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The galactic chimneys (yellow-orange areas extending vertically) are centered on the supermassive black hole at the center of our galaxy.

Giant X-ray ‘chimneys’ are exhaust vents for vast energies produced at Milky Way’s center

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The galactic chimneys (yellow-orange areas extending vertically) are centered on the supermassive black hole at the center of our galaxy.

The galactic chimneys (yellow-orange areas extending vertically) are centered on the supermassive black hole at the center of our galaxy.

 

The center of our galaxy is a frenzy of activity. A behemoth black hole — 4 million times as massive as the sun — blasts out energy as it chows down on interstellar detritus while neighboring stars burst to life and subsequently explode.

Now, an international team of astronomers has discovered two exhaust channels — dubbed “galactic center chimneys” — that appear to funnel matter and energy away from the cosmic fireworks in the Milky Way’s center, about 28,000 light-years from Earth.

Mark Morris, a UCLA professor of astronomy and astrophysics, contributed to the research, which will be published March 21 in the journal Nature.

“We hypothesize that these chimneys are exhaust vents for all the energy released at the center of the galaxy,” Morris said.

All galaxies are giant star-forming factories, but their productivity can vary widely — from one galaxy to the next and even over the course of each galaxy’s lifetime. One mechanism for throttling the rate of star production is the fountain of matter and energy whipped up by the heavyweight black hole that lurks at a galaxy’s center.

“Star formation determines the character of a galaxy,” Morris said. “And that’s something we care about because stars produce the heavy elements out of which planets — and life — are made.”

To better understand what becomes of that outflow of energy, Morris and his colleagues pointed the European Space Agency’s XMM-Newton satellite, which detects cosmic X-rays, toward the center of the Milky Way. Because X-rays are emitted by extremely hot gas, they are especially useful for mapping energetic environments in space.

In images they collected from 2016 to 2018 and in 2012, the researchers found two plumes of X-rays — the galactic center chimneys — stretching in opposite directions from the central hub of the galaxy. Each plume originates within about 160 light-years of the supermassive black hole and spans over 500 light-years.

The chimneys hook up to two gargantuan structures known as the Fermi bubbles, cavities carved out of the gas that envelops the galaxy. The bubbles, which are filled with high-speed particles, straddle the center of the galaxy and stretch for 25,000 light-years in either direction. Some astronomers suspect that the Fermi bubbles are relics of massive eruptions from the supermassive black hole, while others think the bubbles are blown out by hordes of newly born stars. Either way, the chimneys could be the conduits through which high-speed particles get there.

Understanding how energy makes its way from a galaxy’s center to its outer limits could provide insights into why some galaxies are bursting with star formation whereas others are dormant.

“In extreme cases, that fountain of energy can either trigger or shut off star formation in the galaxy,” Morris said.

Our galaxy isn’t quite that extreme — other galaxies have fountains powered by central black holes weighing a thousand times more than ours — but the Milky Way’s center provides an up-close look at what might be happening in galaxies that are more energetic.

“We know that outflows and winds of material and energy emanating from a galaxy are crucial in sculpting and altering that galaxy’s shape over time — they’re key players in how galaxies, and other structures, form and evolve throughout the cosmos,” said lead author Gabriele Ponti of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany. “Luckily, our galaxy gives us a nearby laboratory to explore this in detail, and probe how material flows out into the space around us.”

Morris said the centers of the nearest galaxies are hundreds to thousands of times farther away than our own. “The amount of energy coming out of the center of our galaxy is limited, but it’s a really good example of a galactic center that we can observe and try to understand,” he said.

Nine authors from five countries contributed to the study. The research was funded by NASA, the French National Center for Space Studies, the French National Agency for Research, the German Federal Ministry of Economics and Technology, the German Aerospace Center and the Max Planck Society.

Photo of Kara Cooney, professor of Egyptian art and architecture at UCLA.

The parallels of female power in ancient Egypt and modern times

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Photo of Kara Cooney, professor of Egyptian art and architecture at UCLA.

