{"id":11628,"date":"2021-06-08T23:42:09","date_gmt":"2021-06-08T15:42:09","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/jupiters-moon-ganymede-seen-up-close-for-first-time-in-21-years\/"},"modified":"2021-06-08T23:42:09","modified_gmt":"2021-06-08T15:42:09","slug":"jupiters-moon-ganymede-seen-up-close-for-first-time-in-21-years","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/jupiters-moon-ganymede-seen-up-close-for-first-time-in-21-years\/","title":{"rendered":"Jupiter\u2019s moon Ganymede seen up close for first time in 21 years"},"content":{"rendered":"
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This image of Ganymede was obtained by the JunoCam imager during Juno\u2019s June 7, 2021, flyby of the icy moon. Credit: NASA\/JPL-Caltech\/SwRI\/MSSS<\/figcaption><\/figure>\n

NASA\u2019s Juno spacecraft flew by Ganymede, Jupiter\u2019s largest moon, Monday on the first close-up visit to the icy world since 2000.<\/p>\n

The first images from the flyby show Ganymede\u2019s cratered, icy surface in \u201cremarkable detail,\u201d NASA said. The moon is covered in patches of dark and bright terrain, with long, stripe-like grooves and ridges also visible. Scientists say the linear features could be linked to tectonic faults.<\/p>\n

The solar-powered Juno spacecraft\u2019s JunoCam imager and navigation camera took pictures as the orbiter zipped by Ganymede at 1:35 p.m. EDT (1735 GMT) Monday at a distance of about 645 miles (1,038 kilometers).<\/p>\n

\u201cThis is the closest any spacecraft has come to this mammoth moon in a generation,\u201d said Scott Bolton, the Juno mission\u2019s principal investigator from the Southwest Research Institute in San Antonio. \u201cWe are going to take our time before we draw any scientific conclusions, but until then we can simply marvel at this celestial wonder \u2014 the only moon in our solar system bigger than the planet Mercury.\u201d<\/p>\n

During the speedy flyby, Juno passed Ganymede at a speed of more than 40,000 mph, or 19 kilometers per second.<\/p>\n

In addition Juno\u2019s scientific observations, the encounter used Ganymede\u2019s gravity to shrink the period of spacecraft\u2019s oval-shaped orbit around Jupiter from 53 days to 43 days, setting up for a flyby with Europa in September 2022, and flybys with the volcanic moon Io in 2023 and 2024.<\/p>\n

Juno is on an extended mission orbit around Jupiter, where it arrived July 4, 2016, to study the giant planet\u2019s atmosphere, magnetic field, and internal structure. The robotic mission launched Aug. 5, 2011, from Cape Canaveral aboard a United Launch Alliance Atlas 5 rocket.<\/p>\n

The JunoCam instrument\u2019s visible light camera viewed almost an entire side of Ganymede during the flyby Monday. The first views returned to Earth show a black-and-white view of the icy moon, the largest in the solar system and the only moon with its own magnetic field. Future data downlinks allow imaging experts to create a color portrait of Ganymede, according to NASA.<\/p>\n

Juno\u2019s Stellar Reference Unit, part of the spacecraft\u2019s navigation system, captured a view of the night side of Ganymede. The light-sensitive camera resolved the moon\u2019s surface illuminated by dim light scattered off Jupiter.<\/p>\n

NASA said the JunoCam view of Ganymede has a resolution of about 0.6 miles, or 1 kilometer. The high velocity Juno\u2019s encounter with Ganymede meant there was enough time for JunoCam to take five images.<\/p>\n

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This image of the dark side of Ganymede was obtained by Juno\u2019s Stellar Reference Unit navigation camera during its June 7, 2021, flyby of the moon. Credit: NASA\/JPL-Caltech\/SwRI<\/figcaption><\/figure>\n

The navigation camera image resolution is between 0.37 to 0.56 miles (600 to 900 meters) per pixel.<\/p>\n

\u201cThe conditions in which we collected the dark side image of Ganymede were ideal for a low-light camera like our Stellar Reference Unit,\u201d said Heidi Becker, Juno\u2019s radiation monitoring lead at JPL. \u201cSo this is a different part of the surface than seen by JunoCam in direct sunlight. It will be fun to see what the two teams can piece together.\u201d<\/p>\n

Juno\u2019s ultraviolet spectrograph, Jovian infrared auroral mapper, and microwave radiometer were active during the Ganymede flyby to measure the composition, thickness, and temperature of the moon\u2019s water-ice crust. Juno was also tuned to measure the radiation environment around Ganymede, collecting data to benefit future missions to study Jupiter and its moons.<\/p>\n

Bolton said Tuesday that the Juno spacecraft, built by Lockheed Martin, executed the flyby sequence as planned.<\/p>\n

Scientists believe Ganymede harbors an underground saltwater ocean. Evidence gathered during observations of Ganymede\u2019s aurorae with the Hubble Space Telescope showed the light displays \u201crocking\u201d back and forth, revealing insights about the moon\u2019s magnetic field. Scientists can infer assumptions about Ganymede\u2019s interior from the magnetic field measurements.<\/p>\n

A shell of water ice, likely with rock mixed in, covers Ganymede\u2019s buried ocean, which scientists think contains more water than all the water on the surface of Earth.<\/p>\n

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Artist\u2019s concept of the Juno spacecraft at Ganymede. Credit: NASA\/JPL-Caltech<\/figcaption><\/figure>\n

The last mission to explore Jupiter\u2019s moons was Galileo, a NASA spacecraft that orbited Jupiter from 1995 until 2003. Galileo\u2019s last close flyby with Ganymede occurred May 20, 2000.<\/p>\n

NASA\u2019s Voyager 1 and Voyager 2 probes also observed Ganymede and Jupiter\u2019s other large moons during a pair of flybys in 1979.<\/p>\n

Juno\u2019s science team will compare the fresh images of Ganymede with views captured by previous missions. Scientists will look for changes in Ganymede\u2019s surface, such as fresh craters, which could help astronomers better understand the population of objects that impact moons in the outer solar system, according to NASA.<\/p>\n

Juno\u2019s flyby of Ganymede offers a taste of what\u2019s to come with the European Space Agency\u2019s Jupiter Icy Moons Explorer, or JUICE, mission set for launch next year. The robotic JUICE spacecraft will arrive in orbit around Jupiter in 2029, perform flybys of several of Jupiter\u2019s moons, then enter orbit at Ganymede in 2032.<\/p>\n

On Tuesday, Juno completed its 33rd close science pass of Jupiter, reaching the closest point in its elongated orbit around the giant planet.<\/p>\n

Jupiter\u2019s asymmetric gravity field is gradually perturbing Juno\u2019s trajectory and pulling the closest point of the spacecraft\u2019s orbit northward over time. The shift in Juno\u2019s orbit will allow the spacecraft to get a better view of Jupiter\u2019s North Pole, and also enables the flybys of Ganymede, Europa, and Io.<\/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 of Ganymede was obtained by the JunoCam imager during Juno\u2019s June 7, 2021, flyby of the icy moon. Credit: NASA\/JPL-Caltech\/SwRI\/MSSS NASA\u2019s Juno spacecraft flew by Ganymede, Jupiter\u2019s largest moon, Monday on the first close-up visit to the icy world since 2000. The first images from the flyby show Ganymede\u2019s cratered, icy surface in \u201cremarkable […]<\/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":[],"class_list":["post-11628","post","type-post","status-publish","format-standard","hentry","category-news"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/11628"}],"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=11628"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/11628\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=11628"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=11628"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=11628"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}