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Photo of orbits of the G objects at the center of our galaxy

Astronomers discover class of strange objects near our galaxy’s enormous black hole

Photo of orbits of the G objects at the center of our galaxy

Orbits of the G objects at the center of our galaxy, with the supermassive black hole indicated with a white cross. Stars, gas and dust are in the background. Photo: Anna Ciurlo, Tuan Do/UCLA Galactic Center Group

Astronomers from UCLA’s Galactic Center Orbits Initiative have discovered a new class of bizarre objects at the center of our galaxy, not far from the supermassive black hole called Sagittarius A*. They published their research in the Jan. 16 issue of the journal Nature.

“These objects look like gas and behave like stars,” said co-author Andrea Ghez, UCLA’s Lauren B. Leichtman and Arthur E. Levine Professor of Astrophysics and director of the UCLA Galactic Center Group.

The new objects look compact most of the time and stretch out when their orbits bring them closest to the black hole. Their orbits range from about 100 to 1,000 years, said lead author Anna Ciurlo, a UCLA postdoctoral researcher.

Ghez’s research group identified an unusual object at the center of our galaxy in 2005, which was later named G1. In 2012, astronomers in Germany made a puzzling discovery of a bizarre object named G2 in the center of the Milky Way that made a close approach to the supermassive black hole in 2014. Ghez and her research team believe that G2 is most likely two stars that had been orbiting the black hole in tandem and merged into an extremely large star, cloaked in unusually thick gas and dust.

“At the time of closest approach, G2 had a really strange signature,” Ghez said. “We had seen it before, but it didn’t look too peculiar until it got close to the black hole and became elongated, and much of its gas was torn apart. It went from being a pretty innocuous object when it was far from the black hole to one that was really stretched out and distorted at its closest approach and lost its outer shell, and now it’s getting more compact again.”

“One of the things that has gotten everyone excited about the G objects is that the stuff that gets pulled off of them by tidal forces as they sweep by the central black hole must inevitably fall into the black hole,” said co-author Mark Morris, UCLA professor of physics and astronomy. “When that happens, it might be able to produce an impressive fireworks show since the material eaten by the black hole will heat up and emit copious radiation before it disappears across the event horizon.”

But are G2 and G1 outliers, or are they part of a larger class of objects? In answer to that question, Ghez’s research group reports the existence of four more objects they are calling G3, G4, G5 and G6. The researchers have determined each of their orbits. While G1 and G2 have similar orbits, the four new objects have very different orbits.

Ghez believes all six objects were binary stars — a system of two stars orbiting each other — that merged because of the strong gravitational force of the supermassive black hole. The merging of two stars takes more than 1 million years to complete, Ghez said.

“Mergers of stars may be happening in the universe more often than we thought, and likely are quite common,” Ghez said. “Black holes may be driving binary stars to merge. It’s possible that many of the stars we’ve been watching and not understanding may be the end product of mergers that are calm now. We are learning how galaxies and black holes evolve. The way binary stars interact with each other and with the black hole is very different from how single stars interact with other single stars and with the black hole.”

Ciurlo noted that while the gas from G2’s outer shell got stretched dramatically, its dust inside the gas did not get stretched much. “Something must have kept it compact and enabled it to survive its encounter with the black hole,” Ciurlo said. “This is evidence for a stellar object inside G2.”

“The unique dataset that Professor Ghez’s group has gathered during more than 20 years is what allowed us to make this discovery,” Ciurlo said. “We now have a population of ‘G’ objects, so it is not a matter of explaining a ‘one-time event’ like G2.”

The researchers made observations from the W.M. Keck Observatory in Hawaii and used a powerful technology that Ghez helped pioneer, called adaptive optics, which corrects the distorting effects of the Earth’s atmosphere in real time. They conducted a new analysis of 13 years of their UCLA Galactic Center Orbits Initiative data.

In September 2019, Ghez’s team reported that the black hole is getting hungrier and it is unclear why. The stretching of G2 in 2014 appeared to pull off gas that may recently have been swallowed by the black hole, said co-author Tuan Do, a UCLA research scientist and deputy director of the Galactic Center Group. The mergers of stars could feed the black hole.

The team has already identified a few other candidates that may be part of this new class of objects, and are continuing to analyze them.

Ghez noted the center of the Milky Way galaxy is an extreme environment, unlike our less hectic corner of the universe.

“The Earth is in the suburbs compared to the center of the galaxy, which is some 26,000 light-years away,” Ghez said. “The center of our galaxy has a density of stars 1 billion times higher than our part of the galaxy. The gravitational pull is so much stronger. The magnetic fields are more extreme. The center of the galaxy is where extreme astrophysics occurs — the X-sports of astrophysics.”

Ghez said this research will help to teach us what is happening in the majority of galaxies.

Other co-authors include Randall Campbell, an astronomer with the W.M. Keck Observatory in Hawaii; Aurelien Hees, a former UCLA postdoctoral scholar, now a researcher at the Paris Observatory in France; and Smadar Naoz, a UCLA assistant professor of physics and astronomy.

The research is funded by the National Science Foundation, W.M. Keck Foundation and Keck Visiting Scholars Program, the Gordon and Betty Moore Foundation, the Heising-Simons Foundation, Lauren Leichtman and Arthur Levine, Jim and Lori Keir, and Howard and Astrid Preston.

