It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Pope Francis greets participants in a Vatican consultation, titled "Care is Work, Work is Care," as he arrives for a meeting at the Vatican May 8, 2024. (CNS/Vatican Media)
While the forces of a market economy may obstruct people from advancing social justice, society cannot remain mute in the face of unjust labor practices and exploitative economic structures, Pope Francis said.
Modern society runs the risk of "passively accepting what happens around us with a certain indifference or because we are not in a condition to understand often complex problems and find adequate responses to them," he said May 8.
The pope encouraged academics, employers, workers' organizations, and faith-based actors participating in a Vatican consultation on developing fair labor practices to "focus on the relationship between dignified work and social justice."
"This expression, 'social justice,' that came about in the social encyclicals of the popes, is a word that is not accepted by the liberal, leading economy," he said.
Organized by “The Future of Work, Labor after Laudato Si’” project, the International Catholic Migration Commission and the Dicastery for Promoting Integral Human Development, the three-day consultation brought 60 participants to Rome from around the world to discuss the dignity of work, environmental transition, migration and social justice.
In his address opening the consultation May 8, Cardinal Michael Czerny, dicastery prefect, urged participants to adopt a "synodal" approach to their discussions, which could see "unlikely allies emerge" united behind the common good.
Francis told the participants that working conditions must be considered in light of the environmental impact of labor, noting in particular how extractive industries export raw materials "for the sole purpose of satisfying the markets of the industrialized North" but often produce dangerous working conditions, "including mercury or sulfur dioxide pollution in mines."
The pope also addressed the problem of global food scarcity, especially in regions affected by war such as Gaza and Sudan, which he said is caused by extreme weather linked to climate change and exacerbated by "structural weaknesses such as poverty, high dependence on food imports and precarious infrastructure."
He added that society cannot forget about the relationship of dignified work and migration.
Due to "prejudice and inaccurate or ideological information," he said, migrants "are often viewed as a problem and a burden on a nation's costs, when in reality, by working, they contribute to the economic and social development of the country that receives them and the one they come from" by sending money back to their families.
Migration also helps wealthy nations handle the "very grave problem" caused by falling fertility rates, the pope said, but often migrants remain excluded from their full rights in those countries, including by having no access to healthcare, financial protections and social services.
Source: Originally published by Z. Feel free to share widely. Activists of all ages peacefully protesting the 2023 North American Gas Forum in Washington DC are surrounded by police. They continue chanting, playing music, and holding their banners in resistance. | Photo Courtesy of Extinction Rebellion DC
April 30 is a day I remember because it is my mom’s birthday. She died in 2005. But it’s also a day I remember because, on that day in 1971, while serving what turned out to be an 1l-month sentence in federal prison for my draft resistance activism against the Vietnam war, I was indicted with seven others by the Nixon Justice Department for a supposed conspiracy to destroy heating tunnels under DC and kidnap Henry Kissinger.
Those charges were bogus; when they finally got to a jury in conservative Harrisburg, Pa., they were hung 10-2 for acquittal, and that was the end of that particular “conspiracy” trial during the Vietnam War.
It is inspiring that on that April 30 day yesterday, several hundred people were arrested around the country, mainly students, as part of the massive worldwide movement to stop the Gaza genocide and end this war. And I saw an email just a couple hours ago from someone reminding people that on this same day in 1975, the United States military completely vacated Vietnam. This brought to an end the 30-year US effort to take over the colonizing and repressive role France had played for almost a century.
Here are some personal reflections on all of this:
-There is a level of intensity on the issue of the Gaza war that is very similar to the level of intensify many of us felt as young people during the Vietnam War, for good reason. When the daily body count is in the hundreds (Vietnam) and literal genocide—“ethnic cleansing” Bernie called it—is taking place in Gaza, intense and focused action is absolutely appropriate.
-Many of us who were students who took part in the Black Freedom and/or Anti-Vietnam War movements felt so deeply about these issues that some of us left school and we and others found a way to make a living while being a dedicated organizer for revolutionary change. Frankly, to have hope of success in our people’s movement for human and ecological survival and just and truly democratic societies, we need more young people to consciously take this step.
