Topic: NASA's Lucy mission to the Trojan asteroids
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 01-04-2017 02:34 PM
NASA release
NASA Selects Lucy Mission to Explore the Early Solar System
NASA has selected a mission that has the potential to open a new window on one of the earliest eras in the history of our solar system — a time less than 10 million years after the birth of our sun. The mission, known as Lucy, was chosen from five finalists and will proceed to mission formulation, with the goal of launching in 2021.
"Lucy will visit a target-rich environment of Jupiter's mysterious Trojan asteroids," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate in Washington. "This is what Discovery Program missions are all about — boldly going to places we've never been to enable groundbreaking science."
Lucy, a robotic spacecraft, is scheduled to launch in October 2021. It's slated to arrive at its first destination, a main belt asteroid, in 2025. From 2027 to 2033, Lucy will explore six Jupiter Trojan asteroids. These asteroids are trapped by Jupiter's gravity in two swarms that share the planet's orbit, one leading and one trailing Jupiter in its 12-year circuit around the sun. The Trojans are thought to be relics of a much earlier era in the history of the solar system, and may have formed far beyond Jupiter's current orbit.
"This is a unique opportunity," said Harold F. Levison, principal investigator of the Lucy mission from the Southwest Research Institute in Boulder, Colorado. "Because the Trojans are remnants of the primordial material that formed the outer planets, they hold vital clues to deciphering the history of the solar system. Lucy, like the human fossil for which it is named, will revolutionize the understanding of our origins."
Lucy will build on the success of NASA's New Horizons mission to Pluto and the Kuiper Belt, using newer versions of the RALPH and LORRI science instruments that helped enable the mission's achievements. Several members of the Lucy mission team also are veterans of the New Horizons mission. Lucy also will build on the success of the OSIRIS-REx mission to asteroid Bennu, with the OTES instrument and several members of the OSIRIS-REx team.
"These are true missions of discovery that integrate into NASA's larger strategy of investigating how the solar system formed and evolved," said NASA's Planetary Science Director Jim Green. "We've explored terrestrial planets, gas giants, and a range of other bodies orbiting the sun. Lucy will observe primitive remnants from farther out in the solar system."
Discovery Program class missions like this are relatively low-cost, their development capped at about $450 million. They are managed for NASA's Planetary Science Division by the Planetary Missions Program Office at Marshall Space Flight Center in Huntsville, Alabama. The missions are designed and led by a principal investigator, who assembles a team of scientists and engineers, to address key science questions about the solar system.
The Discovery Program portfolio includes 12 prior selections such as the MESSENGER mission to study Mercury, the Dawn mission to explore asteroids Vesta and Ceres, and the InSight Mars lander, scheduled to launch in May 2018.
NASA's other missions to asteroids began with the NEAR orbiter of asteroid Eros, which arrived in 2000, and continues with Dawn, which orbited Vesta and now is in an extended mission phase at Ceres. The OSIRIS-REx mission, which launched on Sept. 8, 2016, is speeding toward a 2018 rendezvous with the asteroid Bennu, and will deliver a sample back to Earth in 2023. Each mission focuses on a different aspect of asteroid science to give scientists the broader picture of solar system formation and evolution.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 01-05-2017 11:26 AM
Lockheed Martin release
Lockheed Martin to Build NASA's Lucy Spacecraft, a Mission to Trojan Asteroids
NASA's Newest Discovery Mission to Study Asteroids Orbiting with Jupiter
Lockheed Martin has been selected to design, build and operate the spacecraft for NASA's Lucy mission. One of NASA's two new Discovery Program missions, Lucy will perform the first reconnaissance of the Jupiter Trojan asteroids orbiting the sun in tandem with the gas giant. The Lucy spacecraft will launch in 2021 to study six of these exciting worlds.
The mission is led by Principal Investigator Dr. Harold Levison of the Southwest Research Institute in Boulder, Colorado. NASA's Goddard Space Flight Center in Greenbelt, Maryland will manage the mission. The program has a development cost cap of about $450 million.
"This is a thrilling mission as the Jupiter Trojan asteroids have never been studied up close," said Guy Beutelschies, director of Interplanetary Systems at Lockheed Martin Space Systems. "The design of the spacecraft draws from the flight-proven OSIRIS-REx spacecraft currently on its way to a near-Earth asteroid. This heritage of spacecraft and mission operations brings known performance, reliability and cost to the mission."
Lucy will study the geology, surface composition and bulk physical properties of these bodies at close range. It's slated to arrive at its first destination, a main belt asteroid, in 2025. From 2027 to 2033, Lucy will explore six Jupiter Trojan asteroids. These asteroids are trapped by Jupiter's gravity in two swarms that share the planet's orbit, one leading and one trailing Jupiter in its 12-year circuit around the sun. The Trojans are thought to be relics of a much earlier era in the history of the solar system, and may have formed far beyond Jupiter's current orbit.
"This is a unique opportunity," said Dr. Levison. "Because the Trojans are remnants of the primordial material that formed the outer planets, they hold vital clues to deciphering the history of the solar system. Lucy, like the human fossil for which it is named, will revolutionize the understanding of our origins."
Lucy is the seventh NASA Discovery Program mission in which Lockheed Martin has participated. Previously, the company developed the Lunar Prospector spacecraft; developed the aeroshell entry system for Mars Pathfinder; developed and operated the spacecraft for both Stardust missions; developed and operated the Genesis spacecraft; developed and operated the two GRAIL spacecraft; and developed and will operate the InSight Mars lander set to launch in May 2018.