In July 2019, Ghez’s research team reported on the most comprehensive test of Einstein’s iconic general theory of relativity near the black hole. They concluded that Einstein’s theory passed the test and is correct, at least for now.

► Watch a four-minute film about Ghez’s research

►View an animation below of the orbits of the G objects, together with the orbits of stars near the supermassive black hole. Credit: Advanced Visualization Lab, National Center for Supercomputing Applications, University of Illinois

This article originally appeared in the UCLA Newsroom.

Unearthing Easter Island’s Moai

Two Moai are shown during excavations by Jo Anne Van Tilburg and her team at Rano Raraku quarry on Rapa Nui, better known as Easter Island. Photo credit: Easter Island Statue Project

Rapa Nui (or Easter Island, as it is commonly known) is home to the enigmatic Moai, stone monoliths that have stood watch over the island landscape for hundreds of years. Their existence is a marvel of human ingenuity — and their meaning a source of some mystery.

Ancient Rapanui carvers worked at the behest of the elite ruling class to carve nearly 1,000 Moai because they, and the community at large, believed the statues capable of producing agricultural fertility and thereby critical food supplies, according to a new study from Jo Anne Van Tilburg, director of the Easter Island Statue Project, recently published in Journal of Archaeological Science.

Van Tilburg and her team, working with geoarchaeologist and soils specialist Sarah Sherwood, believe they have found scientific evidence of that long-hypothesized meaning thanks to careful study of two particular Moai excavated over five years in the Rano Raraku quarry on the eastern side of the Polynesian island.

Van Tilburg’s most recent analysis focused on two of the monoliths that stand within the inner region of the Rano Raraku quarry, which is the origin of 95 percent of the island’s more than 1,000 Moai. Extensive laboratory testing of soil samples from the same area shows evidence of foods such as banana, taro and sweet potato.

Van Tilburg said the analysis showed that in addition to serving as a quarry and a place for carving statues, Rano Raraku also was the site of a productive agricultural area.

“Our excavation broadens our perspective of the Moai and encourages us to realize that nothing, no matter how obvious, is ever exactly as it seems. I think our new analysis humanizes the production process of the Moai,” Van Tilburg said.

Van Tilburg has been working on Rapa Nui for more than three decades. Her Easter Island Statue Project is supported in part by UCLA’s Cotsen Institute of Archaeology. Tom Wake, a Cotsen Institute colleague, analyzes small-animal remains from the excavation site. Van Tilburg also serves as director of UCLA’s Rock Art Archive.

Van Tilburg, in partnership with members of the local community, heads the first legally permitted excavations of Moai in Rano Raraku since 1955. Cristián Arévalo Pakarati, a noted Rapanui artist, is project co-director.

The soils in Rano Raraku are probably the richest on the island, certainly over the long term, Sherwood said. Coupled with a fresh-water source in the quarry, it appears the practice of quarrying itself helped boost soil fertility and food production in the immediate surroundings, she said. The soils in the quarry are rich in clay created by the weathering of lapilli tuff (the local bedrock) as the workers quarried into deeper rock and sculpted the Moai.

A professor of earth and environmental systems at the University of the South in Sewanee, Tenn., Sherwood joined the Easter Island Project after meeting another member of Van Tilburg’s team at a geology conference.

She wasn’t originally looking for soil fertility, but out of curiosity and research habit, she did some fine-scale testing of samples brought back from the quarry.

“When we got the chemistry results back, I did a double take,” Sherwood said. “There were really high levels of things that I never would have thought would be there, such as calcium and phosphorous. The soil chemistry showed high levels of elements that are key to plant growth and essential for high yields. Everywhere else on the island the soil was being quickly worn out, eroding, being leeched of elements that feed plants, but in the quarry, with its constant new influx of small fragments of the bedrock generated by the quarrying process, there is a perfect feedback system of water, natural fertilizer and nutrients.”

She said it also looks like the ancient indigenous people of Rapanui were very intuitive about what to grow — planting multiple crops in the same area, which can help maintain soil fertility.

The Moai that Van Tilburg’s team excavated were discovered upright in place, one on a pedestal and the other in a deep hole, indicating they were meant to remain there.

“This study radically alters the idea that all standing statues in Rano Raraku were simply awaiting transport out of the quarry,” Van Tilburg said. “That is, these and probably other upright Moai in Rano Raraku were retained in place to ensure the sacred nature of the quarry itself. The Moai were central to the idea of fertility, and in Rapanui belief their presence here stimulated agricultural food production.”

Van Tilburg and her team estimate the statues from the inner quarry were raised by or before A.D. 1510 to A.D.1645. Activity in this part of the quarry most likely began in A.D.1455. Most production of Moai had ceased in the early 1700s due to western contact.

The two statues Van Tilburg’s team excavated had been almost completely buried by soils and rubble.

“We chose the statues for excavation based on careful scrutiny of historical photographs and mapped the entire Rano Raraku inner region before initiating excavations,” she said.

Van Tilburg has worked hard to establish connections with the local community on Rapa Nui. The project’s field and lab teams are made up of local workers, mentored by professional archeologists and geologists.

The result of their collective efforts is a massive detailed archive and comparative database that documents more than 1,000 sculptural objects on Rapa Nui, including the Moai, as well as similar records on more than 200 objects scattered in museums throughout the world. In 1995, UNESCO named Easter Island a World Heritage Site, with most of the island’s sacred sites protected within Rapa Nui National Park.