-It is clear that the overwhelming number of young people taking part in this spring justice uprising are doing so with a peaceful, if angry, spirit. Much of corporate media is spinning it very differently, painting the movement as violent and abusive. It is a responsibility of all of us to criticize these inaccurate characterizations and demand that the truth be reported.
-The dominant forces in the Democratic Party, and of course Republicans, really don’t like to have their policies criticized or their political power undercut by those of us willing to speak truth to power. Democrats respond one way when that happens, Republicans are much harsher. That’s been true for a very long time. As I wrote in my book Burglar for Peace, “The Nixon Administration that was in power 50-plus years ago was a repressive government, known for illegal wiretapping, inflammatory rhetoric, criminal prosecutions of peace and justice activists, and outright physical attacks, including killings, against Black Panther Party members. I had followed the Chicago 8 trial a year and a half before, a clear case of government repression against anti-war and Black Freedom activists, following the police riots during the Democratic National Convention in 1968.”
The years 1969 to 1974, when Nixon was President, were very rough for a lot of us, although most of us survived.
-The conditions for organizing are much more positive under Democrats than under Republicans. This would be particularly the case if Trump is elected this November. He and the Republicans have made clear that they have every intention of taking this country so far backward that the Biden Presidency would come to be seen as a very good four years. It’s not. Some things are good, yes, but some things aren’t, Gaza in particular right now. But compared to a Trump Presidency, it would be like night and day.
So as we keep fighting for a ceasefire and an end to the war and movement toward true Palestinian self-determination for that long-suffering people, let’s be sure to respond to the US electoral process accordingly. Trump and the MAGA Republicans must be defeated. Strong progressive candidates like The Squad need to be supported.
It’s all of one, multi-colored piece. Si, se puede.
Ted Glick has devoted his life to the progressive social change movement. After a year of student activism as a sophomore at Grinnell College in Iowa, he left college in 1969 to work full time against the Vietnam War. As a Selective Service draft resister, he spent 11 months in prison. In 1973, he co-founded the National Committee to Impeach Nixon and worked as a national coordinator on grassroots street actions around the country, keeping the heat on Nixon until his August 1974 resignation. Since late 2003, Ted has played a national leadership role in the effort to stabilize our climate and for a renewable energy revolution. He was a co-founder in 2004 of the Climate Crisis Coalition and in 2005 coordinated the USA Join the World effort leading up to December actions during the United Nations Climate Change conference in Montreal. In May 2006, he began working with the Chesapeake Climate Action Network and was CCAN National Campaign Coordinator until his retirement in October 2015. He is a co-founder (2014) and one of the leaders of the group Beyond Extreme Energy. He is President of the group 350NJ/Rockland, on the steering committee of the DivestNJ Coalition and on the leadership group of the Climate Reality Check network.
Monday, April 29, 2024
S. Korea, Cuba Agree to Open Diplomatic Missions
YOU READ THAT RIGHT
Written: 2024-04-29
Photo : YONHAP News
South Korea and Cuba, which established diplomatic ties in February, have agreed to set up diplomatic missions in Seoul and Havana.
Seoul’s foreign ministry said on Sunday that a government delegation led by Song Si-jin, director general for planning and management at the ministry, visited Cuba from Wednesday through Saturday and reached the agreement with Cuban officials.
The ministry said the two sides agreed to establish permanent embassies in Seoul and Havana, respectively, and exchanged diplomatic letters to that effect.
The ministry added that based on the agreement, it plans to continue discussions with Cuba to open a South Korean embassy in Havana as soon as possible.
The government plans to set up a temporary office in Havana and dispatch officials who will prepare for the establishment of an embassy.
Iran, Cuba mull over building ships for South American states
TEHRAN, Apr. 29 (MNA) – The head of Iran's Ports and Maritime Organization (PMO) has said that Iran and Cuba have held talks on ship construction, with the aim of utilizing domestic capacity to meet the needs of South American countries.