Kara Cooney, professor of Egyptian art and architecture at UCLA.

 

Over the course of 3,000 years of Egypt’s history, six women ascended to become female kings of the fertile land and sit atop its authoritarian power structure. Several ruled only briefly, and only as the last option in their respective failing family line. Nearly all of them achieved power under the auspices of attempting to protect the throne for the next male in line. Their tenures prevented civil wars among the widely interbred families of social elites. They inherited famines and economic disasters. With the exception of Cleopatra, most remain a mystery to the world at large, their names unpronounceable, their personal thoughts and inner lives unrecorded, their deeds and images often erased by the male kings that followed, especially if the women were successful.

In her latest National Geographic book, “When Women Ruled the World” Kara Cooney, professor of Egyptian art and architecture and chair of the UCLA Department of Near Eastern Languages and Cultures, tells the stories of these six women: Merneith (some time between 3000–2890 B.C.), Neferusobek (1777–1773 B.C.), Hatsepshut (1473–1458 B.C.), Nefertiti (1338–1336 B.C.), Tawroset (1188–1186 B.C.) and Cleopatra (51–30 B.C.).

As we ponder Women’s History Month, and look forward toward a U.S. presidential primary campaign that includes more women candidates than ever before, we asked Cooney about themes of female power and what Egypt can illuminate for us.

Your book illustrates that Egyptian society valued and embraced women’s rule when it was deemed necessary, but these are not instances of feminism. Their attempts to rule was really about keeping the set structure in place.

Studying Egypt is a study of power, and specifically of how to maintain the power of the one over the many. That story also always includes examples of how women are used as tools to make sure the authoritarian regime flourishes. This is the most interesting part to me because then the whole tragedy of the study, of the book, is that this is not about feminism at all. It’s not about feminists moving forward, it’s not about the feminist agenda. It’s not about anything but protecting the status quo, the rich staying rich, the patriarchy staying in charge and the system continuing. We still do this, us women. Women work for the patriarchy without thinking about it, all the time. In the end, did women rule the world? Yes, they did rule the world but did it change anything? No.

I want to look at our world the same way. It doesn’t matter if we have a female president. What matters is how people rule and whose agendas are served.

People who have been to Egypt probably know the name Hatshepsut and maybe Nefertiti, but clearly the most pervasive female cultural Egyptian reference is Cleopatra. Why is she the one? Do we just have more materials related to her?

No, it’s because when you are successful, you can very easily be erased. Cleopatra failed in her efforts to hold on to power and hold onto native rule in Egypt. When you are a failure, it’s aberrant, strange and it spins a good tale. It’s a great story, failure. Whereas success is doing what everyone did before you and what everyone will do after you. It’s the same and nobody cares. It’s the same as being a successful female in a meeting or a successful female who shares a great idea with her boss and her boss takes that idea into the meeting while she sits there meekly, letting the boss take it for his or her own because it’s a successful, great idea.

So it’s the women who are the greatest successes in the story who are the most successfully erased. The women who did it all wrong and didn’t leave their land better than when they found it, who are remembered as cautionary tales. That’s our cultural memory. That’s why everyone can pronounce the name Cleopatra and no one has any idea how to pronounce Hatshepsut. She is not in our cultural memory. It doesn’t serve our patriarchal system to add her to it.

But remember, in the Egyptian mindset Cleopatra wasn’t a failure. She fought Rome and lost, but in the Arabic sources Cleopatra is remembered as an adherent to Egyptian philosophy, a freedom fighter against Rome and as a learned patriot to her people.

Book cover of When Women Ruled the World

How does the framework of Egypt’s long and relatively well-documented history and culture inform our perspectives on power as American citizens, a country of such a comparatively short history and governance?

