Solar System 'Detectives' Search for Clues in 'Crumbs' Left Over from Early Solar System
NASA awarded nearly $3 million to the University of Arizona Kuiper Materials Imaging and Characterization Facility to support OSIRIS-REx sample science and much more.
By Mikayla Mace and Daniel Stolte, University Communications - January 25, 2023
A magnifying glass just won't cut it for the high-tech "detectives" at the University of Arizona Kuiper Materials Imaging and Characterization Facility. The scientists, who can be found in the basement of the university's Kuiper Space Sciences Building, are working to decode the stories archived in rocks and dust left over from the earliest days of the solar system.
The facility has been a resource for public and private science programs, both on and off campus, since 2016. Now, thanks to a four-year, nearly $3 million grant from NASA to support facility operations, scientists will be able to dig deeper into scientific questions than ever before.
"The history of the solar system is encoded in asteroids – the planetary crumbs left over from its birth over 4.5 billion years ago," said facility director Thomas Zega, a UArizona planetary sciences professor. "The university and NASA are both investing a lot of money and resources in bringing back a sample from Bennu, a carbonaceous asteroid, and this is the first asteroid sample return mission in NASA's history, so it's important that we're properly equipped as a science team to analyze the sample when it comes back."
Facility co-investigators include assistant professors of planetary sciences Jessica Barnes and Pierre Haenecour, as well as Regents Professor of Planetary Sciences Dante Lauretta, principal investigator of NASA's OSIRIS-REx mission, which will return a sample from asteroid Bennu to Earth later this year.
In addition to asteroid samples, scientists use the facility to analyze meteorites and debris from asteroids and other planetary bodies that fall to Earth. The facility has cutting-edge instrumentation and is open to users on campus as well as from other universities or the private sector. The new grant will allow researchers who already receive funding through NASA to use the fee-based facility at a reduced rate.
Other NASA programs that use the facility include the Interdisciplinary Consortia for Astrobiology Research, Laboratory Analysis of Returned Samples and Emerging Worlds. The facility will also serve research efforts on planetary materials returned by other space agencies' sample return missions, such as Japan's Hayabusa 2, which is OSIRIS-REx's "sister mission."
"There's even more sample science to look forward to in the future," Zega said.
For example, NASA's Artemis missions will return lunar samples. And UArizona researchers are pursuing funding for the Comet Astrobiology Exploration Sample Return, or CAESAR mission, which would return a sample from a comet.
"The U.S. has been a world leader in sample science, and we want to maintain that, especially here at the University of Arizona," said University of Arizona President Robert C. Robbins. "Extracting the maximum amount of scientific information from modest samples is no easy feat and requires high-tech instrumentation like we have on our campus. I am honored by NASA's continued faith in our expertise, and I look forward to what we will learn."
Scale is everything
The university-led OSIRIS-REx mission was designed to return 60 grams – a little over 2 ounces – of surface material from asteroid Bennu. The mission team estimates that it's collected quite a bit more than that, and the mission's science team members, who are spread all over the world, will be allotted 25% of the total mass collected. A fraction of the sample will be released to investigators who are not part of the OSIRIS-Rex science team, and the remainder will be curated for future generations of researchers.
"We want to be sure we can look at the samples at multiple scales, from something you can see in the palm of your hand, all the way down to the atomic level," Zega said. "To do this, we need extremely sophisticated instrumentation."
The Kuiper Materials Imaging and Characterization Facility includes a focused-ion-beam scanning electron microscope, transmission electron microscope, an electron microprobe laboratory and scanning electron microscopes. A NanoSIMS instrument for measuring chemical elements in a sample is scheduled to arrive in June.
"There are different types of analysis we have to do on samples, and most chemists who study planetary materials specialize in one or several measurement techniques," Zega said. "We all have different specialties, and together our expertise complements one another and rounds out the analytical portfolio that we wanted to build at the university."
The tools: From microscopes to atomic probes
The first in a line of sample probing tools is the light microscope, familiar to many and used for centuries. It helps scientists visualize samples several hundred nanometers to micrometers in size, about the scale of bacteria and cells.
"Visible light microscopes are not able to 'sniff out' the chemical makeup of a sample, but they provide us with images, which might reveal textures and some information on its microstructure," Zega said.
"It also might reveal areas in your sample that you may want to target further," he said. "It might give you a sense of spatial relationship, which might tell you a little bit of the story to start piecing together some history of the sample. But it's not until more sophisticated methods that you start getting more of the picture."
The scanning electron microscope, or SEM, and electron microprobe are used for analyzing samples at a slightly smaller scale. An electron microprobe, also known as an electron probe microanalyzer, is similar to a scanning electron microscope, but offers the added capability of revealing clues about the sample's chemical composition.
"The microprobe allows us to image and map out the chemical heterogeneity in a sample in two dimensions at the micrometer scale, less than half the length of an average-sized bacterial cell," Zega said. "The SEM can do the same thing, although not quite the same level of precision. Both can image and give us compositional information at the microscale, and both are critical in analysis of the sample from Bennu, for example, because that level of information will tell us where in the sample we might want to probe further using NanoSIMS or TEM."
The NanoSIMS instrument measures the chemical elements in a sample, which is important for understanding the origins of the material. Unlike the SEM or microprobe, the NanoSIMS can reveal the isotopic composition of a sample. Isotopes are different varieties of chemical elements.
"The isotopic composition of a planetary material can tell us something about its origins and history that the elemental information alone may not," Zega said. "The NanoSIMS also lets us measure trace elements, which are present in extremely small amounts, at the scale of tens of a nanometer."