Providing more details about the accomplishments of Iran's Ports and Maritime Organization in the last year, Ali-Akbar Safaei mentioned that the country invested 100 trillion tomans in the construction and infrastructure of ports, with 50 trillion tomans coming from government funds and 55 trillion tomans from private sector investments. Out of this investment, 13 trillion tomans is ready to be utilized.
Referring to Iranian President Ebrahim Raeisi's emphasis on strengthening foreign trade with friendly countries, he added that the continued maritime transport interactions with Venezuela and other South American countries are always underway.
Safaei further stated that Iran's shipbuilding industry is globally renowned. For instance, Venezuela had ordered three ships of 90,000 tons, which were successfully built and delivered by Iran's skilled engineers.
He said that Iran and Cuba have held talks on ship construction, with the aim of utilizing domestic capacity to meet the needs of South American countries.
In terms of trade with Caspian Sea countries, he added that Iran achieved a record of 9 million tons, marking an impressive 30 percent growth, particularly with Russia and Kazakhstan.
AMK/6091444
Wednesday, April 24, 2024
Making diamonds at ambient pressure
Scientists develop novel liquid metal alloy system to synthesize diamond under moderate conditions
GROWTH OF DIAMOND IN LIQUID METAL ALLOY UNDER 1 ATMOSPHERE PRESSURE. (A) A PHOTO SHOWING THE AS-GROWN DIAMOND ON THE SOLIDIFIED LIQUID METAL SURFACE. (B) AN OPTICAL IMAGE OF THE AS-GROWN CONTINUOUS DIAMOND FILM ON THE SOLIDIFIED LIQUID METAL SURFACE. (C) AN OPTICAL IMAGE OF THE AS-TRANSFERRED DIAMOND FILM ON A QUANTIFOIL HOLEY AMORPHOUS CARBON FILM COATED CU TEM GRID. (D) AN ATOMIC FORCE MICROSCOPY TOPOGRAPHIC IMAGE OF THE AS-TRANSFERRED DIAMOND FILM ON THE CU TEM GRID. (E) A CROSS-SECTION TEM IMAGE OF AN AS-GROWN SINGLE DIAMOND PARTICLE ON THE SOLIDIFIED LIQUID METAL SURFACE. (F) AN ATOMIC RESOLUTION TEM IMAGE OF THE AS-GROWN DIAMOND. (G) A SCANNING ELECTRON MICROSCOPY IMAGE SHOWING A GROWN DIAMOND (PARTIALLY) SUBMERGED IN THE SOLIDIFIED LIQUID METAL. (H) SCHEME SHOWING THE DIFFUSION OF CARBON THAT LEADS TO THE GROWTH OF DIAMOND AT THE BOTTOM SURFACE OF THE LIQUID METAL.
Did you know that 99% of synthetic diamonds are currently produced using high-pressure and high-temperature (HPHT) methods?[2] A prevailing paradigm is that diamonds can only be grown using liquid metal catalysts in the gigapascal pressure range (typically 5-6 GPa, where 1 GPa is about 10,000 atm), and typically within the temperature range of 1300-1600 °C. However, the diamonds produced using HPHT are always limited to sizes of approximately one cubic centimeter due to the components involved. That is—achieving such high pressures can only be done at a relatively small length scale. Discovering alternative methods to make diamonds in liquid metal under milder conditions (particularly at lower pressure) is an intriguing basic science challenge that if achieved could revolutionize diamond manufacturing. Could the prevailing paradigm be challenged?
A team of researchers led by Director Rod RUOFF at the Center for Multidimensional Carbon Materials (CMCM) within the Institute for Basic Science (IBS), including graduate students at the Ulsan National Institute of Science and Technology (UNIST), have grown diamonds under conditions of 1 atmosphere pressure and at 1025 °C using a liquid metal alloy composed of gallium, iron, nickel, and silicon, thus breaking the existing paradigm. The discovery of this new growth method opens many possibilities for further basic science studies and for scaling up the growth of diamonds in new ways.