This is the first definitive study to reveal the quarry as a complex landscape and to make a definitive statement that links soil fertility, agriculture, quarrying and the sacred nature of the Moai.

Van Tilburg and her team are working on another study that analyzes the rock art carvings that exist on only three of the Moai.

This article originally appeared in the UCLA Newsroom.

That Supermassive Black Hole in our Galaxy? It has a Friend.

Two black holes are entwined in a gravitational tango in this artist’s conception. Photo Credit: NASA/JPL-Caltech/SwRI/MSSS/Christopher Go

Smadar Naoz is an associate professor of physics and astronomy in the UCLA College. She wrote this article for The Conversation.

Do supermassive black holes have friends? The nature of galaxy formation suggests that the answer is yes, and in fact, pairs of supermassive black holes should be common in the universe.

I am an astrophysicist and am interested in a wide range of theoretical problems in astrophysics, from the formation of the very first galaxies to the gravitational interactions of black holes, stars and even planets. Black holes are intriguing systems, and supermassive black holes and the dense stellar environments that surround them represent one of the most extreme places in our universe.

The supermassive black hole that lurks at the center of our galaxy, called Sgr A*, has a mass of about 4 million times that of our sun. A black hole is a place in space where gravity is so strong that neither particles or light can escape from it. Surrounding Sgr A* is a dense cluster of stars. Precise measurements of the orbits of these stars allowed astronomers to confirm the existence of this supermassive black hole and to measure its mass. For more than 20 years, scientists have been monitoring the orbits of these stars around the supermassive black hole. Based on what we’ve seen, my colleagues and I show that if there is a friend there, it might be a second black hole nearby that is at least 100,000 times the mass of the sun.

Supermassive black holes and their friends

Almost every galaxy, including our Milky Way, has a supermassive black hole at its heart, with masses of millions to billions of times the mass of the sun. Astronomers are still studying why the heart of galaxies often hosts a supermassive black hole. One popular idea connects to the possibility that supermassive holes have friends.

To understand this idea, we need to go back to when the universe was about 100 million years old, to the era of the very first galaxies. They were much smaller than today’s galaxies, about 10,000 or more times less massive than the Milky Way. Within these early galaxies the very first stars that died created black holes, of about tens to thousand the mass of the sun. These black holes sank to the center of gravity, the heart of their host galaxy. Since galaxies evolve by merging and colliding with one another, collisions between galaxies will result in supermassive black hole pairs – the key part of this story. The black holes then collide and grow in size as well. A black hole that is more than a million times the mass of our sun is considered supermassive.

If indeed the supermassive black hole has a friend revolving around it in close orbit, the center of the galaxy is locked in a complex dance. The partners’ gravitational tugs will also exert its own pull on the nearby stars disturbing their orbits. The two supermassive black holes are orbiting each other, and at the same time, each is exerting its own pull on the stars around it.

The gravitational forces from the black holes pull on these stars and make them change their orbit; in other words, after one revolution around the supermassive black hole pair, a star will not go exactly back to the point at which it began.

Using our understanding of the gravitational interaction between the possible supermassive black hole pair and the surrounding stars, astronomers can predict what will happen to stars. Astrophysicists like my colleagues and me can compare our predictions to observations, and then can determine the possible orbits of stars and figure out whether the supermassive black hole has a companion that is exerting gravitational influence.

Using a well-studied star, called S0-2, which orbits the supermassive black hole that lies at the center of the galaxy every 16 years, we can already rule out the idea that there is a second supermassive black hole with mass above 100,000 times the mass of the sun and farther than about 200 times the distance between the sun and the Earth. If there was such a companion, then I and my colleagues would have detected its effects on the orbit of SO-2.

But that doesn’t mean that a smaller companion black hole cannot still hide there. Such an object may not alter the orbit of SO-2 in a way we can easily measure.

The physics of supermassive black holes

Supermassive black holes have gotten a lot of attention lately. In particular, the recent image of such a giant at the center of the galaxy M87 opened a new window to understanding the physics behind black holes.

The proximity of the Milky Way’s galactic center – a mere 24,000 light-years away – provides a unique laboratory for addressing issues in the fundamental physics of supermassive black holes. For example, astrophysicists like myself would like to understand their impact on the central regions of galaxies and their role in galaxy formation and evolution. The detection of a pair of supermassive black holes in the galactic center would indicate that the Milky Way merged with another, possibly small, galaxy at some time in the past.

That’s not all that monitoring the surrounding stars can tell us. Measurements of the star S0-2 allowed scientists to carry out a unique test of Einstein’s general theory of relativity. In May 2018, S0-2 zoomed past the supermassive black hole at a distance of only about 130 times the Earth’s distance from the sun. According to Einstein’s theory, the wavelength of light emitted by the star should stretch as it climbs from the deep gravitational well of the supermassive black hole.

The stretching wavelength that Einstein predicted – which makes the star appear redder – was detected and proves that the theory of general relativity accurately describes the physics in this extreme gravitational zone. I am eagerly awaiting the second closest approach of S0-2, which will occur in about 16 years, because astrophysicists like myself will be able to test more of Einstein’s predictions about general relativity, including the change of the orientation of the stars’ elongated orbit. But if the supermassive black hole has a partner, this could alter the expected result.

