacecraft on May 19, 2017, at an altitude of 7,990 miles (12,858 kilometers). Image credit: NASA\/SWRI\/MSSS\/Gerald Eichstadt\/Sean Doran<\/figcaption><\/figure>\n

\u201cThe contributions of the amateurs are essential,\u201d said Candy Hansen, Juno co-investigator at the Planetary Science Institute in Tucson, Arizona. \u201cI cannot understate how important the contributions are. We don\u2019t have a way to plan our data without the contributions of the amateur astronomers.<\/p>\n

\u201cWe don\u2019t have a big image processing team, so we are completely relying on the help of our citizen scientists,\u201d Hansen said.<\/p>\n

JunoCam collects images in strips as the spacecraft spins on its main axis, and contributors stitch the strips together to make pictures.<\/p>\n

\u201cWhat I find the most phenomenal of all is that this takes real work,\u201d Hansen said. \u201cWhen you download a JunoCam image and process it, it\u2019s not something you do in five minutes. The pictures that we get that people upload back onto our site, they\u2019ve invested hours and hours of their own time, and then generously returned that to us.\u201d<\/p>\n

Hansen said JunoCam has spotted \u201ctiny\u201d features suspended above Jupiter\u2019s main cloud deck that look like squall lines on Earth. The clouds are dwarfed by Jupiter\u2019s enormous scale, but they actually stretch around 30 miles, or 50 kilometers, across, she said.<\/p>\n

\u201cI keep saying (they\u2019re tiny), but they\u2019re really not tiny at all,\u201d Hansen said. \u201cThey\u2019re up above the cloud deck at a pressure level where the temperature is going to be very cold, so what you\u2019re seeing is most likely ice crystals of water ice and ammonia ice.\u201d<\/p>\n

Juno\u2019s next close-up encounter with Jupiter is set for July 11, when the orbiter will pass above the Great Red Spot for the first time.<\/p>\n

The discoveries made by Juno so far are \u201cmaking us rethink how giant planets work, not just in our own solar system, but giant planets are really important throughout the galaxy and the universe,\u201d Bolton said.<\/p>\n

\u201cWe\u2019re getting the first really close-up and personal look at Jupiter, and we\u2019re seeing that a lot of our ideas were incorrect, and maybe naive, that it\u2019s very complex, and there are a lot of deep motions going on,\u201d he added.<\/p>\n

NASA decided in February to forego an engine burn to move Juno into a 14-day orbit with a tighter path around Jupiter after engineers detected a problem with check valves inside the craft\u2019s propulsion system last year.<\/p>\n

Juno\u2019s mission will last until at least February 2018, enough time to make 11 science orbits around Jupiter, instead of the 32 laps originally planned. But NASA could extend the mission another three years to give Juno more flybys near Jupiter.<\/p>\n

\u201cThere\u2019s a theme here. There are motions going on just beneath the clouds that we see with the microwaves, and there may be very deep winds and deep motions going on that we see with the gravity field (sensors),\u201d Bolton said. \u201cIt\u2019s hard to say yet, but more data will tell us how deep those really go. We\u2019re just at the beginning of this mission, where eventually we\u2019re going to map out that planet.\u201d<\/p>\n

Email the author.<\/i><\/b><\/p>\n

Follow Stephen Clark on Twitter: @StephenClark1.<\/strong><\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

This image shows Jupiter\u2019s south pole, as seen by NASA\u2019s Juno spacecraft from an altitude of 32,000 miles (52,000 kilometers). Image credit: NASA\/JPL-Caltech\/SwRI\/MSSS\/Betsy Asher Hall\/Gervasio Robles The first months of observations of the solar system\u2019s biggest planet from NASA\u2019s Juno spacecraft have revealed huge swirling polar cyclones, previously-undetected structures and motions beneath Jupiter\u2019s distinctive clouds, […]<\/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":[1183,1929,2522,1606,472,1561],"class_list":["post-14587","post","type-post","status-publish","format-standard","hentry","category-news","tag-jet-propulsion-laboratory","tag-juno","tag-junocam","tag-jupiter","tag-lockheed-martin","tag-planetary-science"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/14587"}],"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=14587"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/14587\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=14587"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=14587"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=14587"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}