NASA's Discovery program class missions are relatively low-cost, their development capped at a specific cost. They are managed for NASA's Planetary Science Division by the Planetary Missions Program Office at Marshall Space Flight Center in Huntsville, Alabama. The missions are designed and led by a principal investigator, who assembles a team of scientists and engineers, to address key science questions about the solar system.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 01-31-2019 09:29 PM
United Launch Alliance release
NASA Selects United Launch Alliance's Reliable Atlas V Rocket to Launch Lucy Mission to Jupiter's Trojan Asteroids
NASA's Launch Services Program announced today that it selected United Launch Alliance's (ULA's) proven Atlas V vehicle to launch the Lucy mission, which is the first mission to Jupiter's swarm of Trojan asteroids. This award resulted from a competitive Launch Service Task Order evaluation under the NASA Launch Services II contract.
"We could not be more pleased that NASA has selected ULA to launch this amazing planetary science mission," said Tory Bruno, ULA's president and chief executive officer. "This mission has a once-in-a-lifetime planetary launch window, and Atlas V's world-leading schedule certainty, coupled with our reliability and performance provided the optimal vehicle for this mission. Our Atlas V rocket has launched 79 times achieving 100 percent mission success, and we look forward to working again with our mission partners to explore our universe."
The Lucy mission is scheduled to launch in October 2021 from Space Launch Complex-41 at Cape Canaveral Air Force Station in Florida. This mission will launch aboard an Atlas V 401 configuration rocket.
Atlas V has a strong history in launching planetary missions for NASA including Mars Science Lab; New Horizons; OSIRIS-REx, the first U.S. mission to return asteroid samples to Earth; and the Solar Dynamics Observatory to study the sun.
Jupiter's swarms of Trojan asteroids may be remnants of the primordial material that formed the outer planets, and serve as time capsules from the birth of our solar system more than 4 billion years ago. Lucy will be the first space mission to study the Trojans. The mission takes its name from the fossilized human ancestor (named "Lucy" by her discoverers) whose skeleton provided unique insight into humanity's evolution. Lucy will complete a 12-year journey to seven different asteroids.
With more than a century of combined heritage, ULA is the world's most experienced and reliable launch service provider. ULA has successfully delivered 132 missions to orbit that provide Earth observation capabilities, enable global communications, unlock the mysteries of our solar system, and support life-saving technology.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 08-03-2020 10:45 AM
Southwest Research Institute (SwRI) release
SwRI-led Lucy mission one step closer to the Trojan asteroids
NASA's Lucy mission, led by Southwest Research Institute (SwRI), has achieved an important milestone by passing its System Integration Review and clearing the way for spacecraft assembly. This NASA Discovery Program class mission will be the first to explore Jupiter's Trojan asteroids, ancient small bodies that share an orbit with Jupiter and hold important insights to understanding the early solar system.
Above: This artist’s concept shows the Lucy spacecraft observing a Trojan asteroid. (NASA/Lockheed Martin)
The Lucy spacecraft, during its nominal 12-year mission, will fly by and collect data from seven of these primitive worlds, plus a main belt asteroid. Because the Trojan asteroids are remnants of the primordial material that formed the outer planets, they hold vital clues to deciphering the history of the solar system. Lucy, like the human fossil for which it is named, will revolutionize the understanding of our origins.
Over the last few months, the Lucy team has focused on building and testing all the components of the spacecraft, including the scientific instruments, electronics, communications and navigation systems while observing all appropriate pandemic protocols. At this review, the Lucy team demonstrated to an independent senior review board, including NASA and external experts, that the systems and subsystems are on schedule to proceed to assembly, testing and integration.
The virtual review was held the week of July 27, 2020, with all team members and panel experts participating from their homes.
"No one anticipated that we would be building a spacecraft under these circumstances," said Lucy Principal Investigator Dr. Hal Levison of SwRI. "But once again, I have been impressed by this team's creativity and resiliency to overcome any and all challenges placed before them."
Above: A Lucy team member installs the scan mirror on the L’Ralph Instrument at NASA’s Goddard Space Flight Center in preparation for integration into the spacecraft. (NASA)
Successful completion of this review means the project can proceed with assembling and testing the spacecraft in preparation for launch. This assembly phase will begin later this month at the Lockheed Martin Space Systems facilities in Littleton, Colorado. Due to interruptions caused by the pandemic, the team revised its schedule to allow components most impacted to be integrated into the spacecraft at later times. Through these efforts, the mission has been able to stay on track to launch as planned in October 2021.
"It has been hard not being able to get together as a team and not being able to travel to see the instruments being built and tested," says Deputy Principal Investigator Dr. Cathy Olkin, also of SwRI. "Still, the team really has surpassed themselves, keeping everyone safe while still carrying out the crucial operations needed to get the mission past this major milestone."
Over the next six months, Goddard Spaceflight Center, Johns Hopkins University Applied Physics Laboratory and Arizona State University will deliver a suite of complementary imaging and mapping instruments to Lockheed Martin to be integrated into the spacecraft. This payload will enable Lucy to investigate, map and analyze this enigmatic population of Trojan asteroids.
