Jump to content

Danish Instrument Helps NASA’s Juno Spacecraft See Radiation


Recommended Posts

  • Publishers
Posted

Using cameras designed for navigation, scientists count ‘fireflies’ to determine the amount of radiation the spacecraft receives during each orbit of Jupiter.

Scientists with NASA’s Juno mission have developed the first complete 3D radiation map of the Jupiter system. Along with characterizing the intensity of the high-energy particles near the orbit of the icy moon Europa, the map shows how the radiation environment is sculpted by the smaller moons orbiting near Jupiter’s rings.

The work relies on data collected by Juno’s Advanced Stellar Compass (ASC), which was designed and built by the Technical University of Denmark, and the spacecraft’s Stellar Reference Unit (SRU), which was built by Leonardo SpA in Florence, Italy. The two datasets complement each other, helping Juno scientists characterize the radiation environment at different energies.

Both the ASC and SRU are low-light cameras designed to assist with deep-space navigation. These types of instruments are on almost all spacecraft. But to get them to operate as radiation detectors, Juno’s science team had to look at the cameras in a whole new light.

“On Juno we try to innovate new ways to use our sensors to learn about nature, and we have used many of our science instruments in ways they were not designed for,” said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. “This is the first detailed radiation map of the region at these higher energies, which is a major step in understanding how Jupiter’s radiation environment works. This will help planning observations for the next generation of missions to the Jovian system.”

Counting Fireflies

Consisting of four star cameras on the spacecraft’s magnetometer boom, Juno’s ASC takes images of stars to determine the spacecraft’s orientation in space, which is vital to the success of the mission’s magnetic field experiment. But the instrument has also proved to be a valuable detector of high-energy particle fluxes in Jupiter’s magnetosphere. The cameras record “hard radiation,” or ionizing radiation that impacts a spacecraft with sufficient energy to pass through the ASC’s shielding.

“Every quarter-second, the ASC takes an image of the stars,” said Juno scientist John Leif Jørgensen of the Technical University of Denmark. “Very energetic electrons that penetrate its shielding leave a telltale signature in our images that looks like the trail of a firefly. The instrument is programmed to count the number of these fireflies, giving us an accurate calculation of the amount of radiation.”

pia26331.jpg?w=1648
Jupiter’s moon Europa was captured by the JunoCam instrument aboard NASA’s Juno spacecraft during the mission’s close flyby on Sept. 29, 2022.
Image data: NASA/JPL-Caltech/SwRI/MSSS. Image processing: Björn Jónsson (CC BY 3.0)

Because of Juno’s ever-changing orbit, the spacecraft has traversed practically all regions of space near Jupiter.

ASC data suggests that there is more very high-energy radiation relative to lower-energy radiation near Europa’s orbit than previously thought. The data also confirms that there are more high-energy electrons on the side of Europa facing its orbital direction of motion than on the moon’s trailing side. This is because most of the electrons in Jupiter’s magnetosphere overtake Europa from behind due to the planet’s rotation, whereas the very high-energy electrons drift backward, almost like fish swimming upstream, and slam into Europa’s front side.

Jovian radiation data is not the ASC’s first scientific contribution to the mission. Even before arriving at Jupiter, ASC data was used to determine a measurement of interstellar dust impacting Juno. The imager also discovered a previously uncharted comet using the same dust-detection technique, distinguishing small bits of the spacecraft ejected by microscopic dust impacting Juno at a high velocity.

Dust Rings

Like Juno’s ASC, the SRU has been used as a radiation detector and a low-light imager. Data from both instruments indicates that, like Europa, the small “shepherd moons” that orbit within or close to the edge of Jupiter’s rings (and help to hold the shape of the rings) also appear to interact with the planet’s radiation environment. When the spacecraft flies on magnetic field lines connected to ring moons or dense dust, the radiation count on both the ASC and SRU drops precipitously. The SRU is also collecting rare low-light images of the rings from Juno’s unique vantage point.

