25 Min Read The Marshall Star for May 29, 2024 
More to Marshall: Center Leadership Provides Updates During Spring All-Hands Meeting By Wayne Smith
NASA’s Marshall Space Flight Center will celebrate its 65th birthday next summer, and while there are plans to honor the center’s rich history, there is also More to Marshall ahead.
Team members at NASA’s Marshall Space Flight Center listen to Center Director Joseph Pelfrey, background center, share updates on culture and strategy during the spring all-hands meeting May 20 in Activities Building 4316. NASA/Danielle Burleson That was part of the message Center Director Joseph Pelfrey delivered during the spring all-hands meeting May 20 in Activities Building 4316. He highlighted Marshall’s transformative shift to more strategic partnerships across NASA and with industry, with the center continuing to serve as a technical solutions provider.
“More to Marshall is a systematic approach that will reinforce our center’s strategy and our role in space exploration,” Pelfrey said. “We align this vision with the core values of our Marshall fabric. We are not replacing our roots; we are fostering them to grow stronger and reach farther.”
Pelfrey also discussed the center’s evolving culture, highlighting April outreach activities, including the Total Solar Eclipse event in Russellville, Arkansas, First Robotics, Student Launch, and the Human Exploration Rover Challenge.
Marshall Deputy Director Rae Ann Meyer, second from right, responds to an audience question during a question-and-answer panel the May 20 all-hands meeting. At left, Lance D. Davis, Marshall’s public affairs and news chief, moderates the panel, while Pelfrey, center left, and Larry Leopard, Marshall’s associate director, technical, far right, listen in.NASA/Danielle Burleson “These events emulate the Marshall culture,” Pelfrey said. “I am proud of the impact you have on the community, the Artemis Generation, and across the globe.”
New Deputy Director Rae Ann Meyer followed Pelfrey’s opening remarks, focusing on the center’s newest culture initiatives. Meyer also invited Trace Turner, management assistant in the Office of the Director, to highlight the efforts of three Center Action Teams leading the charge on Marshall’s culture initiatives. Team leaders Rocio Garcia, Benjamin Ferrell, and Mason Quick each shared more about their respective team’s projects, including the development of a user-friendly app that will share information on Marshall, NASA’s Michoud Assembly Facility, Redstone Arsenal, and the community.
Larry Leopard, Marshall’s associate director, technical, provided an update on the center’s efforts to address knowledge management concerns, starting with events like Meals with Mentors, Center Strategy Brown Bags and Tech Talk presentations, and after-action reviews.
Center Action Team leader Rocio Garcia shares plans to develop a user-friendly app for Marshall team members and the public, which will serve as a one-stop shop for information on Marshall, NASA’s Michoud Assembly Facility, Redstone Arsenal, and the community.NASA/Danielle Burleson Finally, before Marshall leadership participated in a question-and-answer panel, Pelfrey shared updates on center strategy, infrastructure, NASA’s budget, and NASA 2040.
“We will build on the success of our center strategy,” Pelfrey said. “We will continue to implement and mature our pursuits culture, always seeking challenging and exciting opportunities, using our skills, expertise, capabilities, and infrastructure while continuing to build partnerships with industry and academia. Marshall has a tremendous role in returning humans to the Moon, reaching Mars, and exploring the cosmos.”
Team members can watch a recording of the all-hands meeting on Inside Marshall.
Smith, a Media Fusion employee and the Marshall Star editor, supports the Marshall Office of Communications.
Les Johnson Named Center Chief Technologist at Marshall Les Johnson has been named center chief technologist at NASA’s Marshall Space Flight Center, effective June 2.
Johnson will provide expert advice on technology initiatives to center leadership and to Marshall team members. He will lead the Marshall team on matters involving center-wide technology development. Johnson also will represent Marshall on NASA’s Center Technology Council and serves as the center’s focal point for Center Innovation Fund activities.
Les Johnson has been named center chief technologist at NASA’s Marshall Space Flight Center.NASA He has been a principal technologist for several of NASA’s advanced in-propulsion and power technology developments during his 33-year career at Marshall. Johnson served as the principal investigator of the Propulsive Small Expendable Deployer System (ProSEDS) tether propulsion project and Near-Earth Asteroid Scout solar sail mission. He was a co-investigator (Co-I) of the JAXA T-Rex tether propulsion demonstration, the European Union’s InflateSail, and NASA’s Lightweight Integrated Solar Array and anTenna (LISA-T) missions, as well as a Co-I on multiple NASA Innovative Advanced Concepts (NIAC) studies.