Director Ruoff, who is also a UNIST Distinguished Professor notes, “This pioneering breakthrough was the result of human ingenuity, unremitting efforts, and the concerted cooperation of many collaborators.” Researchers led by Ruoff conducted a series of experiments, involving several hundred parameter adjustments and a variety of experimental approaches before they finally succeeded in growing diamonds using a ‘home-built’ cold-wall vacuum system.
Ruoff notes “We had been running our parametric studies in a large chamber (named RSR-A with an interior volume of 100 liters) and our search for parameters that would yield growth of diamond was slowed due to the time needed to pump out air (about 3 minutes), purge with inert gas (90 minutes), followed by pumping down again to vacuum level (3 minutes) so that the chamber could then be filled with 1 atmosphere pressure of quite pure hydrogen/methane mixture (again 90 minutes); that is over 3 hours before the experiment could be started! I asked Dr. Won Kyung SEONG to design & build a much smaller chamber to greatly reduce the time needed to start (and finish!) the experiment with the liquid metal exposed to the mixture of methane and hydrogen.” Seong adds, “Our new homebuilt system (named RSR-S, with an interior volume of only 9 liters) can be pumped out, purged, pumped out, and filled with methane/hydrogen mixture, in a total time of 15 minutes. Parametric studies were greatly accelerated, and this helped us discover the parameters for which diamond grows in the liquid metal!”
The team discovered that diamond grows in the sub-surface of a liquid metal alloy consisting of a 77.75/11.00/11.00/0.25 mix (atomic percentages) of gallium/nickel/iron/silicon when exposed to methane and hydrogen under 1 atm pressure at ~1025 °C.
Yan GONG, UNIST graduate student and first author, explains “One day with the RSR-S system when I ran the experiment and then cooled down the graphite crucible to solidify the liquid metal, and removed the solidified liquid metal piece, I noticed a ‘rainbow pattern’ spread over a few millimeters on the bottom surface of this piece. We found out that the rainbow colors were due to diamonds! This allowed us to to identify parameters that favored the reproducible growth of diamond.”
The initial formation occurs without the need for diamond or other seed particles commonly used in conventional HPHT and chemical vapor deposition synthesis methods. Once formed, the diamond particles merge to form a film, which can be easily detached and transferred to other substrates, for further studies and potential applications.
The synchrotron two-dimensional X-ray diffraction measurements confirmed that the synthesized diamond film has a very high purity of the diamond phase. Another intriguing aspect is the presence of silicon-vacancy color centers in the diamond structure, as an intense zero-phonon line at 738.5 nm in the photoluminescence spectrum excited by using a 532 nm laser was found.
Coauthor Dr. Meihui WANG notes, “This synthesized diamond with silicon-vacancy color centers may find applications in magnetic sensing and quantum computing.”
The research team delved deeply into possible mechanisms for diamonds to nucleate and grow under these new conditions. High-resolution transmission electron microscope (TEM) imaging on cross-sections of the samples showed about 30-40 nm thick amorphous subsurface region in the solidified liquid metal that was directly in contact with the diamonds. Coauthor Dr. Myeonggi CHOE notes, “Approximately 27 percent of atoms that were present at the top surface of this amorphous region were carbon atoms, with the carbon concentration decreasing with depth.”
Ruoff elaborates, “The presence of such a high concentration of carbon ‘dissolved’ in a gallium-rich alloy could be unexpected, as carbon is reported to be not soluble in gallium. This may explain why this region is amorphous—while all other regions of the solidified liquid metal are crystalline. This sub-surface region is where our diamonds nucleate and grow and we thus focused on it.”
Researchers exposed the Ga-Fe-Ni-Si liquid metal to the methane/hydrogen for short periods of time to try to understand the early growth stage—well prior to the formation of a continuous diamond film. They then analyzed the concentrations of carbon in the subsurface regions using time-of-flight secondary ion mass spectrometry depth profiling. After a 10-minute run, no diamond particles were evident but there were ~65 at% carbon atoms present in the region where the diamond typically grows. Diamond particles began to be found after a 15-minute run, and there was a lower subsurface C atom concentration of ~27 at%.