“There is still a lot of mystery about how Jupiter’s rings were formed, and very few images have been collected by prior spacecraft,” said Heidi Becker, lead co-investigator for the SRU and a scientist at NASA’s Jet Propulsion Laboratory in Southern California, which manages the mission. “Sometimes we’re lucky and one of the small shepherd moons can be captured in the shot. These images allow us to learn more precisely where the ring moons are currently located and see the distribution of dust relative to their distance from Jupiter.”

More About the Mission

NASA’s 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’s New Frontiers Program, which is managed at NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate in Washington. The Technical University of Denmark designed and built the Advanced Stellar Compass. The Stellar Reference Unit was built by Leonardo SpA in Florence, Italy. Lockheed Martin Space in Denver built and operates the spacecraft.

More information about Juno is available at:

https://www.nasa.gov/juno

News Media Contacts

DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011
agle@jpl.nasa.gov

Karen Fox / Alana Johnson
NASA Headquarters, Washington
202-385-1600
karen.c.fox@nasa.gov / alana.r.johnson@nasa.gov

Simon Koefoed Toft
Technical University of Denmark, Copenhagen
+45 9137 0088 
sito@dtu.dk

Deb Schmid
Southwest Research Institute, San Antonio
210-522-2254
dschmid@swri.org

2024-111

View the full article

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Similar Topics

    • By NASA
      Credit: NASA NASA’s Small Spacecraft Systems Virtual Institute (S3VI) is pleased to announce the official release of the highly anticipated 2024 State-of-the-Art Small Spacecraft Technology report. This significant accomplishment was made possible by the contributions of numerous dedicated people across NASA who graciously supported the preparation of the document as authors and reviewers. We also want to extend our gratitude to all the companies, universities, and organizations that provided content for this report.
      The 2024 report can be found online at https://www.nasa.gov/smallsat-institute/sst-soa. The report is also available in PDF format as a single document containing all report content as well as individual chapters available on their respective chapter webpages. This 2024 edition reflects updates in several chapters to include: the Formation Flying and Rendezvous and Proximity Operations section within the “Guidance, Navigation, and Control” chapter; the Additive Manufacturing section within the “Structures, Materials, and Mechanisms” chapter; the Free Space Optical Communications section within the “Communications” chapter; and the Hosted Orbital Services section within the “Complete Spacecraft Platforms” chapter.
      As in previous editions, the report contains a general overview of current state-of-the-art SmallSat technologies and their development status as discussed in open literature. The report is not intended to be an exhaustive representation of all technologies currently available to the small spacecraft community, nor does the inclusion of technologies in the report serve as an endorsement by NASA. Sources of publicly available date commonly used as sources in the development of the report include manufacturer datasheets, press releases, conference papers, journal papers, public filings with government agencies, and news articles. Readers are highly encouraged to reach out to companies for further information regarding the performance and maturity of described technologies of interest. During the report’s development, companies were encouraged to release test information and flight data when possible so it may be appropriately captured. It should be noted that technology maturity designations may vary with change to payload, mission requirements, reliability considerations, and the associated test/flight environment in which performance was demonstrated.
      Suggestions or corrections to the 2024 report toward a subsequent edition, should be submitted to the NASA Small Spacecraft Systems Virtual Institute Agency-SmallSat-Institute@mail.nasa.gov for consideration prior to the publication of the future edition. When submitting suggestions or corrections, please cite appropriate publicly accessible references. Private correspondence is not considered an adequate reference. Efforts are underway for the 2025 report and organizations are invited to submit technologies for consideration for inclusion by August 1, 2025.
      NASA’s Small Spacecraft Technology program within the Space Technology Mission Directorate funds the Small Spacecraft Systems Virtual Institute. 
      View the full article
    • By NASA
      “People are excited and happy about working at Goddard,” said optics engineer Margaret Dominguez. “Most people are willing to put in the extra effort if needed. It makes work stimulating and exciting. Management really cares and the employees feel that too.”Credits: Courtesy of Margaret Dominguez Name: Margaret Dominguez
      Formal Job Classification: Optical engineer
      Organization: Code 551, Optics Branch, Instrument Systems and Technology Division, Engineering Directorate
      What do you do and what is most interesting about your role here at Goddard? How do you help support Goddard’s mission?
      I build space telescopes. I am currently working on building one of the components for the Wide Field Instrument for the Roman Space Telescope. The component is called “Grism.” A grism is a combination of a grating and a prism.
      What is unique about your childhood?
      I went to high school in Tecamachalco in Puebla, Mexico, which is inland and south of Mexico City. My father raised pigs, chickens, rabbits, and cows. I am the oldest of four girls and two still live on the farm.