SwRI is the principal investigator institution and leads the mission. Goddard will provide overall project management, systems engineering, and safety and mission assurance.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 01-06-2021 10:58 AM
NASA release
NASA's First Mission to the Trojan Asteroids Integrates its Second Scientific Instrument
NASA's Lucy mission is one step closer to launch as L'TES, the Lucy Thermal Emission Spectrometer, has been successfully integrated on to the spacecraft.
Above: L'TES instrument in the cleanroom at Arizona State University. (NASA/ASU)
"Having two of the three instruments integrated onto the spacecraft is an exciting milestone," said Donya Douglas-Bradshaw, Lucy project manager from NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The L'TES team is to be commended for their true dedication and determination."
Lucy will be the first space mission to study the Trojan asteroids, leftover building blocks of the Solar System's outer planets orbiting the Sun at the distance of Jupiter. The mission takes its name from the fossilized human ancestor (called "Lucy" by her discoverers) whose skeleton provided unique insight into humanity's evolution. Likewise, the Lucy mission will revolutionize our knowledge of planetary origins and the birth of our solar system more than 4 billion years ago.
L'TES, developed by a team at Arizona State University (ASU), is effectively a remote thermometer. It will measure the far infrared energy emitted by the Trojan asteroids as the Lucy spacecraft flies by an unprecedented seven of these objects during this first ever mission to this population.
The instrument arrived at Lockheed Martin Space on December 13 and was successfully integrated on to the spacecraft on December 16. By measuring the Trojan asteroids' temperatures, L'TES will provide the team with important information on the material properties of the surfaces. As the spacecraft will not be able to touch down on the asteroids during these high speed encounters, this instrument will allow the team to infer whether the surface material is loose, like sand, or consolidated, like rocks. In addition, L'TES will collect spectral information using thermal infrared observations in the wavelength range from 4 to 50 micrometers.
"The L'TES team has used our experienced designing, manufacturing, and operating similar thermal emission spectrometers on other missions such as OSIRIS-REx and the Mars Global Surveyor as we built this instrument," said Instrument Principal Investigator, Phil Christensen. "Each instrument has its own challenges, but based on our experience we expect L'TES to give us excellent data, as well as likely some surprises, about these enigmatic objects."
Despite the challenges surrounding the COVID-19 pandemics, Lucy is on schedule to launch in October 2021 as originally planned.
"I am constantly impressed by the agility and flexibility of this team to handle any challenges set before them," said mission Principal Investigator, Hal Levison of Southwest Research Institute. "Just five years ago this mission was an idea on paper, and now we have many major components of the spacecraft and payload assembled, tested, and ready to go."
In addition to L'TES, Lucy's High Gain Antenna, which will enable spacecraft communication with the Earth for navigation and data collection, as well as precise measurement of the masses of the Trojan asteroids, was recently installed. It joined L'LORRI, Lucy's highest resolution camera, built by the Johns Hopkins Applied Physics Laboratory, which was installed in early November. Lucy's remaining scientific instrument, L'Ralph, the mission's color imaging camera and infrared spectrometer, is scheduled to be delivered in early 2021.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 08-02-2021 03:48 PM
Lockheed Martin release
NASA's Lucy Spacecraft Begins Launch Preparations
NASA's Lucy spacecraft has officially arrived at Kennedy Space Center, Florida, to begin preparations ahead of its launch this fall.
"This spacecraft is so much more than a piece of hardware, it's a work of art, and I'm incredibly proud of how the team came together to build this through a global pandemic," said Rich Lipe, Lockheed Martin Lucy program manager. "To be here now, starting to prepare for launch, is a terrific feeling."
Designed and built by Lockheed Martin for NASA, Lucy will give humankind its first ever close-up look at Jupiter's elusive Trojan asteroids. These celestial objects are important because scientists believe they could hold clues about how our solar system and the planets formed.
Shipping a Precious Package
In the pre-dawn hours Friday (July 30), Lucy took the first steps of its 12-year, four-billion-mile odyssey to the "fossils" of the solar system by boarding a cargo plane in Colorado.
And moving a nearly one-ton spacecraft 18 months in the making is no small feat.
After converting a shipping container into its own mini cleanroom environment, a team of Lockheed Martin engineers carefully placed Lucy inside and loaded the spacecraft onto a special transport truck at the company's Littleton, Colorado, facility.
Flanked by its own police escort, the truck made its way to Buckley Space Force Base in Aurora, Colorado, where a team of about 40 people from Lockheed Martin, NASA and Southwest Research Institute met Lucy and tucked the spacecraft safely inside its C-17 transport aircraft.
After touching down on the Space Shuttle Landing Strip at Kennedy Space Center, Lucy was moved to Astrotech Space Operations, where it will begin preparations for a 23-day launch window that opens Oct. 16.
What's Ahead in the Journey?
Following its pre-launch testing, launch vehicle integration and liftoff on an Atlas V 401 rocket, the path that lies ahead will see Lucy visit a record-breaking number of asteroids – eight, to be precise.
As part of a highly complex orbital trajectory, Lucy will fly by one Main Belt asteroid and seven Trojan asteroids – ancient objects trapped within gravity wells created by the combined pull of Jupiter and the sun, near so-called Lagrange Points. One group leads and one group trails Jupiter in its orbit.
The spacecraft will use precise instruments to study the geology, surface composition and physical properties of these primitive Trojan asteroids. Scientific theory hypothesizes these objects were scattered during the creation of our outer solar system roughly 4 billion years ago and later captured in Jupiter's orbit – remaining there, undisturbed, for billions of years.