Finally, if there are two massive black holes orbiting each other at the galactic center, as my team suggests is possible, they will emit gravitational waves. Since 2015, the LIGO-Virgo observatories have been detecting gravitational wave radiation from merging stellar-mass black holes and neutron stars. These groundbreaking detections have opened a new way for scientists to sense the universe.

Any waves emitted by our hypothetical black hole pair will be at low frequencies, too low for the LIGO-Virgo detectors to sense. But a planned space-based detector known as LISA may be able to detect these waves which will help astrophysicists figure out whether our galactic center black hole is alone or has a partner.

This article originally appeared in the UCLA Newsroom.

Photograph of homeless tent encampment.

L.A. could better target homeless prevention services with predictive analytics

Photograph of homeless tent encampment.

Photo credit: California Policy Lab

Each year, 2 million single adults receive housing, health, and emergency services from Los Angeles County. About 2% of them — around 76,000 people — will become homeless. Predictive modeling could help address the homelessness crisis in Los Angeles County, according to a report by researchers from the California Policy Lab at UCLA, and the Poverty Lab at the University of Chicago Harris School of Public Policy.

Using data from seven Los Angeles County agencies about services they provided to county residents between 2012 and 2016 — the residents’ names and personally identifiable information were omitted and each person was assigned an ID number for the study — researchers developed a model to predict which 3,000 residents were most likely to become homeless in 2017.

The researchers then checked the accuracy of their predictions against county records, and found that 46% of the people predicted by the model to be at risk for first-time homelessness or a repeat spell of homelessness did in fact become homeless at some point during 2017.

“Bringing together data from multiple county agencies gave us a more nuanced understanding about what’s happening to people right before they slip into homeless and how services can be better targeted to prevent that from happening,” said Till von Wachter, a UCLA economics professor and co-author of the report.  Von Wachter is also faculty director at the California Policy Lab.

The California Policy Lab pairs UCLA and other UC researchers with policymakers to solve urgent social problems, including homelessness, poverty, crime and education inequality.

The research informed an action plan that was developed by the county-led Mainstream Systems Homelessness Prevention Workgroup. That plan, which was submitted to the Los Angeles County Board of Supervisors on Dec. 16, recommends that the county use predictive models to intervene with adults who are identified as having a high risk for homelessness before they reach a crisis.

It also suggests that the county launch a multidisciplinary homelessness prevention unit that includes representatives of the county’s departments of mental health, health services and social services, and the sheriff and probation offices. The unit would accept referrals from the risks lists generated by the predictive models, identify which programs or services would be most helpful for each individual, and then reach out to people to connect them to those services.

The plan is expected to receive $3 million in funding during 2020 from Measure H, a sales tax approved by Los Angeles County voters in 2017 to help address the homeless crisis, in addition to drawing some existing resources from Los Angeles County departments.

“Last year, despite providing housing to tens of thousands of people, we saw more and more individuals and families becoming homeless,” said Phil Ansell, the director of the Los Angeles County Homeless Initiative. “The county is focused on using strategic approaches to preventing homelessness, and these groundbreaking models will make it possible to reach those who need us the most before they reach the crisis point and fall into homelessness.”

The models allowed researches to identify warning signs that could help local governments intervene early, especially for residents living in deep poverty, said Harold Pollack, the Helen Ross Professor at the University of Chicago School of Social Service Administration and a co-author of the study. The research that led to the new recommendations was begun at Chicago.

“The models suggest that sharp spikes in service use, increasingly frequent service use and the receipt of multiple services from a single agency are all warning signs that someone is at high risk for homelessness,” Pollack said. “We’re now diving deeper into the models with our Los Angeles County partners to learn more and to see how these results can help focus public health and social services to this vulnerable population.”

Janey Rountree, executive director of the California Policy Lab at UCLA, said using the predictive models could go a long way toward making sure homeless prevention services reach the right people at the right time.

“Predictive modeling can help ensure that happens, before they’re in a full-blown crisis,” she said. “We look forward to seeing its impact in connecting people to the help they need.”

The study also found:

  • Effectively serving the 1% of county clients who have the greatest risk for a new homeless spell would prevent nearly 6,900 homeless spells in one year.
  • County residents who have the highest risk for homelessness are interacting with multiple agencies.
  • Falling into homelessness happens very quickly, typically within six months of a precipitating event, meaning that Los Angeles County and service providers must react quickly.

The research was provided at no cost to the county. Financial support was provided by Arnold Ventures and the Max Factor Family Foundation.

This article originally appeared in the UCLA Newsroom.

Chronic opioid treatment may raise risk of post-traumatic stress disorder, study finds

Senior author Michael Fanselow said the research suggests that chronic opioid use increases susceptibility to developing anxiety disorders. Photo credit: Reed Hutchinson/UCLA

While opioids are often prescribed to treat people with trauma-related pain, a new UCLA-led study suggests doctors should use caution before prescribing the drug to those they believe may experience severe stress in the future, in order to reduce the risk the patient will develop PTSD.

In the study, researchers administered doses of the opioid morphine to a group of 22 mice for one week, then gave the mice relatively strong foot shocks. After the morphine wore off, the mice were given mild electric foot shocks. These mice showed a substantially longer “freezing response” than a second, control group of 24 mice that had not been given morphine. When mice recall a frightening memory, they freeze. Their heart rates and blood pressure go up, and the more frightening the memory, the more they freeze.

