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Preparations for Next Moonwalk Simulations Underway (and Underwater)<\/h1>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n![\"The](\"https:\/\/www.nasa.gov\/wp-content\/uploads\/2024\/12\/1-pia26484-io-north-polar-region.png?w=2048\")
<\/a><\/figure>\nThe north polar region of Jupiter\u2019s volcanic moon Io was captured by the JunoCam imager aboard NASA\u2019s Juno during the spacecraft\u2019s 57th close pass of the gas giant on Dec. 30, 2023. A technique called annealing was used to help repair radiation damage to the camera in time to capture this image. <\/div>\nImage data: NASA\/JPL-Caltech\/SwRI\/MSSS Image processing by Gerald Eichst\u00e4dt<\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\nAn experimental technique rescued a camera aboard the agency\u2019s Juno spacecraft, offering lessons that will benefit other space systems that experience high radiation.<\/em><\/p>\nThe mission team of NASA\u2019s Jupiter-orbiting Juno spacecraft executed a deep-space move in December 2023 to repair its JunoCam imager to capture photos of the Jovian moon Io. Results from the long-distance save were presented during a technical session on July 16 at the Institute of Electrical and Electronics Engineers Nuclear & Space Radiation Effects Conference in Nashville.<\/p>\n
JunoCam is a color, visible-light camera. The optical unit for the camera is located outside a titanium-walled radiation vault, which protects sensitive electronic components for many of Juno\u2019s engineering and science instruments.<\/p>\n
This is a challenging location because Juno\u2019s travels carry it through the most intense planetary radiation fields in the solar system. While mission designers were confident JunoCam<\/a> could operate through the first eight orbits of Jupiter, no one knew how long the instrument would last after that. <\/p>\nThroughout Juno\u2019s first 34 orbits (its prime mission), JunoCam operated normally, returning images the team routinely incorporated into the mission\u2019s science papers. Then, during its 47th orbit, the imager began showing hints of radiation damage. By orbit 56, nearly all the images were corrupted. <\/p>\n
\n\n\n![\"The](\"https:\/\/www.nasa.gov\/wp-content\/uploads\/2025\/07\/e1-pia26642-junocam-noise-image.png?w=452\")
<\/a><\/figure>\nThe graininess and horizontal lines seen in this JunoCam image show evidence that the camera aboard NASA\u2019s Juno mission suffered radiation damage. The image, which captures one of the circumpolar cyclones on Jupiter\u2019s north pole, was taken Nov. 22, 2023. <\/div>\nNASA\/JPL-Caltech\/SwRI\/MSSS<\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\nLong Distance Microscopic Repair<\/strong><\/h3>\nWhile the team knew the issue may be tied to radiation, pinpointing what, specifically, was damaged within JunoCam was difficult from hundreds of millions of miles away. Clues pointed to a damaged voltage regulator that is vital to JunoCam\u2019s power supply. With few options for recovery, the team turned to a process called annealing, where a material is heated for a specified period before slowly cooling. Although the process is not well understood, the idea is that the heating can reduce defects in the material.<\/p>\n
\u201cWe knew annealing can sometimes alter a material like silicon at a microscopic level but didn\u2019t know if this would fix the damage,\u201d said JunoCam imaging engineer Jacob Schaffner of Malin Space Science Systems in San Diego, which designed and developed JunoCam and is part of the team that operates it. \u201cWe commanded JunoCam\u2019s one heater to raise the camera\u2019s temperature to 77 degrees Fahrenheit \u2014 much warmer than typical for JunoCam \u2014 and waited with bated breath to see the results.\u201d<\/p>\n
Soon after the annealing process finished, JunoCam began cranking out crisp images for the next several orbits. But Juno was flying deeper and deeper into the heart of Jupiter\u2019s radiation fields with each pass. By orbit 55, the imagery had again begun showing problems.\u00a0<\/p>\n
\u201cAfter orbit 55, our images were full of streaks and noise,\u201d said JunoCam instrument lead Michael Ravine of Malin Space Science Systems. \u201cWe tried different schemes for processing the images to improve the quality, but nothing worked. With the close encounter of Io bearing down on us in a few weeks, it was Hail Mary time: The only thing left we hadn\u2019t tried was to crank JunoCam\u2019s heater all the way up and see if more extreme annealing would save us.\u201d<\/p>\n