      Why did you become a physicist?
      I was always curious and had a lot of questions and thought that physics helped me answer some of these questions. I was good at math and loved it. When I told my dad I wanted to study physics, he said that I would be able to answer any question in the universe. He thought it was very cool.
      What is your educational background? How an internship help you come to Goddard?
      I went to the Universidad de las Americas Puebla college in Puebla and got an undergraduate degree in physics. I was very active in extracurricular activities and helped organize a physics conference. We invited Dr. Johnathan Gardner, a Goddard astronomer, who came to speak at the conference. Afterwards I spoke with him and he asked me if I was interested in doing an internship at NASA. I said I had not considered it and would be interested in applying. I applied that same spring of 2008 and got a summer internship in the Optics Branch, where I am still working today.
      My branch head at Goddard was a University of Arizona alumnus. He suggested that I apply to the University of Arizona for their excellent optics program. I did, and the university gave me a full fellowship for a master’s and a Ph.D. in optical sciences.
      In 2014, I began working full time at Goddard while completing my Ph.D. I graduated in May 2019.
      What makes Goddard special?
      Goddard has a university campus feel. It’s a place where you can work and also just hang out and socialize. Goddard has many clubs, a gym, cafeterias, and a health clinic.
      People are really nice here. They are often excited and happy about working at Goddard. Most people are willing to put in the extra effort if needed. It makes work stimulating and exciting. Management really cares and the employees feel that too.
      What are some of the major projects you have worked on?
      Early on, I did a little bit of work on Hubble and later on, NASA’s James Webb Space Telescope. Since 2014, I have exclusively been working on Roman. We are building the grism, a slitless spectrograph, which will measure galaxy redshifts to study dark energy.
      Presently we are building different grism prototypes. We work with outside vendors to build these prototypes. When we make a prototype, we test it for months. After, we use the results to build an improved prototype. We just finished making the third prototype. We are going to build a flight instrument of which the grism is a component.
      What is it like to work in the clean room?
      It’s exciting – it likely means I am working on flight hardware. However, because clean rooms must be kept at about 68 degrees Fahrenheit, it can feel chilly in there!
      Who are your mentors? What are the most important lessons they have taught you?
      Ray Ohl, the head of the Optics Branch, is a mentor to me. He is always encouraging me to get outside my comfort zone. He presents other opportunities to me so that I can grow and listens to my feedback.
      Cathy Marx, one of the Roman optical leads, is also a mentor to me. She created a support network for me and is a sounding board for troubleshooting any kind of work-related issues.
      What is your role a member of the Hispanic Advisory Committee (HACE)?
      I joined HACE in 2010 while I was an intern. It’s a great opportunity to network with other Hispanics and gives us a platform to celebrate specific events like Hispanic Heritage Month. I really enjoy participating in HACE’s events.
      What outreach do you do? Why is doing outreach so important to you?
      I do educational outreach to teach people about optics. I mainly collaborate with elementary and middle schools.
      I think we need more future engineers and scientists. I want to help recruit them. I specifically focus on recruiting minorities and Hispanics. I can make a special connection with women and Hispanics.
      Who is your science hero?
      It would probably be Marie Curie. She’s the first woman to win a Nobel Prize, and she is the only woman to win two Nobel Prizes and she had to overcome a lot of challenges to achieve that.
      What is your “six-word memoir”? A six-word memoir describes something in just six words.
      Disciplined. Organized. Diligent. Passionate. Curious. Family-oriented.
      Is there something surprising about your hobbies outside of work that people do not generally know?
      I am a certified Jazzercise instructor – I normally teach two to three times a week. I can even teach virtually if need be. It is an hour-long exercise class combining strength training and cardio through choreographed dancing. We also use weights and mats.  
      I also enjoy going for walks with my husband, James Corsetti, who is also an engineer in the Optics Branch.
      By Elizabeth M. Jarrell
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      Conversations With Goddard is a collection of Q&A profiles highlighting the breadth and depth of NASA’s Goddard Space Flight Center’s talented and diverse workforce. The Conversations have been published twice a month on average since May 2011. Read past editions on Goddard’s “Our People” webpage.
      View the full article
    • By NASA
      5 min read
      NASA CubeSat Finds New Radiation Belts After May 2024 Solar Storm
      Key Points
      The May 2024 solar storm created two new temporary belts of high-energy particles surrounding Earth. Such belts have been seen before, but the new ones were particularly long lasting, especially the new proton belt.  The findings are particularly important for spacecraft launching into geostationary orbits, which can be damaged as they traverse the dangerous belts. The largest solar storm in two decades hit Earth in May 2024. For several days, wave after wave of high-energy charged particles from the Sun rocked the planet. Brilliant auroras engulfed the skies, and some GPS communications were temporarily disrupted.