“While we are generally aware that drug use, such as that in the current opioid crisis, has many deleterious effects, our results suggest yet another effect — increased susceptibility to developing anxiety disorders,” said senior author Michael Fanselow, UCLA distinguished Staglin family professor of psychology and director of UCLA’s Staglin Family Music Festival Center for Brain and Behavioral Health. “As opioids are often prescribed to treat symptoms such as pain that may accompany trauma, caution may be needed because this may lead to a greater risk of developing PTSD, if exposed to further traumatic events, such as an accident, later on.”

“The foot shocks produced lasting fear and anxiety-like behaviors, such as freezing,” Fanselow said.

“Our data are the first to show a possible effect of opioids on future fear learning, suggesting that a person with a history of opioid use may become more susceptible to the negative effects of stress,” Fanselow said. “The ability of opioids to increase PTSD-like symptoms far outlasted the direct effects of the drug or withdrawal from the drug, suggesting the effect may continue even after opioid treatment has stopped.”

Fanselow’s view is if there is reason to believe a patient is likely to experience severe emotional stress after opioid treatment, then doctors should use caution about prescribing an opioid. If opioid use is medically called for, then the patient should be kept away from potentially stressful situations. So, for example, a soldier treated with opioids for pain should not be sent back into combat for a period of time, he said. The development of post-traumatic stress disorder requires some stressful experience after opioid use, he said.

The researchers also gave some of the mice morphine after the initial trauma had occurred but before exposing them to the second, mild stressor. They found that mice treated with morphine after the initial trauma did not show enhanced fear learning following exposure to the mild stressor. This finding suggests that chronic use of opioids before — but not after — a traumatic event occurs affects fear learning during subsequent stressful events.

The researchers concluded the mice given morphine were more susceptible to post-traumatic stress disorder than the control group of mice not given any opioids, and inferred that people with a history of using opioids are more susceptible to PTSD than the general population.

The study is published in Neuropsychopharmacology, an international scientific journal focusing on clinical and basic science research that advances understanding of the brain and behavior.

The research was funded by the National Institute on Drug Abuse and National Institute of Mental Health.

An opiate is a drug naturally derived from the opium poppy plant, such as heroin, morphine and codeine. Opioid is a broader term that includes opiates and any substance, natural or synthetic, that binds to the brain’s opioid receptors — which play a key role in controlling pain, rewards and addictive behaviors. Synthetic opioids include the prescription painkillers Vicodin and OxyContin, as well as fentanyl and methadone.

Substance abuse and PTSD often go hand-in-hand, Fanselow said, and people with PTSD often take drugs to self-medicate. Nearly 40% of people with PTSD also have a drug disorder.

Fanselow and colleagues reported last month that a traumatic brain injury causes changes in a brain region called the amygdala; and the brain processes fear differently after such an injury.

This article originally appeared in the UCLA Newsroom.

Image of interstellar comet.

New NASA image provides more details about first observed interstellar comet

Image of interstellar comet.

The interstellar comet Comet 2I/Borisov (blueish image at right) near a spiral galaxy (left), in an image taken Nov. 16. Photo credit: NASA, ESA and David Jewitt/UCLA

A new image from NASA’s Hubble Space Telescope provides important new details about the first interstellar comet astronomers have seen in our solar system.

The comet, called Comet 2I/Borisov (the “I” stands for interstellar), was spotted near a spiral galaxy known as 2MASX J10500165-0152029. It was approximately 203 million miles from Earth when the image was taken on Nov. 16.

“Data from the Hubble Space Telescope give us the best measure of the size of comet 2I/Borisov’s nucleus, which is the really important part of the comet,” said David Jewitt, a UCLA professor of planetary science and astronomy who analyzed and interpreted the data from the new image.

Jewitt collaborated on the new analysis with colleagues from the University of Hawaii, Germany’s Max Planck Institute for Solar System Research, the Space Telescope Science Institute in Baltimore and Johns Hopkins University’s Applied Physics Laboratory. The scientists were surprised to learn that the nucleus has a radius measuring only about half of a kilometer — or less than one-fifteenth the size that earlier investigations suggested it might be.

“That is important because knowing its size helps us to determine the total number, and mass, of other similar objects in the solar system and the Milky Way,” Jewitt said. “2I/Borisov is the first known interstellar comet, and we would like to learn how many others there are.”

The comet is traveling at a breathtaking speed of 110,000 miles per hour — one of the fastest comets ever seen, Jewitt said. More commonly, comets travel at about half that speed.

Crimean astronomer Gennady Borisov discovered the comet on Aug. 30, using a telescope he built. Based on precise measurements of its changing position, the International Astronomical Union’s Minor Planet Center calculated a likely orbit for the comet, which shows that it came from elsewhere in the galaxy. Jewitt said its precise point of origin is unknown.

A second Hubble Space Telescope image of the comet, taken on Dec. 9, shows the comet even closer to Earth, approximately 185 million miles from Earth, he said.

Comets are icy bodies thought to be fragments left behind when planets form in the outer parts of planetary systems.

Observations by numerous telescopes show that the comet’s chemical composition is similar to that of comets previously observed in our solar system, which provides evidence that comets also form around other stars, Jewitt said. By mid-2020, the comet will have zoomed past Jupiter on its way back into interstellar space, where it will drift for billions of years, Jewitt said.