The transmission electron microscope operates at the smallest scales, allowing scientists in Zega's lab to see individual atoms.
In 2021, Zega's team used the tool, combined with quantum mechanics, chemical thermodynamics and astrophysical modeling, to reconstruct the origin journey of a dust grain through the nascent solar system.
"Because humans were not around 4.6 billion years ago to witness all of this chemistry happening, we have to examine the leftovers and reverse engineer their origins," Zega said. "That is what these sophisticated analytical tools enable us to do."
Decades in the making
"Our meteoric record is incomplete," Zega said. "Those of us who study meteorites are at the mercy of what falls from the sky; we don't know exactly where they come from, so we try and piece it together."
In the early 2010s, Mike Drake, who served as OSIRIS-REx principal investigator until his passing in 2011, and Lauretta, the mission's current principal investigator, realized that the university needed to build up capabilities in sample science if it was going to take on the mission, according to Zega.
"These guys were visionaries; they knew that we needed a sample return mission, and that was a major catalyst for building out the facility," Zega said. "Since then, we have made an effort to hire the right faculty to lead the lab. This is the culmination of 20 years of that effort."
NSF: UArizona Again Ranks Among Top 20 Public Research Universities, No. 1 in Astronomy and Astrophysics
UArizona saw an increase of more than $9 million over its fiscal year 2020 total and retained its No. 1 ranking in astronomy and astrophysics expenditures.
NSF: UArizona Again Ranks Among Top 20 Public Research Universities, No. 1 in Astronomy and Astrophysics
By Nick Prevenas, University Communications - December 19, 2022
The University of Arizona is ranked once again among the nation's top public research universities, with $770 million in total research activity in fiscal year 2021, according to data released Thursday by the National Science Foundation.
The university also retained its No. 1 ranking in astronomy and astrophysics expenditures at more than $113 million – more than $40 million ahead of the No. 2-ranked university.
The NSF's Higher Education Research and Development survey annually ranks more than 900 colleges and universities and is considered the primary source of information on research and development expenditures at U.S. colleges and universities.
UArizona saw an increase of more than $9 million over its fiscal year 2020 total. The university's research and development expenditures rank No. 20 among public institutions and No. 36 overall. This ranking places UArizona in the top 4% of all U.S. universities ranked in this list, both public and private. UArizona has held the No. 1 ranking in astronomy and astrophysics expenditures each year since 1987.
"The University of Arizona is one of the world's premier academic research institutions, evidenced by our steady increase in research and development expenditures," said University of Arizona President Robert C. Robbins. "From exploring the deepest corners of our galaxy to our leadership in vitally important efforts surrounding hypersonic technology and the quantum internet, University of Arizona researchers are at the forefront of the world's most exciting scientific discoveries."
The HERD survey also ranked UArizona No. 4 among schools with high Hispanic enrollment. In 2018, the university earned the designation of Hispanic-Serving Institution from the U.S. Department of Education for its success in the enrollment of Hispanic students.
UArizona ranked No. 5 in NASA-funded activity and No. 6 in the physical sciences.
"Powered by the forward thinking approach and determined spirit of our faculty and researchers, the University of Arizona research enterprise saw continued growth in the 2021 fiscal year," said Elizabeth "Betsy" Cantwell, senior vice president for research and innovation. "Vacuuming rubble from the surface of an asteroid in mere seconds, establishing a one-of-a-kind Institute for Global Grand Challenges with partners in France, and designing extended reality experiences to simulate real-life discrimination within our Center for Digital Humanities are among our many successes this year – demonstrative not only of the breadth and depth of our research, but also of its significant impact on society."
The University of Arizona Health Sciences had $305 million in research activity in fiscal year 2021, according to the NSF. This marks the third consecutive year of increases for UArizona Health Sciences, which has five colleges and 16 centers and programs in Tucson, Phoenix and Gilbert, Arizona.
"Our year-over-year increases in research activity are a testament to the University of Arizona Health Sciences' commitment to investigate and solve critical health care problems," said Dr. Michael D. Dake, senior vice president for the University of Arizona Health Sciences. "Our research strengths in areas such as immunology and immunotherapies, cancer, neurodegenerative diseases, chronic pain and addiction, and precision health care and treatments have the potential to improve health and well-being not only for Arizonans, but also for people around the world by building healthier communities for all."
UArizona also ranked No. 60 globally and No. 37 in the U.S. in the first edition of Research.com's ranking of the world's top universities.
UArizona's best rankings in the NSF's Higher Education Research and Development survey came in the following categories:
- No. 1: Astronomy and astrophysics
- No. 4: High Hispanic enrollment
- No. 5: NASA-funded activity
- No. 6: Physical sciences
- No. 20: All public universities
- No. 36: All universities
The University of Arizona also earned top-50 placements in the following categories:
- No. 21: Biological and biomedical sciences
- No. 27: Geosciences, atmospheric sciences and ocean sciences
- No. 29: Department of Agriculture expenditures
- No. 29: Agricultural sciences, natural resources and conservation
- No. 35: National Science Foundation expenditures
- No. 35: Science and engineering fields
- No. 39: Life sciences
- No. 41: Social sciences
- No. 42: Chemistry
- No. 45: Computer and information sciences
- No. 50: Department of Health and Human Services expenditures
Research highlights
Some examples of UArizona research that made headlines and had significant impact in fiscal year 2021, between July 1, 2020 and June 30, 2021, include:
OSIRIS-REx spacecraft is headed home with asteroid sample
After nearly five years in space, the OSIRIS-REx spacecraft began its journey back to Earth with an abundance of rocks and dust from near-Earth asteroid Bennu.