Test images sent back to Earth during the annealing showed little improvement the first week. Then, with the close approach of Io only days away, the images began to improve dramatically. By the time Juno came within 930 miles (1,500 kilometers) of the volcanic moon\u2019s surface on Dec. 30, 2023, the images were almost as good as the day the camera launched, capturing detailed views of Io\u2019s north polar region<\/a> that revealed mountain blocks covered in sulfur dioxide frosts rising sharply from the plains and previously uncharted volcanos with extensive flow fields of lava.<\/p>\nTesting Limits<\/strong><\/h3>\nTo date, the solar-powered spacecraft has orbited Jupiter 74 times. Recently, the image noise returned during Juno\u2019s 74th orbit.<\/p>\n
Since first experimenting with JunoCam, the Juno team has applied derivations of this annealing technique on several Juno instruments and engineering subsystems.<\/p>\n
\u201cJuno is teaching us how to create and maintain spacecraft tolerant to radiation, providing insights that will benefit satellites in orbit around Earth,\u201d said Scott Bolton, Juno\u2019s principal investigator from the Southwest Research Institute in San Antonio. \u201cI expect the lessons learned from Juno will be applicable to both defense and commercial satellites as well as other NASA missions.\u201d<\/p>\n
More About Juno<\/strong><\/h3>\nNASA\u2019s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Juno mission for the principal investigator, Scott Bolton, of the Southwest Research Institute in San Antonio. Juno is part of NASA\u2019s New Frontiers Program, which is managed at NASA\u2019s Marshall Space Flight Center in Huntsville, Alabama, for the agency\u2019s Science Mission Directorate in Washington. The Italian Space Agency, Agenzia Spaziale Italiana, funded the Jovian InfraRed Auroral Mapper. Lockheed Martin Space in Denver built and operates the spacecraft. Various other institutions around the U.S. provided several of the other scientific instruments on Juno.<\/p>\n
More information about Juno is at: <\/p>\n
https:\/\/www.nasa.gov\/juno<\/a><\/p>\nNews Media Contact<\/h3>\n
DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011
agle@jpl.nasa.gov<\/a><\/p>\nKaren Fox \/ Molly Wasser
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov<\/a>\u00a0\/\u00a0molly.l.wasser@nasa.gov<\/a><\/p>\nDeb Schmid
Southwest Research Institute, San Antonio
210-522-2254
dschmid@swri.org<\/a><\/p>\n2025-091<\/p>\n
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![\"The](\"https:\/\/www.nasa.gov\/wp-content\/uploads\/2024\/12\/1-pia26484-io-north-polar-region.png\")
<\/a><\/figure>An experimental technique rescued a camera aboard the agency\u2019s Juno spacecraft, offering lessons that will benefit other space systems that experience high radiation.<\/em><\/p>\n The mission team of NASA\u2019s Jupiter-orbiting Juno spacecraft executed a deep-space move in December 2023 to repair its JunoCam imager to capture photos of the Jovian moon Io. Results from the long-distance save were presented during a technical session on July 16 at the Institute of Electrical and Electronics Engineers Nuclear & Space Radiation Effects Conference in Nashville.<\/p>\n JunoCam is a color, visible-light camera. The optical unit for the camera is located outside a titanium-walled radiation vault, which protects sensitive electronic components for many of Juno\u2019s engineering and science instruments.<\/p>\n This is a challenging location because Juno\u2019s travels carry it through the most intense planetary radiation fields in the solar system. While mission designers were confident JunoCam<\/a> could operate through the first eight orbits of Jupiter, no one knew how long the instrument would last after that. <\/p>\n Throughout Juno\u2019s first 34 orbits (its prime mission), JunoCam operated normally, returning images the team routinely incorporated into the mission\u2019s science papers. Then, during its 47th orbit, the imager began showing hints of radiation damage. By orbit 56, nearly all the images were corrupted. <\/p>\n While the team knew the issue may be tied to radiation, pinpointing what, specifically, was damaged within JunoCam was difficult from hundreds of millions of miles away. Clues pointed to a damaged voltage regulator that is vital to JunoCam\u2019s power supply. With few options for recovery, the team turned to a process called annealing, where a material is heated for a specified period before slowly cooling. Although the process is not well understood, the idea is that the heating can reduce defects in the material.