This article originally appeared in the UCLA Newsroom.

Photo of student smiling.

Meet UCLA Student Researcher Julia Nakamura

Photo of student smiling.

Fourth-year UCLA student researcher Julia Nakamura

Meet fourth-year UCLA student researcher Julia Nakamura!

Julia majors in Psychobiology with a minor in Gerontology and is in our Undergraduate Research Scholars Program. The title of her research project is “The Role of Social Support in the Association between Early Life Stress, Depression, and Inflammation in Older Adults.”

 

How did you first get interested in your research project?

UCLA’s Cluster course “Frontiers in Human Aging” initially sparked my interest in aging populations. Through a service learning project at ONEgeneration Adult Day Care Center, I directly witnessed the burden of chronic disease in later-life adults and realized the pressing need to understand the mechanisms underlying these adverse health outcomes. Through my coursework in psychology, I became interested in the psychological factors that influence biological mechanisms and have the potential to positively impact the trajectory of chronic disease outcomes.

I began research in psychology in Dr. Julienne Bower’s Mind-Body Lab under the direction of Dr. Kate Kuhlman. We study the effects of childhood adversity on biological and behavioral responses to psychological stress. My experiences in this lab led me to wonder what factors could mitigate adverse physical and mental health outcomes from stressful experiences, specifically in older adults. My honors research project examines if social support moderates the relationship between early-life stress, depressive symptoms, and inflammation in older adults using data from the Health and Retirement Study.

What has been the most exciting aspect of your research so far?

Getting to test my own research questions has been the best part of this project. Specifically, it has been really exciting for me to run my own data analyses for the first time with Dr. Kuhlman’s guidance. Experiencing the “behind-the-scenes” of research and systematically moving through the steps of conducting an independent project has been really informative. This project has helped me to feel that I am truly developing the skill set of an independent researcher, which is very exciting!

What has surprised you about your research or the research process?

The immensely collaborative nature of research in academia was quite surprising to me when I first started on this project. Through my research, I’ve had the privilege of working with several scientists and professors who are experts in their respective areas of study. They have all welcomed me and helped to make my project as scientifically sound and comprehensive as possible. Research really builds on itself. Learning from other people’s projects and ideas, even if they are outside of your immediate area of study, can result in high levels of collaboration and really interesting research!

What is one piece of advice you have for other UCLA students thinking about doing research?

I would advise students interested in research to actively pursue research opportunities. There are plenty of amazing opportunities to be involved in research at UCLA, but you have to seek them out. It can be intimidating to take the initial steps to reach out to professors and discuss their research interests, but it is so worthwhile to find a lab and professor that are a good fit! I would recommend that students find an area of study that they are really passionate about. I think that your passion for your area of study and your continued curiosity will drive your research questions and help you get the most out of each research experience.

What effect do you hope your research has in your field, at UCLA, in your community, or in the world?

I hope to spend my life contributing to our understanding of the biobehavioral processes that promote mental and physical health across the lifespan. As the number of older adults (a majority of whom have at least one chronic disease) increase in our society, it is now more important than ever to identify potential intervention targets that can improve the trajectory of chronic disease outcomes.

This article originally appeared on the Undergraduate Research Center website.

Picture of a valley oak tree.

One of California’s iconic tree species offers lessons for conservation

Picture of a valley oak tree.

The valley oak, the largest oak in California, grows to over 100 feet tall and provides habitat and food for a variety of animals. Photo credit: Victoria Sork/UCLA

 

With increasing regularity, Californians are witnessing firsthand the destructive power of wildfires. But not everyone sees what happens after the flames die down, when debris is cleared, homes and lives rebuilt — and trees replanted to help nature recover.

New research led by UCLA evolutionary biologist Victoria Sork examines whether the trees being replanted in the wake of California’s fires will be able to survive a climate that is continuing to warm.

The study, which is published in the Proceedings of the Natural Academy of Sciences, focuses on California’s iconic valley oak. The research is among the first to demonstrate the potential of using genomics to inform conservation strategies — essentially giving species an evolutionary boost. The study showed that planting trees that are genetically better suited to higher temperatures makes them more likely to survive and grow to maturity.

“When we think about managing ecosystems under rapidly changing climates, we have to realize trees need to be able to survive past 50 years,” Sork said.

The paper also discovered something surprising: The valley oak, an essential component of many ecosystems in California, is already poorly adapted to its environment — even considering climate conditions in 2019.

“They actually seem to grow better in cooler climates than they’re in right now,” said Luke Browne, a postdoctoral scholar at the UCLA La Kretz Center for California Conservation Science and the study’s lead author. “They might grow better if climates were more like they were 21,000 years ago, during the last ice age.”

During the peak of the last ice age, summer temperatures were about 4 to 5 degrees Celsius colder, and ice covered most of Canada and mountainous areas of the U.S.

In the fields of conservation and land management, it is a common assumption that plants and animals are adapted to their environments — that’s how evolution and natural selection are supposed to work. The new research casts doubt on that assumption.

The study is part of an ongoing project initiated by Sork and Jessica Wright, an expert in conservation genetics at the USDA Forest Service, more than 10 years ago.