Ruoff explains, “The concentration of subsurface carbon atoms is so high at around 10 minutes that this time exposure is close to or at supersaturation, leading to the nucleation of diamonds either at 10 minutes or sometime between 10 and 15 minutes. The growth of diamond particles is expected to occur very rapidly after nucleation, at some time between about 10 minutes and 15 minutes.”
The temperature in 27 different locations in the liquid metal was measured with an attachment to the growth chamber having an array of nine thermocouples that was designed and built by Seong. The central region of the liquid metal was found to be at a lower temperature compared to the corners and sides of the chamber. It is thought that this temperature gradient is what drives carbon diffusion towards the central region, facilitating diamond growth.
The team also discovered that silicon plays a critical role in this new growth of diamond. The size of the grown diamonds becomes smaller and their density higher as the concentration of silicon in the alloy was increased from the optimal value. Diamonds could not be grown at all without the addition of silicon, which suggests that silicon may be involved in the initial nucleation of diamond.
This was supported by the various theoretical calculations conducted to uncover the factors that may be responsible for the growth of diamonds in this new liquid metal environment. Researchers found that silicon promotes the formation and stabilization of certain carbon clusters by predominantly forming sp3 bonds like carbon. It is thought that small carbon clusters containing Si atoms might serve as the ‘pre-nuclei’, which can then grow further to nucleate a diamond. It is predicted that the likely size range for an initial nucleus is around 20 to 50 C atoms.
Ruoff states, “Our discovery of nucleation and growth of diamond in this liquid metal is fascinating and offers many exciting opportunities for more basic science. We are now exploring when nucleation, and thus the rapid subsequent growth of diamond, happens. Also ‘temperature drop’ experiments where we first achieve supersaturation of carbon and other needed elements, followed by rapidly lowering the temperature to trigger nucleation— are some studies that seem promising to us.”
The team discovered their growth method offers significant flexibility in the composition of liquid metals. Researcher Dr. Da LUO remarks, “Our optimized growth was achieved using the gallium/nickel/iron/silicon liquid alloy. However, we also found that high-quality diamond can be grown by substituting nickel with cobalt or by replacing gallium with a gallium-indium mixture.”
Ruoff concludes, “Diamond might be grown in a wide variety of relatively low melting point liquid metal alloys such as containing one or more of indium, tin, lead, bismuth, gallium, and potentially antimony and tellurium—and including in the molten alloy other elements such as manganese, iron, nickel, cobalt and so on as catalysts, and others as dopants that yield color centers. And there is a wide range of carbon precursors available besides methane (various gases, and also solid carbons). New designs and methods for introducing carbon atoms and/or small carbon clusters into liquid metals for diamond growth will surely be important, and the creativity and technical ingenuity of the worldwide research community seem likely to me, based on our discovery, to rapidly lead to other related approaches and experimental configurations. There are numerous intriguing avenues to explore!”
This research was supported by the Institute for Basic Science and has been published in the journal Nature.
Diamonds of various morphologies as grown under different growth conditions. (a) Growth by using a liquid metal alloy of Ga/Ni/Fe/Si (77.75/11.00/11.00/0.25 at%) under methane/hydrogen (1/20 molar ratio). (b) Growth by using a liquid metal alloy of Ga/Ni/Fe/Si (77.50/11.00/11.00/0.50 at%) under methane/hydrogen (1/20 molar ratio). (c) Growth by using a liquid metal alloy of Ga/In/Ni/Fe/Si (38.88/38.87/7.33/14.67/0.25 at%) under methane/hydrogen (1/20 molar ratio). (d) Growth by using a liquid metal alloy of Ga/Ni/Fe/Si (77.75/11.00/11.00/0.25 at%) under methane/hydrogen (1/5 molar ratio).
Growth of diamond in liquid metal at 1 atm pressure
ARTICLE PUBLICATION DATE
24-Apr-2024
Monday, April 22, 2024
SPACE
Giant galactic explosion exposes galaxy pollution in action
Astronomers have produced the first high-resolution map of a massive explosion in a nearby galaxy, providing important clues on how the space between galaxies is polluted with chemical elements.