UArizona hypersonic experts contributing to $100M consortium
Home to multiple high-speed wind tunnels and facilities for high-temperature materials and manufacturing, UArizona is among the leading institutions working to accelerate research and technology for hypersonic flight.
UArizona partners with French National Centre for Scientific Research to establish France-Arizona Institute for Global Grand Challenges
The University of Arizona and the French National Centre for Scientific Research signed a research collaboration agreement to establish a new international research center focused on the environment, space science, data science and global climate change.
Sixth mirror casting brings Giant Magellan Telescope closer to completion
Underneath the stands of the Arizona Wildcats Football Stadium, engineers from the UArizona Richard F. Caris Mirror Lab manufacture the world's largest and most lightweight telescope mirrors. This year, they began casting the sixth of seven segments that together will make up the primary mirror of the Giant Magellan Telescope.
University of Arizona awarded $26M to architect the quantum internet
The University of Arizona is leading a new National Science Foundation Engineering Research Center, called the Center for Quantum Networks, with core partners Harvard, MIT and Yale.
Study shows SARS-CoV-2 antibodies provide lasting immunity
UArizona Heath Sciences researchers developed one of the most accurate COVID-19 antibody tests available and now have shown antibodies persist for months after infection, providing long-term immunity.
In partnership with UArizona, new nonprofit to launch satellite program to track greenhouse gas emissions
Carbon Mapper, a nonprofit organization partnering with UArizona, announced a groundbreaking program to help improve understanding of and accelerate reductions in global methane and carbon dioxide emissions.
UArizona to lead mission to discover potentially dangerous asteroids
A new mission to find, track and characterize asteroids and comets that may pose a threat to Earth moved one step closer to launch. The Near-Earth Object Surveyor mission – led by Amy Mainzer, a professor in the UArizona Lunar and Planetary Laboratory – was approved by NASA to begin its preliminary design phase.
Engineers propose solar-powered lunar ark as 'global insurance policy'
University of Arizona researcher Jekan Thanga is taking scientific inspiration from an unlikely source: the biblical tale of Noah's Ark. Rather than two of every animal, however, his solar-powered ark on the moon would store cryogenically frozen seed, spore, sperm and egg samples from 6.7 million Earth species.
Anti-racism project uses virtual reality to let people 'walk in someone else's shoes'
Bryan Carter, director of the UArizona Center for Digital Humanities, launched a project that uses virtual and augmented reality to re-create common experiences of racism and discrimination. The goal is to help people better understand those experiences by allowing them to "step into the shoes of others."
Einstein's description of gravity just got much harder to beat
Einstein's general theory of relativity – the idea that gravity is matter warping spacetime – has withstood over 100 years of scrutiny and testing, including the newest test by astrophysicists from the Event Horizon Telescope collaboration. According to their findings, Einstein's theory just got 500 times harder to beat.
How cold was the Ice Age?
Researchers now know A UArizona-led team nailed down the temperature of the last ice age – the Last Glacial Maximum of 20,000 years ago – to about 46 degrees Fahrenheit.
Giant Mantle Plume Reveals Mars is More Active than Previously Thought
Orbital observations unveil the presence of an enormous mantle plume pushing the surface of Mars upward and driving intense volcanic and seismic activity.
By Daniel Stolte, University Communications - December 5, 2022
On Earth, shifting tectonic plates reshuffle the planet’s surface and make for a dynamic interior, so the absence of such processes on Mars led many to think of it as a dead planet, where not much happened in the past 3 billion years.
In a study published in Nature Astronomy, scientists from the University of Arizona challenge current views of Martian geodynamic evolution with a report on the discovery of an active mantle plume pushing the surface upward and causing earthquakes and volcanic eruptions. The finding suggests that the planet’s deceptively quiet surface may hide a more tumultuous interior than previously thought.
"Our study presents multiple lines of evidence that reveal the presence of a giant active mantle plume on present-day Mars," said Adrien Broquet, a postdoctoral research associate in the UArizona Lunar and Planetary Laboratory and co-author of the study with Jeff Andrews-Hanna, an associate professor of planetary science at the LPL.
Mantle plumes are large blobs of warm and buoyant rock that rise from deep inside a planet and push through its intermediate layer – the mantle – to reach the base of its crust, causing earthquakes, faulting and volcanic eruptions. The island chain of Hawaii, for example, formed as the Pacific plate slowly drifted over a mantle plume.
"We have strong evidence for mantle plumes being active on Earth and Venus, but this isn't expected on a small and supposedly cold world like Mars," Andrews-Hanna said. "Mars was most active 3 to 4 billion years ago, and the prevailing view is that the planet is essentially dead today."
"A tremendous amount of volcanic activity early in the planet's history built the tallest volcanoes in the solar system and blanketed most of the northern hemisphere in volcanic deposits," Broquet said. "What little activity has occurred in recent history is typically attributed to passive processes on a cooling planet."
The researchers were drawn to a surprising amount of activity in an otherwise nondescript region of Mars called Elysium Planitia, a plain within Mars' northern lowlands close to the equator. Unlike other volcanic regions on Mars, which haven't seen major activity for billions of years, Elysium Planitia experienced large eruptions over the past 200 million years.
"Previous work by our group found evidence in Elysium Planitia for the youngest volcanic eruption known on Mars," Andrews-Hanna said. "It created a small explosion of volcanic ash around 53,000 years ago, which in geologic time is essentially yesterday."