Researchers gathered 11,000 seeds from 94 locations throughout the trees’ range, which stretches from the Santa Monica Mountains to the Cascade foothills in the northern part of the state. They grew them to saplings in a greenhouse and planted them in two large experimental gardens, in Chico and Placerville, California. They tracked how well trees from different locations grew, and sequenced the genomes of their mother trees to link genetic information and growth rates.

The researchers then identified which genetic variants would be more likely to thrive as climate change continues to warm California. They predicted that, under predicted future warmer temperatures, trees containing beneficial genetic variations would have 11% higher growth rates than the average for all of the trees in the experiment, and 25% higher growth rates than the trees without the beneficial variations.

Information like that could help the U.S. Forest Service, for example, in its efforts to restore forests with species that have the best chance for long-term survival.

“Studies like this one provide valuable insights that help land managers make informed decisions on reforestation projects,” Wright said. “When planting trees in a particular location, managers have to decide where to collect the acorns.”

By 2070, average temperatures in the state are projected to be up to 4.8 degrees warmer than they were during the mid- to late 20th century.

“That’s going to have consequences for how fast these trees grow,” Browne said. “We’re at a challenging time to figure out the best way to do conservation science. This paper shows one approach we could use that takes advantage of modern genomics.”

The study did not determine why valley oaks are not well adapted to their environment. It might be because the climate has already warmed up so much, the trees’ long lifespans — up to 500 years — or some other, unknown factor.

The valley oak is the largest oak in California; it grows to over 100 feet tall, and has dark green leaves and a deeply grooved trunk. It is considered a foundational species because it provides habitat and food for a variety of animals, including squirrels, birds, deer and insects. In parts of the state, it is one of the only species of tree that exists. Valley oaks provide benefits to humans, too: filtering water and providing shady places to escape the heat.

Although it focuses on the oak, the paper has broader implications for conservation science in a changing climate — especially for species that evolve and adapt slowly. That’s what Sork and Wright were thinking when they initiated the project.

At the time, they hoped to find conservation strategies that could eventually be implemented using genetic information alone — without extensive field experiments.

“Not everyone in the world is going to be able to collect 11,000 seeds and plant them in a common garden,” Sork said.

This article originally appeared in the UCLA Newsroom.

Black hole at the center of our galaxy appears to be getting hungrier

Rendering of a star called S0-2 orbiting the supermassive black hole at the center of the Milky Way. It did not fall in, but its close approach could be one reason for the black hole’s growing appetite. Photo credit: Nicolle Fuller/National Science Foundation

The enormous black hole at the center of our galaxy is having an unusually large meal of interstellar gas and dust, and researchers don’t yet understand why.

“We have never seen anything like this in the 24 years we have studied the supermassive black hole,” said Andrea Ghez, UCLA professor of physics and astronomy and a co-senior author of the research. “It’s usually a pretty quiet, wimpy black hole on a diet. We don’t know what is driving this big feast.”

paper about the study, led by the UCLA Galactic Center Group, which Ghez heads, is published today in Astrophysical Journal Letters.

The researchers analyzed more than 13,000 observations of the black hole from 133 nights since 2003. The images were gathered by the W.M. Keck Observatory in Hawaii and the European Southern Observatory’s Very Large Telescope in Chile. The team found that on May 13, the area just outside the black hole’s “point of no return” (so called because once matter enters, it can never escape) was twice as bright as the next-brightest observation.

They also observed large changes on two other nights this year; all three of those changes were “unprecedented,” Ghez said.

The brightness the scientists observed is caused by radiation from gas and dust falling into the black hole; the findings prompted them to ask whether this was an extraordinary singular event or a precursor to significantly increased activity.

“The big question is whether the black hole is entering a new phase — for example if the spigot has been turned up and the rate of gas falling down the black hole ‘drain’ has increased for an extended period — or whether we have just seen the fireworks from a few unusual blobs of gas falling in,” said Mark Morris, UCLA professor of physics and astronomy and the paper’s co-senior author.

The team has continued to observe the area and will try to settle that question based on what they see from new images.

“We want to know how black holes grow and affect the evolution of galaxies and the universe,” said Ghez, UCLA’s Lauren B. Leichtman and Arthur E. Levine Professor of Astrophysics. “We want to know why the supermassive hole gets brighter and how it gets brighter.”

► UCLA astronomers discussed the project in a Keck Observatory video

The new findings are based on observations of the black hole — which is called Sagittarius A*, or Sgr A* — during four nights in April and May at the Keck Observatory. The brightness surrounding the black hole always varies somewhat, but the scientists were stunned by the extreme variations in brightness during that timeframe, including their observations on May 13.

“The first image I saw that night, the black hole was so bright I initially mistook it for the star S0-2, because I had never seen Sagittarius A* that bright,” said UCLA research scientist Tuan Do, the study’s lead author. “But it quickly became clear the source had to be the black hole, which was really exciting.”

One hypothesis about the increased activity is that when a star called S0-2 made its closest approach to the black hole during the summer 2018, it launched a large quantity of gas that reached the black hole this year.

Another possibility involves a bizarre object known as G2, which is most likely a pair of binary stars, which made its closest approach to the black hole in 2014. It’s possible the black hole could have stripped off the outer layer of G2, Ghez said, which could help explain the increased brightness just outside the black hole.

Morris said another possibility is that the brightening corresponds to the demise of large asteroids that have been drawn in to the black hole.