Johnson began his NASA career in 1990 working in the Program Development Directorate formulating new space science mission concepts. Shortly thereafter, he became the manager for NASA’s Interstellar Propulsion Technology Project that transitioned into the In-Space Propulsion Technology Program, which he managed on behalf of the Office of Space Science. He then served as the formulation manager for the Nuclear Systems Initiative, which became Project JIMO. Johnson served as deputy manager and technical assistant for the Advanced Concepts Office, before being selected to lead the development of the Solar Cruiser solar sail propulsion system in the Science and Technology Office.
Prior to NASA, he worked three years for General Research Corp. on directed energy systems in support of the Strategic Defense Initiative.
Johnson holds three patents. His awards include NASA’s Exceptional Technology Achievement Medal, NASA’s Exceptional Achievement Medal (twice), Marshall’s Technology Transfer and Innovation Awards, and he has been a Rotary Stellar Award finalist two times. As an outside activity, he is also an award-winning author.
A native of Ashland, Kentucky, Johnson earned his bachelor’s degree from Transylvania University and his master’s degree from Vanderbilt University.
Take 5 with Jose Matienzo By Wayne Smith
Growing up in the small village of Luquillo, Puerto Rico, Jose Matienzo would fly paper airplanes and launch model rockets from atop the building he lived in with his family.
“I knew then that I wanted to be some sort of engineer, I just didn’t know what it was called,” Matienzo said. “I never imagined that I actually would work for NASA, but I thought I could design cars or planes. I liked drawing them.”
Jose Matienzo began his NASA career in 1983 at the agency’s Marshall Space Flight Center.Photo courtesy of Jose Matienzo Flash forward more than five decades later. Matienzo is in his 42nd year working with NASA and the agency’s Marshall Space Flight Center as he nears retirement in December. Center team members will remember him as manager of the Marshall Exchange for the past 12 years, enjoying his witty daily email from the Exchange.
“Literally every day was fun trying to make life better for our team members,” Matienzo said of his team with the Exchange. “That includes bringing the food truck court, being able to have employee clothing of all styles and types, creating new clubs, and expanding facilities.”
He is currently assigned to a position with NASA’s Source Evaluation Board.
As he approaches retirement, Matienzo still finds it difficult to fathom his many milestones working with NASA and Marshall, where he began his career in 1983 as a co-op student in the structural dynamics division and worked on the Space Shuttle Program for 12 years. Matienzo followed that with a year at NASA Headquarters before returning to Marshall as lead engineer on several projects related to the International Space Station, such as the space station element transportation system.
His other assignments have included managing the NASA office at the Naval Research Center; the Marshall lead for supporting the Launch Services Program, including the office at the United Launch Alliance rocket plant in Decatur; technical assistant for former Marshall Director Robert Lightfoot; and more.
“There have been so many memories over the years,” Matienzo said. “Six months after becoming a full-time employee, the Challenger accident happened. At the time I had no idea what the possible impact of that accident would be. We all had a little part on returning to flight, so watching the first launch afterwards was a fantastic moment.
“We delivered space station hardware in partnership with the Italians and the European Space Agency, helped train the astronauts who performed the Hubble Telescope repair, and most recently, we made improvements to the Exchange services to make life at work better for our employees.”
Question: What excites you most about the future of human space exploration, or your NASA work, and your team’s role it?
Matienzo: I’ve been here for a long time and our future missions and goals have changed over the years. But no matter what, there’s always been excitement about meeting the agency’s goals and Marshall’s role in providing space transportation, lunar landers, and even Mars sample return vehicles. That and all of the support and testing work that comes with it is fun!
Question: Who or what drives/motivates you?
Matienzo: I’ve been lucky that my job assignments have always been fun and self-motivating, but certainly dealing and coordinating with colleagues in accomplishing a mutual goal, test, or assignment is very rewarding.
Question: What advice do you have for employees early in their NASA career or those in new leadership roles?