These genuine "fossils" of the solar system could hold clues about what conditions were like when the planets formed, leading to an even greater understanding of our own origins.
Lucy's first asteroid flyby occurs in 2025, and the last planned flyby will be in 2033.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 10-14-2021 06:36 PM
United Launch Alliance (ULA) photo release
Atlas V with Lucy rolled out to launch pad
Rollout of the Atlas V rocket to launch Lucy got underway on Thursday (Oct. 14) with first motion at 10:37 a.m. EDT (1437 GMT) as the mobile launch platform departed the Complex 41 Vertical Integration Facility (VIF).
An hour later, the MLP was lowered onto the launch pad piers, accomplishing the "harddown" milestone at 11:35 a.m. EDT (1535 GMT). The Atlas V rocket with the Lucy spacecraft aboard stands 188 feet (57.3 meters) tall and will weigh 742,913 pounds (336,980 kg) at liftoff.
The seven-hour launch countdown will begin Friday night (Oct. 15), leading to a liftoff Saturday at 5:34 a.m. EDT (0934 GMT).
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
A NASA probe has embarked on a 12-year mission to visit a record number of small worlds, exploring for the first time a group of asteroids that may be the leftover remains from the creation of our solar system.
The spacecraft, named "Lucy," launched Saturday (Oct. 16) atop a United Launch Alliance (ULA) Atlas V rocket from Complex 41 at the Cape Canaveral Space Force Station in Florida. The 5:34 a.m. EDT (0934 GMT) liftoff began the mission's journey to the Trojans — two swarms of asteroids that lead and follow Jupiter in its orbit around the Sun.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 10-17-2021 04:37 PM
NASA release
Lucy Spacecraft Healthy; Solar Arrays Being Analyzed
Following a successful launch on Oct. 16, 2021, analysis of NASA's Lucy spacecraft systems show the spacecraft is operating well and is stable. Lucy's two solar arrays have deployed, and both are producing power and the battery is charging.
While one of the arrays has latched, indications are that the second array may not be fully latched. All other subsystems are normal. In the current spacecraft attitude, Lucy can continue to operate with no threat to its health and safety.
The team is analyzing spacecraft data to understand the situation and determine next steps to achieve full deployment of the solar array.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 10-19-2021 08:32 PM
NASA release
NASA Team Remains Focused on Lucy's Solar Arrays
After successful separation from the rocket on Oct. 16, NASA's Lucy spacecraft deployed both solar arrays. Soon after deployment, NASA received confirmation that one of the solar arrays was fully deployed and latched. Analysis currently shows the second solar array is partially unfurled. The team continues to look at all available engineering data to establish how far it is deployed. That solar array is generating nearly the expected power when compared to the fully deployed wing. This power level is enough to keep the spacecraft healthy and functioning.
The Lucy spacecraft has remained in safe mode and is transitioning to cruise mode today. This mode has increased autonomy and spacecraft configuration changes, which is necessary as Lucy moves away from Earth. The team continues its assessment and an attempt to fully deploy the solar array is planned no earlier than the end of next week.
Lucy has successfully fired thrusters to slew the spacecraft with the current array configuration and will safely continue with desaturation maneuvers — small thruster firings to manage the spacecraft's momentum — as planned.
The operations team has temporarily postponed the deployment of the instrument pointing platform to focus on resolving solar array deployment. The operations team continues to execute all other planned post-launch activities. The ULA Atlas V rocket delivered Lucy precisely to the target point at separation, and so a backup maneuver called the Trajectory Correction Maneuver (TCM-1) is unnecessary and has therefore been canceled. The first maneuver will now be what's known as TCM-2, currently scheduled for mid-December.
The project is evaluating whether there are any long-term implications to other scheduled activities.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 10-22-2021 04:49 PM
NASA release
Lucy Spacecraft Healthy as NASA Continues Solar Array Assessments
NASA's Lucy spacecraft successfully transitioned to cruise mode Oct. 20, which is the standard configuration for flight. The following day, the instrument pointing platform was deployed after temporarily being postponed earlier in the week. Both events were normal and raised no concerns. The spacecraft remains stable, power positive, with all other subsystems working, with the exception of one solar array.
The Lucy team is working to understand the current state of the array before attempting to complete deployment. NASA is reviewing spacecraft data, including using techniques to measure how much electric current is produced by the array during various spacecraft positions and attitudes. This will allow the team to understand how close the array is to the latched position. These techniques are well within the capabilities of the system and pose no risk. Any plans for re-deployment will be considered after completing this latest assessment.
The spacecraft continues to travel along its expected trajectory.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 10-27-2021 06:46 PM
NASA update
Lucy Stable in Cruise Mode
The Lucy spacecraft remains in cruise mode, which is the standard flight mode for outbound flight and allows for substantial autonomy for the spacecraft. The spacecraft has successfully executed several small planned maneuvers, which have had no adverse effect on the one solar array that is not fully deployed. On Oct. 29, NASA will adjust Lucy's position to point toward Earth in preparation for instrument checkout.
Most recently, the spacecraft's position was adjusted on Oct. 26 to allow the team to measure how much electric current is moving through the partially deployed solar array and thus understand how close that array is to the fully latched position. Analysis indicates that the array is between 75% and 95% deployed. It is currently being held in place by a lanyard, specifically designed to help unfurl the arrays during deployment.