      With the help of a serendipitously resurrected small NASA satellite, scientists have discovered that this storm also created two new temporary belts of energetic particles encircling Earth. The findings are important to understanding how future solar storms could impact our technology. 
      The new belts formed between two others that permanently surround Earth called the Van Allen Belts. Shaped like concentric rings high above Earth’s equator, these permanent belts are composed of a mix of high-energy electrons and protons that are trapped in place by Earth’s magnetic field. The energetic particles in these belts can damage spacecraft and imperil astronauts who pass through them, so understanding their dynamics is key to safe spaceflight. 
      The May 2024 solar storm created two extra radiation belts, sandwiched between the two permanent Van Allen Belts. One of the new belts, shown in purple, included a population of protons, giving it a unique composition that hadn’t been seen before. NASA/Goddard Space Flight Center/Kristen Perrin The discovery of the new belts, made possible by NASA’s Colorado Inner Radiation Belt Experiment (CIRBE) satellite and published Feb. 6, 2025, in the Journal of Geophysical Research: Space Physics, is particularly important for protecting spacecraft launching into geostationary orbits, since they travel through the Van Allen Belts several times before reaching their final orbit.
      New Belts Amaze Scientists
      Temporary belts have been detected in the aftermath of large solar storms before. But while previous belts have been composed mostly of electrons, the innermost of the two new belts also included energetic protons. This unique composition is likely due to the strength and composition of the solar storm.
      “When we compared the data from before and after the storm, I said, ‘Wow, this is something really new,’” said the paper’s lead author Xinlin Li, a professor at the Laboratory for Atmospheric and Space Physics (LASP) and Department of Aerospace Engineering Sciences at the University of Colorado Boulder. “This is really stunning.”
      The new belts also seem to have lasted much longer than previous belts. Whereas previous temporary belts lasted around four weeks, the new belt composed primary of electrons lasted more than three months. The other belt, that also includes protons, has lasted much longer than the electron belt because it is in a more stable region and is less prone to the physical processes that can knock the particles out of orbit. It is likely still there today.
      “These are really high-energy electrons and protons that have found their way into Earth’s inner magnetic environment,” said David Sibeck, former mission scientist for NASA’s Van Allen Probes and research scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who was not involved with the new study. “Some might stay in this place for a very long time.”
      How long such belts stick around depends on passing solar storms. Large storms can provide the energy to knock particles in these belts out of their orbits and send them spiraling off into space or down to Earth. One such storm at the end of June significantly decreased the size of the new electron belt and another in August nearly erased the remainder of that electron belt, though a small population of high-energy electrons endured.
      CubeSat Fortuitously Comes Back to Life to Make the Discovery
      The new discovery was made by NASA’s CIRBE satellite, a CubeSat about the size of a shoebox that circled the planet’s magnetic poles in a low Earth orbit from April 2023 to October 2024. CIRBE housed an instrument called the Relativistic Electron Proton Telescope integrated little experiment-2 (REPTile-2) — a miniaturized and upgraded version of an instrument that flew aboard NASA’s Van Allen Probes, which made the first discovery of a temporary electron belt in 2013.
      The CIRBE CubeSat in the laboratory before launch. CIRBE was designed and built by LASP at the University of Colorado Boulder. Xinlin Li/LASP/CU Boulder After a year in space, the CubeSat experienced an anomaly and unexpectedly went quiet on April 15, 2024. The scientists were disappointed to miss the solar storm in May but were able to rely on other spacecraft to provide some preliminary data on the electron belt. Luckily, on June 15, the spacecraft sprang back to life and resumed taking measurements. The data provided high-resolution information that couldn’t be gleaned by any other instrument and allowed the scientists to understand the magnitude of the new belts.
      “Once we resumed measurements, we were able to see the new electron belt, which wasn’t visible in the data from other spacecraft,” Li said.
      Having the CubeSat in orbit to measure the effect of the solar storm has been bittersweet, Li said. While it provided the opportunity to measure the effects of such a large event, the storm also increased atmospheric drag on the CubeSat, which caused its orbit to decrease prematurely. As a result, the CubeSat deorbited in October 2024. However, the spacecraft’s data makes it all worth it.
      “We are very proud that our very small CubeSat made such a discovery,” Li said.
      CIRBE was designed and built by LASP at the University of Colorado Boulder and was launched through NASA’s CubeSat Launch Initiative (CSLI). The mission is sponsored by NASA’s Heliophysics Flight Opportunities for Research & Technology (H-FORT) program.
      By Mara Johnson-Groh
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      Share