<\/p>\n \u201cWe knew annealing can sometimes alter a material like silicon at a microscopic level but didn\u2019t know if this would fix the damage,\u201d said JunoCam imaging engineer Jacob Schaffner of Malin Space Science Systems in San Diego, which designed and developed JunoCam and is part of the team that operates it. \u201cWe commanded JunoCam\u2019s one heater to raise the camera\u2019s temperature to 77 degrees Fahrenheit \u2014 much warmer than typical for JunoCam \u2014 and waited with bated breath to see the results.\u201d<\/p>\n Soon after the annealing process finished, JunoCam began cranking out crisp images for the next several orbits. But Juno was flying deeper and deeper into the heart of Jupiter\u2019s radiation fields with each pass. By orbit 55, the imagery had again begun showing problems.\u00a0<\/p>\n \u201cAfter orbit 55, our images were full of streaks and noise,\u201d said JunoCam instrument lead Michael Ravine of Malin Space Science Systems. \u201cWe tried different schemes for processing the images to improve the quality, but nothing worked. With the close encounter of Io bearing down on us in a few weeks, it was Hail Mary time: The only thing left we hadn\u2019t tried was to crank JunoCam\u2019s heater all the way up and see if more extreme annealing would save us.\u201d<\/p>\n Test images sent back to Earth during the annealing showed little improvement the first week. Then, with the close approach of Io only days away, the images began to improve dramatically. By the time Juno came within 930 miles (1,500 kilometers) of the volcanic moon\u2019s surface on Dec. 30, 2023, the images were almost as good as the day the camera launched, capturing detailed views of Io\u2019s north polar region<\/a> that revealed mountain blocks covered in sulfur dioxide frosts rising sharply from the plains and previously uncharted volcanos with extensive flow fields of lava.<\/p>\n To date, the solar-powered spacecraft has orbited Jupiter 74 times. Recently, the image noise returned during Juno\u2019s 74th orbit.<\/p>\n Since first experimenting with JunoCam, the Juno team has applied derivations of this annealing technique on several Juno instruments and engineering subsystems.<\/p>\n \u201cJuno is teaching us how to create and maintain spacecraft tolerant to radiation, providing insights that will benefit satellites in orbit around Earth,\u201d said Scott Bolton, Juno\u2019s principal investigator from the Southwest Research Institute in San Antonio. \u201cI expect the lessons learned from Juno will be applicable to both defense and commercial satellites as well as other NASA missions.\u201d<\/p>\n NASA\u2019s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Juno mission for the principal investigator, Scott Bolton, of the Southwest Research Institute in San Antonio. Juno is part of NASA\u2019s New Frontiers Program, which is managed at NASA\u2019s Marshall Space Flight Center in Huntsville, Alabama, for the agency\u2019s Science Mission Directorate in Washington. The Italian Space Agency, Agenzia Spaziale Italiana, funded the Jovian InfraRed Auroral Mapper. Lockheed Martin Space in Denver built and operates the spacecraft. Various other institutions around the U.S. provided several of the other scientific instruments on Juno.<\/p>\n More information about Juno is at: <\/p>\n https:\/\/www.nasa.gov\/juno<\/a><\/p>\n DC Agle Karen Fox \/ Molly Wasser Deb Schmid 2025-091<\/p>\n<\/a><\/figure>Long Distance Microscopic Repair<\/strong><\/h3>\n
Testing Limits<\/strong><\/h3>\n
More About Juno<\/strong><\/h3>\n
News Media Contact<\/h3>\n
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011
agle@jpl.nasa.gov<\/a><\/p>\n
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov<\/a>\u00a0\/\u00a0molly.l.wasser@nasa.gov<\/a><\/p>\n
Southwest Research Institute, San Antonio
210-522-2254
dschmid@swri.org<\/a><\/p>\nShare<\/h2>\n<\/p><\/div>\n