Matienzo: Network! As you get to know others and learn what they do, you will find out how everything comes together at NASA and where other opportunities may be out there for you. For our leaders: keep encouraging, mentoring, and creating opportunities for the employees to experience, learn, and grow.
Question: What do you enjoy doing with your time while away from work?
Matienzo: My kids are older now so keeping in touch is fun. But I do have grandkids to play with. Otherwise, I play congas with my bandmates, love to do social dancing, play lots of pickleball, and enjoy mountain and road bike riding.
Question: What plans do you have for retirement?
Matienzo: I want to move closer to the beach. I love Huntsville, so I want to keep a presence here. I also plan to bike all over the USA!
Smith, a Media Fusion employee and the Marshall Star editor, supports the Marshall Office of Communications.
Marshall Team Supports Safe Travels for Space Station Science By Jessica Barnett
During the International Space Station’s more than 25 years of operation, there have been more than 3,000 experiments conducted aboard the microgravity laboratory, and making sure scientific samples are kept safe through launch, spaceflight, experimentation, and the return trip to Earth takes a great deal of planning, testing, and preparation across NASA.
In February, team members at NASA’s Marshall Space Flight Center handled the de-integration of zinc selenide-based crystals grown on the space station as part of an experiment to study how a lack of gravity might affect the crystals’ growth and structure. The experiment was conducted using six sample cartridge assemblies heated up to 1,200 degrees Celsius (2,192 degrees Fahrenheit) inside the Materials Science Laboratory of the Materials Science Research Rack on the space station.
NASA Marshall Space Flight Center’s payload technician Chris Honea, left, and quality assurance specialist Keith Brandon, right, on Feb. 29 carefully inspect the temperature sensors that help gather data and monitor progress during a crystals experiment. The zinc selenide-based crystals were grown on the International Space Station as part of an experiment to see how gravity affects their structure or growth, then de-integrated and inspected in Marshall’s Space Systems Integration & Test Facility.NASA John Luke Bili, lead systems test engineer for the sample cartridge assemblies within Marshall’s Instrument Development, Integration, and Test Branch, begins the process by working with engineers, scientists, project personnel, and the experiment’s principal investigator to create an ampoule, or sealed glass vial, to use as a sample container.
“We’ll take the ampoule and do some ground testing, like a normal flight integration,” Bili said. “We’ll assemble it with the hardware we have, then we are responsible for completing different mitigation efforts to prepare for sealing the ampoule up and processing it at the required high temperatures.”
The team exposes the test article to extreme heat and pressure using a duplicate of the furnace on the space station, allowing them to also test the experiment’s software.
The zinc selenide-based crystal experiment required six sample cartridge assemblies. After a month of preparation from Marshall’s team, the assemblies traveled to NASA’s Johnson Space Center for a final round of packing before arriving at the agency’s Kennedy Space Center for launch.
The assemblies launched on NASA’s SpaceX 24th commercial resupply services mission in December 2021 and NASA’s Northrop Grumman 19th commercial resupply services mission in August 2023. Each sample took about a week to process through the space station’s lab furnace. The samples were then brought back to Earth, with three of the six arriving at Marshall on Feb. 9.
An ampoule containing zinc selenide-based crystals rests on a table in Marshall Space Flight Center’s Space Systems Integration & Test Facility. The ampoule was part of the sixth sample cartridge assembly retrieved from the International Space Station as part of an experiment to see how gravity affects the crystals’ structure or growth.NASA While unpacking the crystal samples, team members took photos and notes of the tubes throughout the de-integration process in Marshall’s Space Systems Integration & Test Facility. The team includes technicians with 20 to 30 years of experience, ensuring samples safely travel to and from the station and helping expand access for researchers to explore microgravity, space exposure, and future missions in low Earth orbit.
“It’s really nice having that kind of experience when we’re working on the hardware that’s going in space,” he said. “We’ve got a lot of people that are very skilled machinists that are able to help us in a moment’s notice, we have people with a really good understanding of technical tolerances and stuff like that, and we have people with a lot of varying experience doing flight hardware integration and tests.”
For more than two decades, humans have lived and worked continuously aboard the International Space Station, advancing scientific knowledge and making research breakthroughs that are not possible on Earth. The station is a critical testbed for NASA to understand and overcome the challenges of long-duration spaceflight and to expand commercial opportunities in low Earth orbit.
Learn more about the space station.