Volcanism at Elysium Planitia originates from the Cerberus Fossae, a set of young fissures that stretch for more than 800 miles across the Martian surface. Recently, NASA’s InSight team found that nearly all Martian quakes, or marsquakes, emanate from this one region. Although this young volcanic and tectonic activity had been documented, the underlying cause remained unknown.
On Earth, volcanism and earthquakes tend to be associated with either mantle plumes or plate tectonics, the global cycle of drifting continents that continually recycles the crust.
"We know that Mars does not have plate tectonics, so we investigated whether the activity we see in the Cerberus Fossae region could be the result of a mantle plume," Broquet said.
Mantle plumes, which can be viewed as analogous to hot blobs of wax rising in lava lamps. give away their presence on Earth through a classical sequence of events. Warm plume material pushes against the surface, uplifting and stretching the crust. Molten rock from the plume then erupts as flood basalts that create vast volcanic plains.
When the team studied the features of Elysium Planitia, they found evidence of the same sequence of events on Mars. The surface has been uplifted by more than a mile, making it one of the highest regions in Mars’ vast northern lowlands. Analyses of subtle variations in the gravity field indicated that this uplift is supported from deep within the planet, consistent with the presence of a mantle plume.
Other measurements showed that the floor of impact craters is tilted in the direction of the plume, further supporting the idea that something pushed the surface up after the craters formed. Finally, when researchers applied a tectonic model to the area, they found that the presence of a giant plume, 2,500 miles wide, was the only way to explain the extension responsible for forming the Cerberus Fossae.
"In terms of what you expect to see with an active mantle plume, Elysium Planitia is checking all the right boxes," Broquet said, adding that the finding poses a challenge for models used by planetary scientists to study the thermal evolution of planets. "This mantle plume has affected an area of Mars roughly equivalent to that of the continental United States. Future studies will have to find a way to account for a very large mantle plume that wasn't expected to be there.
"We used to think that InSight landed in one of the most geologically boring regions on Mars – a nice flat surface that should be roughly representative of the planet’s lowlands," Broquet added. "Instead, our study demonstrates that InSight landed right on top of an active plume head."
The presence of an active plume will affect interpretations of the seismic data recorded by InSight, which must now take into account the fact that this region is far from normal for Mars.
"Having an active mantle plume on Mars today is a paradigm shift for our understanding of the planet’s geologic evolution," Broquet said, "similar to when analyses of seismic measurements recorded during the Apollo era demonstrated the moon's core to be molten."
Their findings could also have implications for life on Mars, the authors say. The studied region experienced floods of liquid water in its recent geologic past, though the cause has remained a mystery. The same heat from the plume that is fueling ongoing volcanic and seismic activity could also melt ice to make the floods – and drive chemical reactions that could sustain life deep underground.
"Microbes on Earth flourish in environments like this, and that could be true on Mars, as well," Andrews-Hanna said, adding that the discovery goes beyond explaining the enigmatic seismic activity and resurgence in volcanic activity. "Knowing that there is an active giant mantle plume underneath the Martian surface raises important questions regarding how the planet has evolved over time. "We're convinced that the future has more surprises in store."
UArizona Scientists Thrilled by Unprecedented 'Portrait' of an Alien World
Thanks to the James Webb Space Telescope, scientists have identified a "mystery molecule" that previously stumped astronomers. They've also gained insights needed to interpret potential signs of habitability on other exoplanets.
By Daniel Stolte, University Communications - November 22, 2022
Leveraging the power of an imaging instrument built at the University of Arizona, NASA's James Webb Space Telescope has given astronomers the first view of an exoplanet's atmosphere in unprecedented detail.
A suite of discoveries to be published in five scientific papers provides a complete molecular and chemical profile of the sky surrounding WASP-39b, a so-called hot Saturn. The planet is about as massive as Saturn but is closer to its star, which is 700 light-years away, than Mercury, the innermost planet of our solar system, is to the sun.
UArizona scientists contributed substantially to the findings, which are based on data collected with JWST's Near-Infrared Camera, or NIRCam, which was designed by a team led by Marcia Rieke, a Regents Professor in the UArizona Steward Observatory.
While JWST and other space telescopes, including NASA's Hubble and Spitzer, previously revealed isolated ingredients of this broiling planet's atmosphere, the new readings from JWST provide a full menu of atoms, molecules, and even signs of active chemistry and clouds, according to a NASA news release.
In one of the "most exciting discoveries," the team reports that it was able to identify and pin down a molecule in the planet's atmosphere that showed up in previous observations but whose identity remained a mystery until now.
"We've now identified that molecule as sulfur dioxide," said Megan Mansfield, a NASA Sagan Fellow at Steward Observatory. "What's even more exciting is that in order for this molecule to be detected as clearly as it was, we think there must have been some photochemistry going on in the atmosphere, which has never been observed in a planet outside of our solar system."
Photochemistry – the process by which energetic starlight initiates chemical reactions that alter a planet's atmosphere – is fundamental for life on Earth, the scientists say. Photochemistry is responsible for maintaining the protective ozone layer in the Earth's upper atmosphere, helps plants and algae grow and allows humans to produce vitamin D in their skin.
Among the major contributors on the UArizona team were Sarah Moran, a postdoctoral research fellow at the UArizona Lunar and Planetary Lab who developed theoretical models of exoplanet atmospheres, and observer Everett Schlawin, an assistant research professor at Steward.
The modeling work by Moran and others led to another first: Scientists needed to apply computer models of photochemical processes to fully explain the data. The resulting improvements in modeling will help build the technological know-how to interpret potential signs of habitability on other exoplanets in the future. The resulting improvements in modeling will help build the technological know-how needed to interpret potential signs of habitability, including on worlds that have yet to be discovered.