An anomaly response team continues to work on establishing what caused the solar array to not fully deploy. NASA and SwRI are evaluating a range of options, including the possibility of leaving the array in its current state. Any attempt to safely redeploy the array would occur no earlier than Nov. 16.
All other systems are functioning normally.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 11-18-2021 01:44 PM
NASA update
Lucy Instruments Checkout A-OK
NASA's Lucy spacecraft continues to operate in cruise mode – the standard mode for its orbit away from Earth.
Checkouts for the Lucy instruments were successfully completed Nov. 8, and all instruments are working normally. Following checkout completion, the instruments were powered off, and the remaining spacecraft subsystem commissioning activities are continuing as scheduled.
Lucy's Solar Array Anomaly Response Team has made progress searching for the cause of the solar array's incomplete deployment. The team has used an engineering model of the solar array motor and lanyard to replicate what was observed during the initial solar array deployment. The test data and findings suggest the lanyard may not have wound on the spool as intended. Testing continues to determine what caused this outcome, and a range of scenarios are possible. The team isn't planning to attempt to move or further characterize the current state of the solar array deployment before Wednesday, Dec. 1, at the earliest.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 04-21-2022 06:31 PM
NASA release
NASA's Lucy Mission Is "Go" for Solar Array Deployment Attempt
On April 18, NASA decided to move forward with plans to complete the deployment of the Lucy spacecraft's stalled, unlatched solar array. The spacecraft is powered by two large arrays of solar cells that were designed to unfold and latch into place after launch. One of the fan-like arrays opened as planned, but the other stopped just short of completing this operation.
Through a combination of rigorous in-flight solar array characterization and ground testing, Lucy engineers determined the unlatched solar array is nearly fully open, positioned at approximately 345 out of the full 360 degrees, and is producing ample energy for the spacecraft. Nonetheless, the team is concerned about potential damage to the array if the spacecraft conducts a main engine burn in its present configuration.
After launch, the arrays were opened by a small motor that reels in a lanyard attached to both ends of the folded solar array. The team estimates that 20 to 40 inches of this lanyard (out of approximately 290 inches total) remains to be retracted for the open array to latch.
The solar array was designed with both a primary and a backup motor winding to give an added layer of reliability for the mission-critical solar array deployment. Lucy engineers will take advantage of this redundancy by using both motors simultaneously to generate higher torque than was used on the day of launch. Ground tests show that this added torque may be enough to pull the snarled lanyard the remaining distance needed to latch.
The team is now preparing to complete the solar array deployment in two steps. The first step, tentatively scheduled for the week of May 9, is intended to pull in most of the remaining lanyard and verify that flight results are consistent with ground testing. This step will also strengthen the array by bringing it closer to a fully tensioned state. Because this step is designed to be limited in duration, the array is not likely to latch at that point.
If this step goes as planned, the second step will continue the array deployment with the intent to fully latch. Information gleaned from the first part will help fine-tune the second. The second step is currently planned for a month after the initial one, giving engineers enough time to analyze the data seen in the first attempt.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 05-11-2022 02:28 PM
NASA release
Lucy team completes step one of the solar array deployment attempt
On May 9, NASA's Lucy team executed the first of two planned steps in its efforts to complete the deployment of the spacecraft's unlatched solar array.
This first step was time-limited and was intended to validate that the team's ground testing adequately represented the flight system's performance, rather than to latch the solar array.
Analysis is currently underway to determine if the results are consistent with ground testing. After reviewing the data, the team will determine the next steps for the deployment effort.
The second step is tentatively scheduled for about a month after the first one.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 08-04-2022 09:23 AM
NASA release
NASA Team Troubleshoots Asteroid-Bound Lucy Across Millions of Miles
Following the successful launch of NASA's Lucy spacecraft on Oct. 16, 2021, a group of engineers huddled around a long conference table in Titusville, Florida. Lucy was mere hours into its 12-year flight, but an unexpected challenge had surfaced for the first-ever Trojan asteroids mission.
Data indicated that one of Lucy's solar arrays powering the spacecraft's systems — designed to unfurl like a hand fan — hadn't fully opened and latched, and the team was figuring out what to do next.
Teams from NASA and Lucy mission partners quickly came together to troubleshoot. On the phone were team members at Lockheed Martin's Mission Support Area outside of Denver, who were in direct contact with the spacecraft.
The conversation was quiet, yet intense. At one end of the room, an engineer sat with furrowed brow, folding and unfolding a paper plate in the same manner that Lucy's huge circular solar arrays operate.
There were so many questions. What happened? Was the array open at all? Was there a way to fix it? Would Lucy be able to safely perform the maneuvers needed to accomplish its science mission without a fully deployed array?
With Lucy already speeding on its way through space, the stakes were high.
Within hours, NASA pulled together Lucy's anomaly response team, comprising members from science mission lead Southwest Research Institute (SwRI) in San Antonio; mission operations lead NASA's Goddard Space Flight Center in Greenbelt, Maryland; spacecraft builder Lockheed Martin; and Northrop Grumman in San Diego, solar array system designer and builder.
"This is a talented team, firmly committed to the success of Lucy," said Donya Douglas-Bradshaw, former Lucy project manager from NASA Goddard. "They have the same grit and dedication that got us to a successful launch during a once-in-a-lifetime pandemic."