Barnett, a Media Fusion employee, supports the Marshall Office of Communications.
Spotted: ‘Death Star’ Black Holes in Action A team of astronomers have studied 16 supermassive black holes that are firing powerful beams into space, to track where these beams, or jets, are pointing now and where they were aimed in the past, as reported in a press release. Using NASA’s Chandra X-ray Observatory and the U.S. National Science Foundation (NSF) National Radio Astronomical Observatory’s (NRAO) Very Large Baseline Array (VLBA), they found that some of the beams have changed directions by large amounts.
These two Chandra images show hot gas in the middle of the galaxy cluster Abell 478, left, and the galaxy group NGC 5044, right.X-ray: NASA/CXC/Univ. of Bologna/F. Ubertosi; Insets Radio: NSF/NRAO/VLBA; Wide field Image: Optical/IR: Univ. of Hawaii/Pan-STARRS; Image Processing: NASA/CXC/SAO/N. Wolk These two Chandra images show hot gas in the middle of the galaxy cluster Abell 478 (left) and the galaxy group NGC 5044 (right). The center of each image contains one of the sixteen black holes firing beams outwards. Each black hole is in the center of a galaxy embedded in the hot gas.
In the images below, labels and the radio images appear. Ellipses show a pair of cavities in the hot gas for Abell 478, left, and ellipses show two pairs of cavities for NGC 5044, right. These cavities were carved out by the beams millions of years ago, giving the directions of the beams in the past. An X shows the location of each supermassive black hole.
The VLBA images are shown as insets, which reveal where the beams are currently pointing, as seen from Earth. The radio images are both much smaller than the X-ray images. For Abell 478 the radio image is about 3% of the width of the Chandra image and for NGC 5044 the radio image is about 4% of the Chandra image’s width.
A labeled version of the image.X-ray: NASA/CXC/Univ. of Bologna/F. Ubertosi; Insets Radio: NSF/NRAO/VLBA; Wide field Image: Optical/IR: Univ. of Hawaii/Pan-STARRS; Image Processing: NASA/CXC/SAO/N. Wolk A comparison between the Chandra and VLBA images shows that the beams for Abell 478 changed direction by about 35 degrees and the beams for NGC 5044 changed direction by about 70 degrees.
Across the entire sample the researchers found that about a third of the 16 galaxies have beams that are pointing in completely different directions than they were before. Some have changed directions by nearly 90 degrees in some cases, and over timescales between one million years and a few tens of millions of years. Given that the black holes are of the order of 10 billion years old, this represents a relatively rapid change for these galaxies.
Black holes generate beams when material falls onto them via a spinning disk of matter and some of it then gets redirected outward. The direction of the beams from each of these giant black holes, which are likely spinning, is thought to align with the rotation axis of the black hole, meaning that the beams point along a line connecting the poles.
These beams are thought to be perpendicular to the disk. If material falls towards the black holes at a different angle that is not parallel to the disk, it could affect the direction of the black hole’s rotation axes, changing the direction of the beams.
![Wide Field Views of Abell 478 [Left] and NGC 5044 [Right].](https://www.nasa.gov/wp-content/uploads/2024/05/deathstars-x-ray-optical-wide.jpg?w=2048)
Wide field views of Abell 478, left, and NGC 5044, right.X-ray: NASA/CXC/Univ. of Bologna/F. Ubertosi et al.; Optical/IR: Univ. of Hawaii/Pan-STARRS; IR: NASA/ESA/JPL/CalTech/Herschel Space Telescope Scientists think that beams from black holes and the cavities they carve out play an important role in how many stars form in their galaxies. The beams pump energy into the hot gas in and around the galaxy, preventing it from cooling down enough to form huge numbers of new stars. If the beams change directions by large amounts, they can tamp down star formation across much larger areas of the galaxy.
The paper describing these results was published in the January 20th, 2024 issue of The Astrophysical Journal, and is available here. The authors are Francesco Ubertosi (University of Bologna in Italy), Gerritt Schellenberger (Center for Astrophysics | Harvard & Smithsonian), Ewan O’Sullivan (CfA), Jan Vrtilek (CfA), Simona Giacintucci (Naval Research Laboratory), Laurence David (CfA), William Forman (CfA), Myriam Gitti (University of Bologna), Tiziana Venturi (National Institute of Astrophysics—Institute of Radio Astronomy in Italy), Christine Jones (CfA), and Fabrizio Brighenti (University of Bologna).