To see light from WASP-39b, JWST tracked the planet as it passed in front of its star, allowing some of the star's light to filter through the planet's atmosphere. Different types of chemicals in the atmosphere absorb different colors of the starlight spectrum, so the colors that are missing tell astronomers which molecules are present. By viewing the universe in infrared light, JWST can pick up chemical fingerprints that can't be detected in visible light.
In addition to the "mystery molecule," the instruments on JWST also detected sodium, potassium, water, carbon dioxide and carbon monoxide in the atmosphere of WASP-39b, Moran said.
The team also found evidence of clouds in the exoplanet's atmosphere.
"We learn that the cloud deck on WASP-39b is not one uniform blanket but has more complex meteorological patterns, similar to the bands of clouds we see on planets in our solar system," Moran said.
The findings bode well for the capability of JWST's instruments to conduct a broad range of investigations of all types of exoplanets, including probing the atmospheres of smaller, rocky planets like those in the TRAPPIST-1 system, which consists of seven potentially Earthlike planets around a single star.
"Our collective effort verified that JWST works incredibly well to measure new molecules in atmospheres and find new mysteries, which is incredibly invigorating," Mansfield said. "NIRSpec (Near Infrared Spectograph), NIRCam, and NIRISS (Near Infrared Imager and Slitless Spectrograph) meet or even exceed expectations for transmission spectroscopy of exoplanets."
Catalina Sky Survey Predicted Impact of Small Asteroid Over Ontario, Canada
NASA Communications
NASA Communications - November 22, 2022
In the early hours of Saturday, Nov. 19, the skies over southern Ontario, Canada, lit up as a tiny asteroid harmlessly streaked across the sky high in Earth’s atmosphere, broke up, and likely scattered small meteorites over the southern coastline of Lake Ontario. The fireball wasn’t a surprise. Roughly 1 meter (3 feet) wide, the asteroid was detected 3 ½ hours before impact, making this event the sixth time in history a small asteroid has been tracked in space before impacting Earth’s atmosphere.
NASA is tasked with the detection and tracking of much larger near-Earth objects that could survive passage through Earth’s atmosphere and cause damage on the ground, but those objects can also be detected much further in advance than small ones like the asteroid that disintegrated over southern Ontario. Such small asteroids are not a hazard to Earth, but they can be a useful test for NASA’s planetary defense capabilities for discovery, tracking, orbit determination, and impact prediction.
“The planetary defense community really demonstrated their skill and readiness with their response to this short-warning event,” said Kelly Fast, Near-Earth Object Observations program manager for the Planetary Defense Coordination Office (PDCO) at NASA Headquarters in Washington. “Such harmless impacts become spontaneous real-world exercises and give us confidence that NASA’s planetary defense systems are capable of informing the response to the potential for a serious impact by a larger object.”
The asteroid was discovered NASA-funded Catalina Sky Survey, which is headquartered at the Lunar and Planetary Laboratory at the University of Arizona in Tucson, on the evening of Nov. 18 during routine search operations for near-Earth objects. The observations were quickly reported to the Minor Planet Center (MPC) – the internationally recognized clearinghouse for the position measurements of small celestial bodies – and the data was then automatically posted to the Near-Earth Object Confirmation Page.
NASA’s Scout impact hazard assessment system, which is maintained by the Center for Near Earth Object Studies (CNEOS) at the agency’s Jet Propulsion Laboratory in Southern California, automatically fetched the new data from that page and began calculating the object’s possible trajectory and chances of impact. CNEOS calculates every known near-Earth asteroid orbit to provide assessments of potential impact hazards in support of NASA’s PDCO.
Seven minutes after the asteroid was posted on the confirmation page, Scout had determined it had a 25% probability of hitting Earth’s atmosphere, with possible impact locations stretching from the Atlantic Ocean off the East Coast of North America to Mexico. More observations were then provided by the astronomical community, including amateur astronomers in Kansas, to better refine the asteroid’s trajectory and possible impact location.
“Small objects such as this one can only be detected when they are very close to Earth, so if they are headed for an impact, time is of the essence to collect as many observations as possible,” said Shantanu Naidu, navigation engineer and Scout operator at JPL. “This object was discovered early enough that the planetary defense community could provide more observations, which Scout then used to confirm the impact and predict where and when the asteroid was going to hit.”
As Catalina continued to track the asteroid over the next few hours, Scout used this new data to continually update the asteroid’s trajectory and the system’s assessment of the chance of impact, posting those results on the hazard-assessment system’s webpage.
Community Effort
Many astronomers check the Scout webpage throughout the night to determine the most important asteroids to track. A group of amateur astronomers at Farpoint Observatory in Eskridge, Kansas, tracked the asteroid for more than an hour, providing critical additional data that enabled Scout to confirm a 100% impact probability and determine the expected location of atmospheric entry as being over southern Ontario at 3:27 a.m. EST (12:27 a.m. PST) Nov. 19. With more than two hours remaining before impact, there was time to alert scientists in southwestern Ontario of the bright fireball that would occur.
A total of 46 observations of the asteroid’s position were ultimately collected, the final one being made only 32 minutes before impact by the University of Hawaii 88-inch (2.2-meter) telescope on Mauna Kea.
As predicted, at 3:27 a.m. EST (12:27 a.m. PST), the asteroid streaked through Earth’s atmosphere at a shallow angle and broke up, likely producing a shower of small meteorites and leaving no reported damage on the surface. After this harmless disintegration, the Minor Planet Center designated the asteroid 2022 WJ1 to acknowledge its discovery while still in space.