      Details
      Last Updated Feb 06, 2025 Related Terms
      Heliophysics CubeSats Goddard Space Flight Center Heliophysics Division Ionosphere Space Weather The Sun Van Allen Probes Explore More
      5 min read Straight Shot: Hubble Investigates Galaxy with Nine Rings


      Article


      2 days ago
      2 min read Hubble Spots a Supernova


      Article


      6 days ago
      2 min read Hubble Studies the Tarantula Nebula’s Outskirts


      Article


      2 weeks ago
      Keep Exploring Discover More Topics From NASA
      Missions



      Humans in Space



      Climate Change



      Solar System


      View the full article
    • By European Space Agency
      Space is not the safest place to be. During spaceflight, both devices and humans risk exposure to high levels of radiation. Without sufficient protection, instruments would malfunction, and astronauts might face serious health risks. A team of researchers from Ghent University in Belgium are testing the potential of 3D-printed hydrogels – materials that can soak up large amounts of water – to serve as highly-effective radiation shields.
      View the full article
    • By NASA
      NASA’s Ames Research Center in Silicon Valley invites media to learn more about Distributed Spacecraft Autonomy (DSA), a technology that allows individual spacecraft to make independent decisions while collaborating with each other to achieve common goals – without human input. The DSA team achieved multiple firsts during tests of such swarm technology as part of the agency’s project. 
      DSA develops software tools critical for future autonomous, distributed, and intelligent spacecraft that will need to interact with each other to achieve complex mission objectives. Testing onboard the agency’s Starling mission resulted in accomplishments including the first fully distributed autonomous operation of multiple spacecraft, the first use of space-to-space communications to autonomously share status information between multiple spacecraft, and more. 
      DSA’s accomplishments mark a significant milestone in advancing autonomous systems that will make new types of science and exploration possible. 
      Caleb Adams, DSA project manager, is available for interview on Wednesday, Feb. 5 and Thursday, Feb. 6. To request an interview, media can contact the Ames Office of Communications by email at arc-dl-newsroom@nasa.gov or by phone at 650-604-4789.  
      Learn more about NASA Ames’ world-class research and development in aeronautics, science, and exploration technology at: 
      https://www.nasa.gov/ames
      -end- 
      Tiffany Blake
      Ames Research Center, Silicon Valley 
      650-604-4789 
      tiffany.n.blake@nasa.gov  

      To receive local NASA Ames news, email local-reporters-request@lists.arc.nasa.gov with “subscribe” in the subject line. To unsubscribe, email the same address with “unsubscribe” in the subject line.  

      View the full article
  • Check out these Videos

×
×
  • Create New...