NASA’s Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science from Cambridge Massachusetts and flight operations from Burlington, Massachusetts.
Read more from NASA’s Chandra X-ray Observatory.
NASA, IBM Research to Release New AI Model for Weather, Climate By Jessica Barnett
Working together, NASA and IBM Research have developed a new artificial intelligence model to support a variety of weather and climate applications. The new model – known as the Prithvi-weather-climate foundational model – uses artificial intelligence (AI) in ways that could vastly improve the resolution we’ll be able to get, opening the door to better regional and local weather and climate models.
Foundational models are large-scale, base models which are trained on large, unlabeled datasets and can be fine-tuned for a variety of applications. The Prithvi-weather-climate model is trained on a broad set of data – in this case NASA data from NASA’s Modern-Era Retrospective analysis for Research and Applications (MERRA-2)– and then makes use of AI learning abilities to apply patterns gleaned from the initial data across a broad range of additional scenarios.
With the Prithvi-weather-climate foundational model, researchers will be able to support many climate applications that can be used throughout the science community. These applications include detecting and improving models for severe weather patterns or natural disasters such as hurricanes. NASA’s Terra satellite acquired this image of Idalia in August 2023. NASA Earth Observatory “Advancing NASA’s Earth science for the benefit of humanity means delivering actionable science in ways that are useful to people, organizations, and communities. The rapid changes we’re witnessing on our home planet demand this strategy to meet the urgency of the moment,” said Karen St. Germain, director of the Earth Science Division of NASA’s Science Mission Directorate. “The NASA foundation model will help us produce a tool that people can use: weather, seasonal and climate projections to help inform decisions on how to prepare, respond and mitigate.”
With the Prithvi-weather-climate model, researchers will be able to support many different climate applications that can be used throughout the science community. These applications include detecting and predicting severe weather patterns or natural disasters, creating targeted forecasts based on localized observations, improving spatial resolution on global climate simulations down to regional levels, and improving the representation of how physical processes are included in weather and climate models.
“These transformative AI models are reshaping data accessibility by significantly lowering the barrier of entry to using NASA’s scientific data,” said Kevin Murphy, NASA’s chief science data officer, Science Mission Directorate at NASA Headquarters. “Our open approach to sharing these models invites the global community to explore and harness the capabilities we’ve cultivated, ensuring that NASA’s investment enriches and benefits all.”
Prithvi-weather-climate was developed through an open collaboration with IBM Research, Oak Ridge National Laboratory, and NASA, including the agency’s Interagency Implementation and Advanced Concepts Team (IMPACT) at NASA’s Marshall Space Flight Center.
Prithvi-weather-climate can capture the complex dynamics of atmospheric physics even when there is missing information thanks to the flexibility of the model’s architecture. This foundational model for weather and climate can scale to both global and regional areas without compromising resolution.
“This model is part of our overall strategy to develop a family of AI foundation models to support NASA’s science mission goals,” said Rahul Ramachandran, who leads IMPACT at Marshall. “These models will augment our capabilities to draw insights from our vast archives of Earth observations.”
Prithvi-weather-climate is part of a larger model family– the Prithvi family – which includes models trained on NASA’s Harmonized LandSat and Sentinel-2 data. The latest model serves as an open collaboration in line with NASA’s open science principles to make all data accessible and usable by communities everywhere. It will be released later this year on Hugging Face, a machine learning and data science platform that helps users build, deploy, and train machine learning models.
“The development of the NASA foundation model for weather and climate is an important step towards the democratization of NASA’s science and observation mission,” said Tsendgar Lee, program manager for NASA’s Research and Analysis Weather Focus Area, High-End Computing Program, and Data for Operation and Assessment. “We will continue developing new technology for climate scenario analysis and decision making.”
Along with IMPACT and IBM Research, development of Prithvi-weather-climate featured significant contributions from NASA’s Office of the Chief Science Data Officer, NASA’s Global Modeling and Assimilation Office at Goddard Space Flight Center, Oak Ridge National Laboratory, the University of Alabama in Huntsville, Colorado State University, and Stanford University.
Learn more about Earth data and previous Prithvi models.