Dozens of sightings were reported to the American Meteor Society, and scientists who were alerted to the Scout prediction were able to photograph the asteroid’s atmospheric entry. Videos of the fireball collected by the public were also posted online. NASA’s Meteorite Falls website also reported weather radar detections of fragments of the fireball falling as meteorites at the predicted time over Lake Ontario. Small meteorites might be found east of the town of Grimsby while larger meteorites might be nearer the town of McNab.
The first asteroid to be discovered and tracked well before hitting Earth was 2008 TC3, which entered the atmosphere over Sudan and broke up in October 2008. That 13-foot-wide (4-meter-sized) asteroid scattered hundreds of small meteorites over the Nubian Desert. Earlier this year, asteroid 2022 EB5 entered the atmosphere over the Norwegian Sea after Scout accurately predicted its location, becoming the fifth object to be detected before impact. As surveys become more sophisticated and sensitive, more of these harmless objects are being detected before entering the atmosphere, providing real exercises for NASA’s planetary defense program.
Mapping Rock Glaciers to Understand Their Future on Earth and Mars
University of Arizona researchers developed a new method for analyzing rock glaciers, which could help scientists better understand these "hidden giants" on Earth and Mars.
By Mikayla Mace Kelley, University Communications - November 16, 2022
Standing on a rock glacier is what Tyler Meng imagines it would be like to stand on the surface of Mars. The glacier's barren and wrinkled landscape looks like Silly Putty that's drooped under gravity's pull, offering few clues that a frozen, debris-laden giant lurks beneath the surface.
Rock glaciers are so named because unlike pure ice glaciers, they are a mix of frozen water, sand and rocks. They are generally found at the base of steep mountainsides or cliffs that have slowly dropped rock debris, which then mixes with glacier ice and refrozen snowmelt. Rock glaciers also exist on Mars.
Meng – who is pursuing a doctoral degree in planetary science at the University of Arizona, with a minor in geosciences – is lead author of a study in the Journal of Glaciology that describes a new method to determine rock glaciers' ice thickness and the ratio of ice to debris, allowing for more precise measurements of these glaciers than previously possible. Meng and his adviser and co-author Jack Holt, a UArizona planetary sciences and geosciences professor, used this information to create maps of four rock glaciers in Colorado, Wyoming and Alaska.
Their work, and future work that uses this method, will allow scientists to better understand water resources on both Earth and Mars, as well as how resilient this type of buried ice will be to the changing climate on both planets.
More than ice
Rock glaciers are hidden and insulated by debris on top of ice, and their movement is affected by the rocks trapped inside of them.
"You can think of the rocks like an insulating blanket," Meng said. "Beyond a certain thickness, insulation basically turns off the melting, allowing for the ice to be preserved and slowly move or flow down a valley at elevations and temperatures where clean ice may be completely melted."
Both pure ice glaciers and rock glaciers can move across landscapes – very slowly. However, the debris in rock glaciers causes them to flow even more slowly than ice glaciers, as the inclusion of rocks makes them much stiffer. They're also typically smaller and thinner than clean ice glaciers, measuring just a couple miles in length, a few hundred or thousand feet wide and between 50 and 200 feet thick. Ice glaciers, in contrast, can be many miles in length and thousands of feet thick.
To collect the information needed to map and characterize these hidden giants, Meng, Holt, other UArizona students and their collaborators hiked rugged mountain terrain in the western U.S., lugging computers, battery packs and radar antennas on their backs. They navigated steep landscapes with loose rocks ranging in size from grains of sand to houses.
"Standing on a debris-covered glacier is pretty surreal, because it's in this barren area on a mountainside, and each rock glacier seems to have its own personality," Meng said. "They each have a slightly different type of bedrock supplying debris, and the valley geometry dictates its shape and appearance."
Using two different antenna configurations, the researchers used ground-penetrating radar to measure both the radar wave speed and the angle at which the wave was reflected from the subsurface. In the same way that humans have two eyes to see in three dimensions, two antenna configurations allowed the researchers to better calculate the dimensions of the rock glacier. They also estimated the ratio of ice to rock at each survey location using radar wave velocity.
"In the process, we made the most precise estimates of rock glacier geometry and composition to date," Meng said.
From Earth to Mars
Understanding rock glaciers on Earth is important because they are essentially water reservoirs, Meng said.
"Our research gives us a better idea of the total water budget in mountainous regions, where major rivers have headwaters," he said. "Snow is a year-to-year accumulation that covers an entire landscape, whereas rock glaciers are a more localized but permanent water reservoir that actually stores water for what could be hundreds to a few thousand years."
The researchers are continuing their analysis to understand signs of past climate change in rock glaciers and how these glaciers might have evolved through past climate changes.
"By having a map of the debris thickness and ice concentration, we can essentially characterize the ability of rock glaciers to withstand effects of a warming climate compared to clean ice glaciers," Meng said.
Other scientists also recognized rock glaciers on Mars by their wrinkled putty-like flow pattern, even before radar data detected them.
Martian rock glaciers are still not well understood, Meng said, but it is known that they are typically found between 30 and 60 degrees latitude in both of the planet's hemispheres and are much older than the Martian polar ice.
"These Martian rock glaciers are potential targets for water resources on Mars, too, because they're actually really large compared to the ones on Earth, like hundreds of meters thick," Meng said. "They're also more accessible than polar ice because spacecraft wouldn't have to change their orbits as much as they would if they were to land on a pole, which requires a lot more fuel to reach."