No danger to Earth

The black hole is some 26,000 light-years away and poses no danger to our planet. Do said the radiation would have to be 10 billion times as bright as what the astronomers detected to affect life on Earth.

Astrophysical Journal Letters also published a second article by the researchers, describing speckle holography, the technique that enabled them to extract and use very faint information from 24 years of data they recorded from near the black hole.

Ghez’s research team reported July 25 in the journal Science the most comprehensive test of Einstein’s iconic general theory of relativity near the black hole. Their conclusion that Einstein’s theory passed the test and is correct, at least for now, was based on their study of S0-2 as it made a complete orbit around the black hole.

► Watch a four-minute film about Ghez’s research

Ghez’s team studies more than 3,000 stars that orbit the supermassive black hole. Since 2004, the scientists have used a powerful technology that Ghez helped pioneer, called adaptive optics, which corrects the distorting effects of the Earth’s atmosphere in real time. But speckle holography enabled the researchers to improve the data from the decade before adaptive optics came into play. Reanalyzing data from those years helped the team conclude that they had not seen that level of brightness near the black hole in 24 years.

“It was like doing LASIK surgery on our early images,” Ghez said. “We collected the data to answer one question and serendipitously unveiled other exciting scientific discoveries that we didn’t anticipate.”

Co-authors include Gunther Witzel, a former UCLA research scientist currently at Germany’s Max Planck Institute for Radio Astronomy; Mark Morris, UCLA professor of physics and astronomy; Eric Becklin, UCLA professor emeritus of physics and astronomy; Rainer Schoedel, a researcher at Spain’s Instituto de Astrofısica de Andalucıa; and UCLA graduate students Zhuo Chen and Abhimat Gautam.

The research is funded by the National Science Foundation, W.M. Keck Foundation, the Gordon and Betty Moore Foundation, the Heising-Simons Foundation, Lauren Leichtman and Arthur Levine, and Howard and Astrid Preston.

This article originally appeared in the UCLA Newsroom.

UCLA receives $20 million to establish UCLA Bedari Kindness Institute

Jennifer and Matthew C. Harris ‘84.

The Bedari Foundation, established by philanthropists Jennifer and Matthew C. Harris, has given $20 million to the UCLA College to establish the UCLA Bedari Kindness Institute.

The institute, which is housed in the division of social sciences, will support world-class research on kindness, create opportunities to translate that research into real-world practices, and serve as a global platform to educate and communicate its findings. Among its principal goals are to empower citizens and inspire leaders to build more humane societies.

“Universities should always be places where we teach students to reach across lines of difference and treat one another with empathy and respect — even when we deeply disagree,” UCLA Chancellor Gene Block said. “The UCLA Bedari Kindness Institute will bring the best thinking to this vital issue and, I think, will allow us to have a real social impact on future generations.”

The institute, which will begin operating immediately, will take an interdisciplinary approach to understanding kindness — through evolutionary, biological, psychological, economic, cultural and sociological perspectives. It will focus on research about the actions, thoughts, feelings and social institutions associated with kindness and will bring together researchers from across numerous disciplines at UCLA and at external organizations.

The inaugural director of the institute is Daniel Fessler, a UCLA anthropology professor whose research interests include exploring how witnessing acts of remarkable kindness can cause an uplifting emotional experience that in turn motivates the observer to be kind. Studies by Fessler and his colleagues have shed light on why some people are open to that type of “contagious kindness” experience.

The Bedari Foundation is a private family foundation whose aim is to enable significant cultural shifts in the fields of health and wellness, community displacement and environmental conservation.

“Our vision is that we will all live in a world where humanity discovers and practices the kindness that exists in all of us,” said Matthew Harris, the foundation’s co-founder and a 1984 UCLA graduate. “Much research is needed to understand why kindness can be so scarce in the modern world. As we seek at Bedari to bridge the divide between science and spirituality, through the establishment of the UCLA Bedari Kindness Institute we hope to educate and empower more and more people in the practice of kindness.”

Already, a range of researchers at UCLA are studying the types of questions that will be the basis of the institute’s work. For example, UCLA anthropologists are examining how kindness spreads from person to person and group to group. UCLA sociologists are analyzing how people who regularly act unkind might be encouraged to engage in kind acts instead, and UCLA psychologists are researching how kindness can improve people’s moods and reduce symptoms of depression. Others are pursuing research on changes in neurobiology and behaviors resulting from mindfulness, and how those changes can influence kindness and people’s mental, physical and social well-being.

“In the midst of current world politics, violence and strife, the UCLA Bedari Kindness Institute seeks to be an antidote,” said Darnell Hunt, dean of the UCLA division of social sciences. “Rooted in serious academic work, the institute will partner and share its research on kindness broadly in accessible formats. The Bedari Foundation’s extraordinary gift is truly visionary and we are grateful for its support and leadership.”

The Kindness Institute will provide seed funding for research projects that examine the social and physical mechanics of kindness and how kindness might be harnessed to create more humane societies. It also will provide mindfulness awareness training to students, faculty and staff and in underserved Los Angeles communities, and host an annual conference at which presenters will examine new discoveries in kindness research, among other activities.

“The mission of the Kindness Institute perfectly aligns with that of the division of social sciences, where engaging the amazing diversity and social challenges shaping Los Angeles routinely inspires research that has the potential to change the world,” Hunt said.

The gift is part of the Centennial Campaign for UCLA, which is scheduled to conclude in December.