United in their pursuit to ensure Lucy would reach its fullest potential, the team began an exhaustive deep dive to determine the cause of the issue and develop the best path forward.
Given that the spacecraft was otherwise perfectly healthy, the team wasn't rushing into anything.
"We have an incredibly talented team, but it was important to give them time to figure out what happened and how to move forward," said Hal Levison, Lucy's principal investigator from SwRI. "Fortunately, the spacecraft was where it was supposed to be, functioning nominally, and – most importantly – safe. We had time."
Staying focused during many long days and nights, the team worked through options. To evaluate Lucy's solar array configuration in real time, the team fired thrusters on the spacecraft and gathered data on how those forces made the solar array vibrate. Next, they fed the data into a detailed model of the array's motor assembly to infer how rigid Lucy's array was – which helped uncover the source of the issue.
At last, they closed in on the root cause: a lanyard designed to pull Lucy's massive solar array open was likely snarled on its bobbin-like spool.
After months of further brainstorming and testing, Lucy's team settled on two potential paths forward.
In one, they would pull harder on the lanyard by running the array's back-up deployment motor at the same time as its primary motor. The power from two motors should allow the jammed lanyard to wind in further and engage array's latching mechanism. While both motors were never originally intended to operate at the same time, the team used models to ensure the concept would work.
The second option: use the array as it was – nearly fully deployed and generating more than 90% of its expected power.
"Each path carried some element of risk to achieve the baseline science objectives," said Barry Noakes, Lockheed Martin's deep space exploration chief engineer. "A big part of our effort was identifying proactive actions that mitigate risk in either scenario."
The team mapped out and tested possible outcomes for both options. They analyzed hours of the array's test footage, constructed a ground-based replica of the array's motor assembly, and tested the replica past its limits to better understand risks of further deployment attempts. They also developed special, high-fidelity software to simulate Lucy in space and gauge any potential ripple effects a redeployment attempt could have on the spacecraft.
"The cooperation and teamwork with the mission partners was phenomenal," said Frank Bernas, vice president, space components and strategic businesses at Northrop Grumman.
After months of simulations and testing, NASA decided to move forward with the first option – a multi-step attempt to fully redeploy the solar array. On seven occasions in May and June, the team commanded the spacecraft to simultaneously run the primary and backup solar array deployment motors. The effort succeeded, pulling in the lanyard, and further opening and tensioning the array.
The mission now estimates that Lucy's solar array is between 353 degrees and 357 degrees open (out of 360 total degrees for a fully deployed array). While the array is not fully latched, it is under substantially more tension, making it stable enough for the spacecraft to operate as needed for mission operations.
The spacecraft is now ready and able to complete the next big mission milestone – an Earth-gravity assist in October 2022. Lucy is scheduled to arrive at its first asteroid target in 2025.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 10-14-2022 01:12 AM
NASA release
NASA's Lucy Spacecraft Prepares to Swing by Earth
On Oct. 16, at 7:04 a.m. EDT, NASA's Lucy spacecraft, the first mission to the Jupiter Trojan asteroids, will skim the Earth's atmosphere, passing a mere 220 miles (350 kilometers) above the surface. By sling-shotting past Earth on the first anniversary of its launch, Lucy will gain some of the orbital energy it needs to travel to this never-before-visited population of asteroids.
The Trojan asteroids are trapped in orbits around the Sun at the same distance as Jupiter, either far ahead of or behind the giant planet. Lucy is currently one year into a twelve-year voyage. This gravity assist will place Lucy on a new trajectory for a two-year orbit, at which time it will return to Earth for a second gravity assist. This second assist will give Lucy the energy it needs to cross the main asteroid belt, where it will observe asteroid Donaldjohanson, and then travel into the leading Trojan asteroid swarm. There, Lucy will fly past six Trojan asteroids: Eurybates and its satellite Queta, Polymele and its yet unnamed satellite, Leucus, and Orus. Lucy will then return to Earth for a third gravity assist in 2030 to re-target the spacecraft for a rendezvous with the Patroclus-Menoetius binary asteroid pair in the trailing Trojan asteroid swarm.
For this first gravity assist, Lucy will appear to approach Earth from the direction of the Sun. While this means that observers on Earth will not be able to see Lucy in the days before the event, Lucy will be able to take images of the nearly full Earth and Moon. Mission scientists will use these images to calibrate the instruments.
Lucy's trajectory will bring the spacecraft very close to Earth, lower even than the International Space Station, which means that Lucy will pass through a region full of earth-orbiting satellites and debris. To ensure the safety of the spacecraft, NASA developed procedures to anticipate any potential hazard and, if needed, to execute a small maneuver to avoid a collision.
"The Lucy team has prepared two different maneuvers," says Coralie Adam, Lucy deputy navigation team chief from KinetX Aerospace in Simi Valley, California. "If the team detects that Lucy is at risk of colliding with a satellite or piece of debris, then--12 hours before the closest approach to Earth --the spacecraft will execute one of these, altering the time of closest approach by either two or four seconds. This is a small correction, but it is enough to avoid a potentially catastrophic collision."
Lucy will be passing the Earth at such a low altitude that the team had to include the effect of atmospheric drag when designing this flyby. Lucy's large solar arrays increase this effect.