Egypt is such a gift. When I get asked — and I do — “Why bother devoting your life to this place that’s been gone for 2,000 years and studying people that are as old as 5,000 years?” the answer is that Egypt provides me with 3,000 years of the same cultural system, religious system, government system and language system. I can follow them through booms and busts, through collapse and resurgence and see human reactions to prosperity and pain. That’s really useful. We are in this infancy of 250 years and we think we are so smart, we think we are post-racial, post-sexist and all of these things. But we’re not. Egypt is a huge gift to compare the situation that you are in to the past to see how you might better face the future.

It must be difficult to unearth women’s stories because of the ways in which historical records from around the world largely excluded information about them.

That’s the frustration of working with Egypt. We can’t forget that this is an authoritarian regime. It’s not a competitive place where I can get a speech from a competitor and try to understand a different viewpoint and agenda. It’s my responsibility as a historian of this regime to try and break it down and see what the truth is between the lines. For these women in power it’s even harder because so many of them were erased when their stories did not fit the patriarchal narrative. My job is to be a historical reconstructionist without being a revisionist. I’m interested in seeing how people work within a system and why we are so opposed, even hostile, to female power.

Why are we so hostile to female power?

The stereotype is that the female is going to use emotionality, her own and others, to manipulate and lie, to shame and guilt people into doing something. The man somehow won’t do that. He will be a straight shooter.

There is the idea that there is the masculine emotionality and a female emotionality. This female emotionality, which many men also bear, is the reason we don’t allow them to wield power because they’re happy, sad, up, down. They feel too many emotions that cannot be allowed.

The men that we ask to lead must suppress those emotions and show this even-keeled strength or only anger and no other softer emotions and then only strategically. We demand a kind of emotionality from our leaders that I find quite stunted and I want to know what the evolutionary biology of that is because a lot of this is a knee-jerk reaction to what serves us better in a short-term, acute time of crisis. I think we all need to discuss what it is about that female emotionality, of connecting with our own emotions and others or even manipulating our emotions for our own gain, that is so problematic.

As of now, six women have announced Democratic presidential campaigns for 2020. What does our historical knowledge of what happens to women when they seek power bode for the coming election season?

I get rather cynical about it, to be honest. Already I see the dialogue revolving around deceit and not being a straight shooter.

Again, it’s that double standard that you wouldn’t necessarily get with a man. It’s interesting to see how people are judging women based on emotionality and how much of that they show, how ambitious they seem to be and how duplicitous they may or may not be.

That possibility for deceit is something we are quite obsessed with for female candidates. The possibility of lies by the female is that much more powerful than the outright, absolute fact of deceit by a male candidate or leader. That is very interesting to me. The female is assumed to be a liar, but when a man lies he’s doing it for a reason and he’s on my side so I’m cool with it.

We’ve been discussing racism for some time but we do not discuss our hostility towards females in power. Unless we start to talk about it and openly discuss it, it won’t change.

Photo of a UCLA Chemistry lab

41 UCLA scientists among world’s most influential scholars, based on citations

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Photo of a UCLA Chemistry lab

A UCLA chemistry lab. The Clarivate report identifies researchers whose publications have “been repeatedly judged by their peers to be of notable significance and utility.”

 

The world’s most influential scientific researchers in 2018 include 41 UCLA scholars.

In its annual list, Clarivate Analytics names the most highly cited researchers — those whose work was most often referenced by other scientific research papers for the preceding decade in 21 fields across the sciences and social sciences. (The 2018 list is based on citations between 2006 and 2016.)

The researchers rank in the top 1 percent in their fields in producing widely cited studies, indicating that their work “has been repeatedly judged by their peers to be of notable significance and utility,” according to Clarivate. Current UCLA faculty members and researchers who were named to the list, noted with their primary UCLA research field or fields, are:

Three UCLA professors awarded 2019 Sloan Research Fellowships

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Three young UCLA professors have been named recipients of 2019 Sloan Research Fellowships. The fellowships, which were announced today, were awarded to 126 scientists and scholars from 57 colleges and universities in the United States and Canada.

“Sloan Research Fellows are the best young scientists working today,” said Adam Falk, president of the Alfred P. Sloan Foundation. “Sloan Fellows stand out for their creativity, for their hard work, for the importance of the issues they tackle and the energy and innovation with which they tackle them. To be a Sloan Fellow is to be in the vanguard of 21st-century science.”