Barnett, a Media Fusion employee, supports the Marshall Office of Communications.
Psyche Fires Up Its Sci-Fi-Worthy Thrusters NASA’s Psyche spacecraft passed its six-month checkup with a clean bill of health, and there’s no holding back now. Navigators are firing its futuristic-looking electric thrusters, which emit a blue glow, nearly nonstop as the orbiter zips farther into deep space.
The spacecraft launched from NASA’s Kennedy Space Center atop a SpaceX Falcon Heavy on Oct. 13, 2023. After leaving Earth’s atmosphere, Psyche made the most of its rocket boost and coasted beyond the orbit of Mars.
For the next year, the spacecraft will be in what mission planners call “full cruise” mode, when its electric thrusters take over and propel the orbiter toward the asteroid belt. The thrusters work by expelling charged atoms, or ions, of xenon, emitting a brilliant blue glow that trails behind the spacecraft.
This artist’s concept depicts NASA’s Psyche spacecraft headed to the metal-rich asteroid Psyche in the main asteroid belt between Mars and Jupiter. The spacecraft launched in October 2023 and will arrive at its destination in 2029.NASA/JPL-Caltech/ASU They are part of Psyche’s incredibly efficient solar electric propulsion system, which is powered by sunlight. The thrust created by the ionized xenon is gentle, but it does the job. Even in full cruise mode, the pressure exerted by the thrusters is about what you’d feel holding three quarters in your hand.
The orbiter is now more than 190 million miles away and moving at a clip of 23 miles per second, relative to Earth. That’s about 84,000 mph. Over time, with no atmospheric drag to slow it down, Psyche will accelerate to speeds of up to 124,000 mph.
The spacecraft will arrive at the metal-rich asteroid Psyche in 2029 and will make observations from orbit for about two years. The data it collects will help scientists better understand the formation of rocky planets with metallic cores, including Earth. Scientists have evidence that the asteroid, which is about 173 miles across at its widest point, may be the partial core of a planetesimal, the building block of an early planet.
The flight team used Psyche’s first 100 days in space to conduct a full checkout of all spacecraft systems. All of the engineering systems are working just as expected, and the three science instruments have been operating without a hitch. The magnetometer is working so well that it was able to detect an eruption of charged particles from the Sun, as did the gamma-ray and neutron spectrometer. And this past December, the twin cameras on the imaging instrument captured their first images.
This photo captures an operating electric thruster identical to those being used to propel NASA’s Psyche spacecraft. The blue glow comes from the charged atoms, or ions, of xenon.NASA/JPL-Caltech “Until this point, we have been powering on and checking out the various pieces of equipment needed to complete the mission, and we can report they are working beautifully,” said Henry Stone, Psyche project manager at NASA’s Jet Propulsion Laboratory, which manages the mission. “Now we are on our way and looking forward to an upcoming close flyby of Mars.”
That’s because the spacecraft’s trajectory will bring it back toward the Red Planet in the spring of 2026. The spacecraft will power down the thrusters as it coasts toward Mars, using the planet’s gravity to slingshot itself out. From there, the thrusters return to full cruise mode. Next stop: the asteroid Psyche.
In the meantime, the Deep Space Optical Communications technology demonstration aboard the spacecraft will keep on testing its mettle. The experiment already surpassed expectations when, in April, it transmitted test data from over 140 million miles away at a rate of 267 megabits per second to a downlink station on Earth – a bit rate comparable to broadband internet download speeds.
Arizona State University leads the Psyche mission. A division of Caltech in Pasadena, JPL is responsible for the mission’s overall management, system engineering, integration and test, and mission operations. Maxar Technologies in Palo Alto, California, provided the high-power solar electric propulsion spacecraft chassis.
JPL manages DSOC for the Technology Demonstration Missions program within NASA’s Space Technology Mission Directorate and the Space Communications and Navigation program within the Space Operations Mission Directorate.
Psyche is the 14th mission selected as part of NASA’s Discovery Program, which is managed by the agency’s Marshall Space Flight Center. NASA’s Launch Services Program, based at Kennedy, managed the launch service.