"In the original plan, Lucy was actually going to pass about 30 miles closer to the Earth," says Rich Burns, Lucy project manager at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "However, when it became clear that we might have to execute this flyby with one of the solar arrays unlatched, we chose to use a bit of our fuel reserves so that the spacecraft passes the Earth at a slightly higher altitude, reducing the disturbance from the atmospheric drag on the spacecraft's solar arrays."
At around 6:55 a.m. EDT, Lucy will first be visible to observers on the ground in Western Australia (6:55 p.m. for those observers). Lucy will quickly pass overhead, clearly visible to the naked eye for a few minutes before disappearing at 7:02 a.m. EDT as the spacecraft passes into the Earth's shadow. Lucy will continue over the Pacific Ocean in darkness and emerge from the Earth's shadow at 7:26 a.m. EDT. If the clouds cooperate, sky watchers in the western United States should be able to get a view of Lucy with the aid of binoculars.
"The last time we saw the spacecraft, it was being enclosed in the payload fairing in Florida," said Hal Levison, Lucy principal investigator at the Southwest Research Institute (SwRI) Boulder, Colorado office. "It is exciting that we will be able to stand here in Colorado and see the spacecraft again. And this time Lucy will be in the sky."
Lucy will then rapidly recede from the Earth's vicinity, passing by the Moon and taking a few more calibration images before continuing out into interplanetary space.
"I'm especially excited by the final few images that Lucy will take of the Moon," said John Spencer, acting deputy project scientist at SwRI. "Counting craters to understand the collisional history of the Trojan asteroids is key to the science that Lucy will carry out, and this will be the first opportunity to calibrate Lucy's ability to detect craters by comparing it to previous observations of the Moon by other space missions."
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 01-21-2023 10:58 AM
NASA release
NASA's Lucy Mission Suspending Further Solar Array Deployment Activities
NASA's Lucy mission team has decided to suspend further solar array deployment activities. The team determined that operating the mission with the solar array in the current unlatched state carries an acceptable level of risk and further deployment activities are unlikely to be beneficial at this time. The spacecraft continues to make progress along its planned trajectory.
Shortly after the spacecraft's Oct. 2021 launch, the mission team realized that one of Lucy's two solar arrays had not properly unfurled and latched. A series of activities in 2022 succeeded in further deploying the array, placing it into a tensioned, but unlatched, state. Using engineering models calibrated by spacecraft data, the team estimates that the solar array is over 98% deployed, and it is strong enough to withstand the stresses of Lucy's 12-year mission. The team's confidence in the stability of the solar array was affirmed by its behavior during the close flyby of the Earth on Oct. 16, 2022, when the spacecraft flew within 243 miles (392 km) of the Earth, through the Earth's upper atmosphere. The solar array is producing the expected level of power at the present solar range and is expected to have enough capability to perform the baseline mission with margin.
The team elected to suspend deployment attempts after the attempt on Dec. 13, 2022, produced only small movement in the solar array. Ground-based testing indicated that the deployment attempts were most productive while the spacecraft was warmer, closer to the Sun. As the spacecraft is currently 123 million miles (197 million km) from the Sun (1.3 times farther from the Sun than the Earth) and moving away at 20,000 mph (35,000 km/hr), the team does not expect further deployment attempts to be beneficial under present conditions.
Due to the energy boost that the spacecraft received during last October's Earth gravity assist, the spacecraft is now on an orbit which will take it over 315 million miles (500 million km) from the Sun before returning to Earth for a second Earth gravity assist on Dec. 12, 2024. Over the next year and a half, the team will continue to collect data on how the solar array behaves during flight. Most significantly, the team will observe how the array behaves during a maneuver in Feb. 2024, when the spacecraft operates its main engine for the first time. As the spacecraft warms up during its approach to Earth in the fall of 2024, the team will re-evaluate if additional steps to reduce risk will be needed.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 02-01-2023 01:24 PM
NASA release
NASA's Lucy Team Announces New Asteroid Target
NASA's Lucy spacecraft will add another asteroid encounter to its 4-billion-mile journey. On Nov. 1, 2023, Lucy will get a close-up view of a small main-belt asteroid to conduct an engineering test of the spacecraft's innovative asteroid-tracking navigation system.
Above: As the NASA Lucy spacecraft travels through the inner edge of the main asteroid belt in the Fall of 2023, the spacecraft will fly by the small, as-of-yet unnamed, asteroid (152830) 1999 VD57. This graphic shows a top-down view of the Solar System indicating the spacecraft's trajectory shortly before the November 1 encounter. (NASA's Goddard Space Flight Center)
The Lucy mission is already breaking records by planning to visit nine asteroids during its 12-year tour of the Jupiter Trojan asteroids, which orbit the Sun at the same distance as Jupiter. Originally, Lucy was not scheduled to get a close-up view of any asteroids until 2025, when it will fly by the main belt asteroid (52246) Donaldjohanson. However, the Lucy team identified a small, as-yet unnamed asteroid in the inner main belt, designated (152830) 1999 VD57, as a potential new and useful target for the Lucy spacecraft.
"There are millions of asteroids in the main asteroid belt," said Raphael Marschall, Lucy collaborator of the Nice Observatory in France, who identified asteroid 1999 VD57 as an object of special interest for Lucy. "I selected 500,000 asteroids with well-defined orbits to see if Lucy might be traveling close enough to get a good look at any of them, even from a distance. This asteroid really stood out. Lucy's trajectory as originally designed will take it within 40,000 miles of the asteroid, at least three times closer than the next closest asteroid."