Winners of Sloan Research Fellowships receive a two-year, $70,000 award to support their research. The fellowships are intended to enhance the careers of exceptional young scientists and scholars in chemistry, computer science, economics, mathematics, computational and evolutionary molecular biology, neuroscience, ocean sciences and physics.

UCLA’s 2019 recipients are:

 

Photo of Denis Chertverikov

Denis Chertverikov

Denis Chetverikov

Chetverikov, an assistant professor of economics at UCLA since 2013, studies econometrics, an area of economics that focuses on the use of mathematical and statistical methods to describe economic systems. His recent research includes work on high-dimensional models, shape restrictions and applications of empirical process theory in econometrics. He has been published in Econometrica, the Annals of Statistics, and the Annals of Probability. He is also the recipient of a 2016 grant from the National Science Foundation; and the MIT Presidential Fellowship in 2008. He received his doctorate in economics from the Massachusetts Institute of Technology in 2013 and his master’s from the New Economic School in Moscow in 2007.

 

 

Photo of Yongjie Hu

Yongjie Hu

Yongjie Hu

Hu, an assistant professor of mechanical and aerospace engineering, studies nanoscale transport processes and advanced materials for research into energy and micro/nanoscale sensor systems. His group’s discovery of the world’s most efficient semiconductor material for thermal management was featured in the Aug. 10, 2018 issue of the journal Science. His research has been recognized with a National Science Foundation’s CAREER Award, U.S. Air Force Young Investigator Award, and the American Chemical Society’s Doctoral New Investigator Award. Hu and colleagues also received a UCLA Sustainable LA Grand Challenge grant, a program made possible by the Anthony and Jeanne Pritzker Family Foundation. Hu joined the UCLA Samueli School of Engineering in 2014. Prior to UCLA, he was a Battelle postdoctoral fellow at MIT and earned his doctorate from Harvard University.

 

 

Aaswath Raman

Photo of Aaswath Raman

Aaswath Raman

Raman, an assistant professor of materials science and engineering, investigates how to control light and heat at the nanoscale. His laboratory brings together a multi-disciplinary computational and experimental perspective to design, fabricate and study metamaterials and new complex optical materials that can shape, absorb and emit light in highly unusual and useful ways over a broad range of wavelengths. Raman and his team are strongly motivated by climate change and the need for new energy technologies that better harness the light and heat around us. He has pioneered the development of radiative sky cooling as a new energy technology, showing how a natural phenomenon in which heat dissipates into the sky and space can, among other things, cool buildings without using electricity, and also generate electricity at night. In 2018, Raman gave a widely viewed TED talk on his research. His honors include being named to MIT Technology Review’s annual Innovators Under 35 list. He is a recipient of the Sir James Lougheed Award of Distinction from the Government of Alberta, Canada; the SPIE Green Photonics Award; and the inaugural Nelson “Buck” Robinson Science and Technology Award for Renewable Energy from the Materials Research Society. Raman is also the co-founder and chief scientific officer of SkyCool Systems, a startup company based on his radiative sky cooling research.

Photo of Lynn Vavreck

Political science professor’s new bestseller illuminates America’s ‘Identity Crisis’

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Photo of Lynn Vavreck

Lynn Vavreck

For almost a decade, UCLA political science professor Lynn Vavreck has been telling us the message matters when it comes to American politics, specifically presidential campaigns.

“Every election will create narratives about how the winner won,” said Vavreck, co-author of a recently released bestseller about the 2016 presidential election that uses data-driven analysis to dispel popular misconceptions about why Donald Trump defeated Hillary Clinton.

“But it’s common that those narratives don’t quite hold up under scrutiny when we look at polling data and electorate surveys and other data, and that’s particularly true of what we found when we looked closely at 2016,” said Vavreck, who was named the Marvin Hoffenberg Professor of American Politics and Public Policy in January.