NASA’s OSIRIS-APEX Unscathed After Searing Pass of Sun Mission engineers were confident NASA’s OSIRIS-APEX (Origins, Spectral Interpretation, Resource Identification – Apophis Explorer) spacecraft could weather its closest ever pass of the Sun on Jan. 2. Their models had predicted that, despite traveling 25 million miles closer to the heat of the Sun than it was originally designed to, OSIRIS-APEX and its components would remain safe.
The mission team confirmed that the spacecraft indeed had come out of the experience unscathed after downloading stored telemetry data in mid-March. The team also tested OSIRIS-APEX’s instruments in early April, once the spacecraft was far enough from the Sun to return to normal operations. Between December 2023 and March, OSIRIS-APEX was inactive, with only limited telemetry data available to the team on Earth.
Both these images from a camera called StowCam aboard OSIRIS-APEX show the same view taken six months apart, before, left, and after, right, the Jan. 2, 2024, perihelion. Notably, there is no observable difference on spacecraft surfaces, a good indication that the higher temperatures faced during perihelion didn’t alter the spacecraft. Another insight gleaned from the identical view in the two images is that the camera’s performance was also not affected by perihelion. NASA/University of Arizona/Lockheed Martin The spacecraft’s clean bill of health was due to creative engineering. Engineers placed OSIRIS-APEX in a fixed orientation with respect to the Sun and repositioned one of its two solar arrays to shade the spacecraft’s most sensitive components during the pass.
The spacecraft is in an elliptical orbit around the Sun that brings it to a point closest to the Sun, called a perihelion, about every nine months. To get on a path that will allow it to meet up with its new target Apophis in 2029, the spacecraft’s trajectory includes several perihelions that are closer to the Sun than the spacecraft’s components were originally designed to withstand.
“It’s phenomenal how well our spacecraft configuration protected OSIRIS-APEX, so I’m really encouraged by this first close perihelion pass,” said Ron Mink, mission systems engineer for OSIRIS-APEX, based at NASA’s Goddard Space Flight Center.
Besides confirming that the January perihelion worked out according to predictions, engineers found surprises while testing spacecraft components. A couple of instruments came out better than expected after exposure to higher temperatures.
A camera that helped map asteroid Bennu and will do the same at Apophis, saw a 70% reduction in “hot pixels” since April 13, 2023, the last time it was tested. Hot pixels, which are common in well-used cameras in space, show up as white spots in images when detectors accumulate exposure to high-energy radiation, mostly from our Sun.
“We think the heat from the Sun reset the pixels through annealing,” said Amy Simon, OSIRIS-APEX project scientist, based at NASA Goddard. Annealing is a heat process that can restore function of instruments and is often done intentionally through built-in heaters on some spacecraft.
Another welcome surprise, said Simon, came from the spacecraft’s visible and near-infrared spectrometer. Before perihelion, the spectrometer, which mapped the surface composition of Bennu, and will do the same at Apophis, seemed to have a rock from Bennu stuck inside its calibration port. Scientist suspected that some sunlight was blocked from filtering through the instrument after the spacecraft, then called OSIRIS-REx, grabbed a sample from asteroid Bennu on Oct. 20, 2020. By picking up the sample and then firing its engines to back away from Bennu, the spacecraft stirred up dust and pebbles that clung to it.
“But, with enough spacecraft maneuvers and engine burns after sample collection,” Simon said, the rock in the calibration port appears to have been dislodged. Scientists will check the spectrometer again when OSIRIS-APEX swings by Earth on Sept. 25, 2025, for a gravitational boost.
OSIRIS-APEX is now operating normally as it continues its journey toward asteroid Apophis for a 2029 rendezvous. Its better-than-expected performance during the first close perihelion is welcome news. But engineers caution that it doesn’t mean it’s time to relax. OSIRIS-APEX needs to execute five more exceptionally close passes of the Sun – along with three Earth gravity assists – to get to its destination. It’s unclear how the cumulative effect of six perihelions at a closer distance than designed will impact the spacecraft and its components.
The second OSIRIS-APEX perihelion is scheduled for Sept. 1. The spacecraft will be 46.5 million miles away from the Sun, which is roughly half the distance between Earth and the Sun, and well inside the orbit of Venus.
OSIRIS-APEX (previously named OSIRIS-REx) is the third mission in NASA’s New Frontiers Program, managed by NASA’s Marshall Space Flight Center in for the agency’s Science Mission Directorate.