One of the big challenges for scientists is determining the thickness of the surface rock covering the glaciers on Mars. If there is 30 feet of rock and debris on rugged Martian terrain, then it might not be worth the trouble for astronauts to attempt to access the ice for water resources, Meng said.
"Our goal is to use these rock glaciers on Earth as an analog for processes on Mars," Meng said. "By mapping the patterns of debris thickness on Earth, we're trying to understand how that debris thickness may also vary on Mars. Also, by learning about the differences in flow parameters between clean ice and debris-rich ice, that will help simulations for the Martian case as well."
Moving forward, Holt's research group is continuing to make similar measurements using surface-based radar while collecting new data using drones. This drone-based data collection will help the group to gain a more complete understanding of rock glacier flow and subsurface characteristics, while also testing new geophysical methods that may be used in future exploration of Earth and Mars.
Planetary Scientist Dani DellaGiustina Makes Popular Science Brilliant 10
University of Arizona planetary scientist Dani DellaGiustina was chosen because of her work to understand the past and future of the solar system by studying asteroids. Her work also includes exploring the mysterious interiors of other worlds.
By Mikayla Mace Kelley, University Communications - October 19, 2022
The University of Arizona's Daniella "Dani" DellaGiustina shot for the stars and has already landed among them. Today, the planetary scientist was named one of Popular Science's Brilliant 10 – an annual list of early-career scientists and engineers who are developing innovative approaches to problems across a range of disciplines.
DellaGiustina is an assistant professor of planetary sciences in the university's Lunar and Planetary Laboratory and deputy principal investigator of NASA's UArizona-led OSIRIS-REx asteroid sample return mission. She is also principal investigator of the extended OSIRIS-REx mission, dubbed OSIRIS-APEX, which will visit the near-Earth asteroid Apophis.
DellaGiustina was chosen from hundreds of researchers across a variety of institutions.
Popular Science says its list aims to recognize the hard work, creativity and potential of those who are shaking up old modes of thinking, defining new disciplines and laying the groundwork for tomorrow's most groundbreaking research.
"For the Brilliant 10, we look for innovative thinkers and leaders whose work stands to reshape our understanding of our world. The insights Daniella's work will glean from asteroids will do just that," said Popular Science Editor-in-Chief Corinne Iozzio. "When Apophis makes its loop around Earth in 2029, the work she's prepping now will ensure we learn everything we can about our past, present and future as we possibly can."
"Dr. DellaGiustina is a brilliant planetary scientist whose work on the OSIRIS-REx and OSIRIS-APEX missions is expanding our knowledge of the makeup of asteroids and is laying the foundation for groundbreaking discoveries about the evolution of our solar system," said Carmala Garzione, dean of the College of Science. "Her journey through her education and career is inspirational and will support the next generation of female and Latina scientists. We are proud to have Dr. DellaGiustina representing our science community in Southern Arizona."
DellaGiustina is interested in water distribution throughout the solar system and how scientists can establish water's presence on different planetary bodies.
"Over the last year, I've been enamored with the scientific questions to establish how water got to the early Earth billions of years ago," DellaGiustina said. "I'm also interested in understanding the interiors of asteroids, moons and planets, because it's so difficult to do. We only have indirect measurements and techniques at our disposal, so we must pair those measurements with good assumptions to fully interpret the data. I enjoy that challenge."
DellaGiustina develops and deploys remote-sensing instruments to learn more about the surface and interior structure of small airless worlds, including asteroids and the moons of the outer solar system, where liquid oceans could be lurking beneath ice sheets.
She tests her technology in places like Greenland, which has a landscape similar to the planetary bodies she studies. Over the summer, she spent several weeks testing instruments at a lake beneath a glacier in northwest Greenland, where half a mile of ice overlays about 30 feet of salty water, providing a similar landscape to what is expected on Jupiter's moon Europa.
Following the water has also taken her to asteroid Bennu, from which the OSIRIS-REx spacecraft collected a sample in 2020 that will be returned to Earth in 2023. Bennu contained evidence of water in its past, and so drew scientific attention. After the OSIRIS-REx spacecraft jettisons its sample return capsule over the Utah desert in September 2023, the spacecraft will fly on to study Apophis, thanks to a $200 million mission extension by NASA that DellaGiustina will lead. The goal of the OSIRIS-APEX extended mission is to understand what lies just beneath the surface of asteroid Apophis. Researchers also want to understand how Apophis will be physically affected by the gravitational pull of Earth when the asteroid make a close approach to the planet in 2029.
DellaGiustina, 36, has rocketed from student to principal investigator in a short period of time. She said that what motivates her is her love of discovery.
"I get obsessed with scientific questions and like treating them like giant puzzles," DellaGiustina said. "I also just love being the first person to see the first image of a planetary surface, or the first to discover what is at the base of an ice sheet. I'm hooked on that feeling."
DellaGiustina earned a bachelor's degree in physics from the University of Arizona in 2008. She got her master's in computational physics from the University of Alaska in 2011 and then returned to UArizona, where she completed a doctorate in geosciences in 2021.
Her career began to bud at the UArizona Lunar and Planetary Laboratory when she an undergraduate in the Arizona Space Grant program, studying meteorites with professor Dante Lauretta, who would become principal investigator for OSIRIS-REx.
Her work led to a student experiment on the Phase A Discovery OSIRIS Mission, which was a precursor to OSIRIS-REx that ultimately was not selected by NASA for spaceflight but paved the way for the OSIRIS-REx mission. She developed an experiment to measure the ability of asteroids to provide radiation shielding for future manned missions to Mars.