The Lucy team realized that, by adding a small maneuver, the spacecraft would be able to get an even closer look at this asteroid. So, on Jan. 24, the team officially added it to Lucy's tour as an engineering test of the spacecraft's pioneering terminal tracking system. This new system solves a long-standing problem for flyby missions: during a spacecraft's approach to an asteroid, it is quite difficult to determine exactly how far the spacecraft is from the asteroid, and exactly which way to point the cameras.
"In the past, most flyby missions have accounted for this uncertainty by taking a lot of images of the region where the asteroid might be, meaning low efficiency and lots of images of blank space," said Hal Levison, Lucy principal investigator from the Southwest Research Institute Boulder, Colorado office. "Lucy will be the first flyby mission to employ this innovative and complex system to automatically track the asteroid during the encounter. This novel system will allow the team to take many more images of the target."
It turns out that 1999 VD57 provides an excellent opportunity to validate this never-before-flown procedure. The geometry of this encounter—particularly the angle that the spacecraft approaches the asteroid relative to the Sun—is very similar to the mission's planned Trojan asteroid encounters. This allows the team to carry out a dress rehearsal under similar conditions well in advance of the spacecraft's main scientific targets.
This asteroid was not identified as a target earlier because it is extremely small. In fact, 1999 VD57, estimated to be a mere 0.4 miles (700 m) in size, will be the smallest main belt asteroid ever visited by a spacecraft. It is much more similar in size to the near-Earth asteroids visited by recent NASA missions OSIRIS-REx and DART than to previously visited main belt asteroids.
The Lucy team will carry out a series of maneuvers starting in early May 2023 to place the spacecraft on a trajectory that will pass approximately 280 miles (450 km) from this small asteroid.
Robert Pearlman Editor
Posts: 51308 From: Houston, TX Registered: Nov 1999
posted 11-02-2023 05:03 PM
NASA release
NASA's Lucy Spacecraft Discovers 2nd Asteroid During Dinkinesh Flyby
On Nov. 1, NASA's Lucy spacecraft flew by not just its first asteroid, but its first two. The first images returned by Lucy reveal that the small main belt asteroid Dinkinesh is actually a binary pair.
Above: This image shows the "moonrise" of the satellite as it emerges from behind asteroid Dinkinesh as seen by the Lucy Long-Range Reconnaissance Imager (L'LORRI), one of the most detailed images returned by NASA's Lucy spacecraft during its flyby of the asteroid binary. This image was taken at 12:55 p.m. EDT (1655 UTC) Nov. 1, 2023, within a minute of closest approach, from a range of approximately 270 miles (430 km). From this perspective, the satellite is behind the primary asteroid. The image has been sharpened and processed to enhance contrast. (NASA/Goddard/SwRI/ASU)
"Dinkinesh really did live up to its name; this is marvelous," said Hal Levison, referring to the meaning of Dinkinesh in the Amharic language, "marvelous." Levison is principal investigator for Lucy from the Boulder, Colorado, branch of the San-Antonio-based Southwest Research Institute. "When Lucy was originally selected for flight, we planned to fly by seven asteroids. With the addition of Dinkinesh, two Trojan moons, and now this satellite, we've turned it up to 11."
In the weeks prior to the spacecraft's encounter with Dinkinesh, the Lucy team had wondered if Dinkinesh might be a binary system, given how Lucy's instruments were seeing the asteroid's brightness changing with time. The first images from the encounter removed all doubt. Dinkinesh is a close binary. From a preliminary analysis of the first available images, the team estimates that the larger body is approximately 0.5 miles (790 m) at its widest, while the smaller is about 0.15 miles (220 m) in size.
This encounter primarily served as an in-flight test of the spacecraft, specifically focusing on testing the system that allows Lucy to autonomously track an asteroid as it flies past at 10,000 mph, referred to as the terminal tracking system.
"This is an awesome series of images. They indicate that the terminal tracking system worked as intended, even when the universe presented us with a more difficult target than we expected," said Tom Kennedy, guidance and navigation engineer at Lockheed Martin in Littleton, Colorado. "It's one thing to simulate, test, and practice. It's another thing entirely to see it actually happen."
Above: A series of images of the binary asteroid pair, Dinkinesh, as seen by the terminal tracking camera (T2CAM) on NASA's Lucy spacecraft during its closest approach on Nov. 1, 2023. The images were taken 13 seconds apart. The apparent motion of the two asteroids is due to the motion of the spacecraft as it flew past at 10,000 mph (4.5 km/s). These images have been sharpened and processed to enhance contrast. (NASA/Goddard/SwRI/ASU)
While this encounter was carried out as an engineering test, the team's scientists are excitedly poring over the data to glean insights into the nature of small asteroids.
"We knew this was going to be the smallest main belt asteroid ever seen up close," said Keith Noll, Lucy project scientist from NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The fact that it is two makes it even more exciting. In some ways these asteroids look similar to the near-Earth asteroid binary Didymos and Dimorphos that DART saw, but there are some really interesting differences that we will be investigating."
It will take up to a week for the team to downlink the remainder of the encounter data from the spacecraft. The team will use this data to evaluate the spacecraft's behavior during the encounter and to prepare for the next close-up look at an asteroid, the main belt asteroid Donaldjohanson, in 2025. Lucy will then be well-prepared to encounter the mission's main targets, the Jupiter Trojan asteroids, starting in 2027.