In “Identity Crisis: The 2016 Presidential Campaign and the Battle for the Meaning of America,”Vavreck and co-authors John Sides, professor of political science at George Washington University, and Michael Tesler, associate professor of political science at UC Irvine, methodically outline the primary battles that led to the eventual matchup between Trump and Clinton. The authors dissect media coverage, national polling, data about voters’ attitudes, the effects of Russian interference, the impact of social media on misinformation and the candidates’ messaging and overarching campaign strategies.

As the nation recalibrates after a contentious midterm election season punctuated by polarized rhetoric and high voter turnout, “Identity Crisis” takes a microscope to what mattered most in 2016.

While historically presidential elections are almost always a referendum on the party in power, and typically a referendum on how well the economy is performing under that power, it’s not ever solely about the economy, Vavreck contends, and which she outlined in her 2009 book “The Message Matters: The Economy and Presidential Campaigns.”

For the most recent election, which was always going to be a toss-up, as “Identity Crisis” painstakingly documents, the message that emerged was all about identity.

Photo of the bestseller "Identity Crisis"

“Identity Crisis” cover

“In 2016, the notion of identity, and how people think about their group compared to other groups was a prism that refracted voters’ ideas about the economy, which created a phenomenon we call ‘racialized economics,” Vavreck said.

Trump was particularly good at identifying and stoking the flames of in-group/out-group insecurities and flash points, with fiery rhetoric around complicated issues like immigration, criminal justice and fears of Islamic terrorism, as well as economic anxiety. Shortly after the election, a prevailing theme of voter rage and frustration began to emerge to explain Trump’s win.

But, according to Vavreck and her co-authors and the data they examined, voters weren’t markedly angrier in 2016 than they were in 2012 or even 2008. And, voters’ attitudes about race weren’t much different between those election time frames, either.

What was different in 2016 was the message, the players, and the fact that “outsider” Trump was willing to tap into racial fears and attitudes in ways that previous Republican nominees John McCain and Mitt Romney, both of whom campaigned against a black candidate, declined to do, Vavreck said.

“I think Trump is not held to the same standards as ‘professional’ politicians because of who he is — so in some way, he was able to do what a typical politician could not do — or certainly would not do,” she said.

This identity messaging strategy was again in play during the recent midterms when the president frequently held up a caravan of asylum seekers from Central America as a national threat while speaking in support of Republican candidates.

Meanwhile, although almost every week there’s a news story about Facebook’s effects on elections and democracies, Vavreck is doubtful about how much impact the social networking platform truly wields, mostly because of the nature of the interaction on the site. People mostly follow and see posts from people who already think very similarly to them.

And the oft-discussed Russian ads were seen by a relatively small number of people, and mostly within those echo chambers, Vavreck said.

“I’m pretty skeptical of the social media angle because of the self-selection into conversations on those media,” she said.

Vavreck has emerged as a respected voice in the world of presidential politics. She contributes regularly to the New York Times data-driven politics and economics blog “The Upshot,” and is a coveted local, national and international commentator on American presidential campaigns.

She’s already thinking about what 2020 will bring, this time planning to write a book on her own, without her collaborators from “Identity Crisis.” Along with Sides, she co-wrote the well-received “The Gamble:Choice and Chance in the 2012 Presidential Election.”

“I am really interested in the role of ‘authenticity’ in politics — what it is, how we can measure it, how people perceive it, whether it really does any work,” she said. “People evaluate art and music this way all the time, and I’d like to try to evaluate politicians as performers in this way.”

Indonesia’s devastating 2018 earthquake was a rare ‘supershear,’ according to UCLA-led study

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Photo of the aftermath of the earthquake that struck the Indonesian island of Sulawesi last September

In supershear quakes, the rupture moves faster than the shear waves, which produces more energy in a shorter time making superhsears unusually destructive.

The devastating 7.5 magnitude earthquake that struck the Indonesian island of Sulawesi last September was a rare “supershear” earthquake, according to a study led by UCLA researchers.