In graduate school, DellaGiustina combined remote observations of Earth's ice sheets with modeling techniques to understand how ice flow will respond to a changing climate. She now uses her knowledge of Earth's permanently frozen regions to perform field studies in Earth landscapes similar to icy bodies in the solar system.
In 2012, DellaGiustina became a research scientist in the UArizona Department of Physics, and she transitioned back to planetary sciences in early 2014. She led the OSIRIS-REx image processing team from 2015 to 2021 before becoming deputy principal investigator of the mission in 2021. In addition to her other roles, she teaches a course about asteroids and comets to undergraduate and graduate students.
"Being recognized as one of the Brilliant 10 is really rewarding because I am a Latina who has not taken a traditional path through my career," DellaGiustina said.
She put the pursuit of her doctoral degree on the backburner while she worked for a while to figure out exactly what she wanted to study — eventually settling on seismology. She finished her doctorate while working full time as a scientist, graduating the same semester she wrote the proposal that would lead to her appointment as the OSIRIS-APEX principal investigator. At the same time, she was growing a spaceflight seismometer instrument program at UArizona, called the Seismometer to Investigate Ice and Ocean Structure. The program develops instruments needed to support missions to icy bodies in the outer solar system that could provide a sneak peek into the interiors of other worlds.
"It's been a little bit of a gamble to do things in the way I have," DellaGiustina said, "so it's nice to get external recognition that the work I'm doing is impactful."
Daniella DellaGiustina Named One of the "Brilliant 10" by Popular Science
Assistant Professor Daniella DellaGiustina is named one of the "Brilliant 10 2022" by Popular Science Magazine.
Scientists Identify Potential Source of 'Shock-darkened' Meteorites, with Implications for Hazardous Asteroid Deflection
University of Arizona planetary scientists identified a potential source of a special kind of meteorite. Its characteristics could explain certain discrepancies in how near-Earth asteroids are classified.
Scientists Identify Potential Source of 'Shock-darkened' Meteorites, with Implications for Hazardous Asteroid Deflection
By Mikayla Mace Kelley, University Communications - October 4, 2022
When the Chelyabinsk fireball exploded across Russian skies in 2013, it littered Earth with a relatively uncommon type of meteorite. What makes the Chelyabinsk meteorites and others like them special is their dark veins, created by a process called shock darkening. Yet, planetary scientists have been unable to pinpoint a nearby asteroid source of these kinds of meteorites – until now.
In a new paper published in the Planetary Science Journal, University of Arizona scientists identified an asteroid named 1998 OR2 as one potential source of shock-darkened meteorites. The near-Earth asteroid is about 1 1/2 miles wide and made a close approach to Earth in April 2020. When pieces of asteroids break off into space and then land on Earth, they are considered meteorites.
"Shock darkening is an alteration process caused when something impacts a planetary body hard enough that the temperatures partially or fully melt those rocks and alter their appearance both to the human eye and in our data," said lead study author Adam Battle, a UArizona graduate student studying planetary science. "This process has been seen in meteorites many times but has only been seen on asteroids in one or two cases way out in the main asteroid belt, which is found between Mars and Jupiter."
Battle's adviser and study co-author Vishnu Reddy, a planetary sciences professor, discovered shock darkening on main belt asteroids in 2013 and 2014. Reddy co-leads the Space Domain Awareness lab at the Lunar and Planetary Laboratory with engineering professor Roberto Furfaro. Battle has worked in the lab since 2019.
"Impacts are very common in asteroids and any solid body in the solar system because we see impact craters on these objects from spacecraft images. But impact melt and shock-darkening effects on meteorites derived from these bodies are rare. Finding a near-Earth asteroid dominated by this process has implications for impact hazard assessment," Reddy said. "Adam's work has shown that ordinary chondrite asteroids can appear as carbonaceous in our classification tools if they are affected by shock darkening. These two materials have different physical strengths, which is important when trying to deflect a hazardous asteroid."
For this study, Battle, Reddy and their team used the RAPTORS system, a telescope atop the Kuiper Space Sciences building on campus, to collect data on 1998 OR2's surface composition and determined that it looked like an ordinary chondrite asteroid. Chondrite asteroids contain the minerals olivine and pyroxene and are lighter in appearance.
But when the team ran the data through a classification tool, it suggested the asteroid was instead a carbonaceous asteroid, a type of asteroid that is characteristically dark and relatively featureless.
"The mismatch was one of the early things that got the project going to investigate potential causes for the discrepancy," Battle said. "The asteroid is not a mixture of ordinary chondrite and carbonaceous asteroids, but rather it is definitely an ordinary chondrite, based on its minerology, which has been altered – likely through the shock darkening process – to look like a carbonaceous asteroid to the classification tool."
Shock darkening was hypothesized in the late 1980s but didn't gain traction and went unstudied until 2013 when the fireball over Russia produced meteorites with shock-darkened characteristics.
Scientists, including Reddy, started getting more interested in shock darkening, and Reddy soon discovered shock-darkened asteroids in the main asteroid belt. On Earth, 2%, or roughly 1,400 of about 60,000 ordinary chondrite meteorites have undergone some degree of shock or impact process, Battle said.
Researchers were able to rule out a lot of other potential reasons 1998 OR2 appeared to be a carbonaceous asteroid rather than an ordinary chondrite. One possible cause for the discrepancy could be space weathering, in which exposure to the space environment causes changes to the asteroid surface, but if that were the case, the asteroid would appear to be slightly redder in color than it is. Shock darkening is a process that can suppress the appearance of olivine and pyroxene while also darkening the asteroid's surface to look like a carbonaceous asteroid.