Only a dozen supershear quakes have been identified in the past two decades, according to Lingsen Meng, UCLA’s Leon and Joanne V.C. Knopoff Professor of Physics and Geophysics and one of the report’s senior authors. The new study was published Feb. 4 in the journal Nature Geoscience.

Meng and a team of scientists from UCLA, France’s Geoazur Laboratory, JPL/Caltech, and the Seismological Laboratory at Caltech analyzed the speed, timing and extent of the Palu earthquake. Using high-resolution observations of the seismic waves caused by the temblor, along with satellite radar and optical images, they found that the earthquake propagated unusually fast, which identified it as a supershear.

Supershear earthquakes are characterized by the rupture in the earth’s crust moving very fast along a fault, causing the up-and-down or side-to-side waves that shake the ground — called seismic shear waves — to intensify. Shear waves are created in standard earthquakes, too, but in supershear quakes, the rupture moving faster than the shear waves produces more energy in a shorter time, which is what makes supershears even more destructive.

“That intense shaking was responsible for the widespread landslides and liquefactions [the softening of soil caused by the shaking, which often causes buildings to sink into the mud] that followed the Palu earthquake,” Meng said.

In fact, he said, the vibrations produced by the shaking of supershear earthquakes is analogous to the sound vibrations of the sonic boom produced by supersonic jets.

Photo of Lingsen Meng

Lingsen Meng

UCLA graduate student Han Bao, the report’s first author, gathered publicly available ground-motion recordings from a sensor network in Australia — about 2,500 miles away from where the earthquake was centered — and used a UCLA-developed source imaging technique that tracks the growth of large earthquakes to determine its rupture speed. The technique is similar to how a smartphone user’s location can be determined by triangulating the times that phone signals arrive at cellphone antenna towers.

“Our technique uses a similar idea,” Meng said. “We measured the delays between different seismic sensors that record the seismic motions at set locations.”

The researchers could then use that to determine the location of the rupture at different times during the earthquake.

They determined that the minute-long quake moved away from the epicenter at 4.1 kilometers per second (or about 2.6 miles per second), faster than the surrounding shear-wave speed of 3.6 kilometers per second (2.3 miles per second). By comparison, non-shear earthquakes move at about 60 percent of that speed — around 2.2 kilometers per second (1.3 miles per second), Meng said.

Previous supershear earthquakes — like the magnitude 7.8 Kunlun earthquake in Tibet in 2001 and the magnitude 7.9 Denali earthquake in Alaska in 2002 — have occurred on faults that were remarkably straight, meaning that there were few obstacles to the quakes’ paths. But the researchers found on satellite images of the Palu quake that the fault line had two large bends. The temblor was so strong that the rupture was able to maintain a steady speed around these bends.

That could be an important lesson for seismologists and other scientists who assess earthquake hazards.

“If supershear earthquakes occur on nonplanar faults, as the Palu earthquake did, we have to consider the possibility of stronger shaking along California’s San Andreas fault, which has many bends, kinks and branches,” Meng said.

Supershear earthquakes typically start at sub-shear speed and then speed up as they continue. But Meng said the Palu earthquake progressed at supershear speed almost from its inception, which would imply that there was high stress in the rocks surrounding the fault — and therefore stronger shaking and more land movement in a compressed amount of time than would in standard earthquakes.

“Geometrically irregular rock fragments along the fault plane usually act as barriers preventing earthquakes,” Meng said. “However, if the pressure accumulates for a long time — for decades or even hundreds of years — an earthquake will eventually overcome the barriers and will go supershear right away.”

Among the paper’s other authors are Tian Feng, a UCLA graduate student, and Hui Huang, a UCLA postdoctoral scholar. The UCLA researchers were supported by the National Science Foundation and the Leon and Joanne V.C. Knopoff Fund. The other authors are Cunren Liang of the Seismological Laboratory at Caltech; Eric Fielding and Christopher Milliner of JPL/Caltech and Jean-Paul Ampuero of Geoazur.