INTERNATIONAL CENTRE FOR RADIO ASTRONOMY RESEARCH
IMAGE:
GALAXY NGC 4383 EVOLVING STRANGELY. GAS IS FLOWING FROM ITS CORE AT A RATE OF OVER 200 KM/S. THIS MYSTERIOUS GAS ERUPTION HAS A UNIQUE CAUSE: STAR FORMATION.
A team of international researchers studied galaxy NGC 4383, in the nearby Virgo cluster, revealing a gas outflow so large that it would take 20,000 years for light to travel from one side to the other.
The discovery was published today in the journal Monthly Notices of the Royal Astronomical Society.
Lead author Dr Adam Watts, from The University of Western Australia node at the International Centre for Radio Astronomy Research (ICRAR), said the outflow was the result of powerful stellar explosions in the central regions of the galaxy that could eject enormous amounts of hydrogen and heavier elements.
The mass of gas ejected is equivalent to more than 50 million Suns.
“Very little is known about the physics of outflows and their properties because outflows are very hard to detect,” Dr Watts said.
“The ejected gas is quite rich in heavy elements giving us a unique view of the complex process of mixing between hydrogen and metals in the outflowing gas.
“In this particular case, we detected oxygen, nitrogen, sulphur and many other chemical elements.”
Gas outflows are crucial to regulate how fast and for how long galaxies can keep forming stars. The gas ejected by these explosions pollutes the space between stars within a galaxy, and even between galaxies, and can float in the intergalactic medium forever.
The high-resolution map was produced with data from the MAUVE survey, co-led by ICRAR researchers Professors Barbara Catinella and Luca Cortese, who were also co-authors of the study.
The survey used the MUSE Integral Field Spectrograph on the European Southern Observatoryʼs Very Large Telescope, located in northern Chile.
"We designed MAUVE to investigate how physical processes such as gas outflows help stop star formation in galaxies,” Professor Catinella said.
"NGC 4383 was our first target, as we suspected something very interesting was happening, but the data exceeded all our expectations.
“We hope that in the future, MAUVE observations reveal the importance of gas outflows in the local Universe with exquisite detail.”
MAUVE: A 6 kpc bipolar outflow launched from NGC4383, one of the most Hi-rich galaxies in the Virgo cluster
ARTICLE PUBLICATION DATE
22-Apr-2024
SwRI-led eclipse projects shed new light on solar corona
Airborne, ground-based observations provide unique data and engage the public
SOUTHWEST RESEARCH INSTITUTE
IMAGE:
ACROSS THE COUNTRY, 35 TEAMS INCLUDING MORE THAN 200 VOLUNTEERS COLLECTED ECLIPSE DATA USING TELESCOPES PROVIDED THROUGH THE SWRI-LED CITIZEN CATE 2024 EXPERIMENT. THERESA COSTILOW, CARLYN ROCAZELLA AND SUSAN AND BOB BENEDICT DONNED ECLIPSE 2024 WEAR AND ENJOYED THEMED MOON PIE TREATS WHILE OBSERVING THE APRIL 8 EVENT FROM CAMPGROUND IN KINGSVILLE, OHIO.
CREDIT: SOUTHWEST RESEARCH INSTITUTE/CITIZEN CATE 2024
SAN ANTONIO — April 22, 2024 —Teams led by Southwest Research Institute successfully executed two groundbreaking experiments — by land and air — collecting unique solar data from the total eclipse that cast a shadow from Texas to Maine on April 8, 2024. The Citizen Continental-America Telescopic Eclipse (CATE) 2024 experiment engaged more than 200 community participants in a broad, approachable and inclusive attempt to make a continuous 60-minute high-resolution movie of this exciting event. A nearly simultaneous investigation used unique equipment installed in NASA’s WB-57F research aircraft to chase the eclipse shadow, making observations only accessible from a bird’s eye view.
“Total solar eclipses are relatively rare, offering unique opportunities for scientists to study the hot atmosphere above the Sun’s visible surface,” said Dr. Amir Caspi, principal investigator of both projects. “But more than that, through CATE 2024, the eclipse offered a bonding experience between scientists and communities along the path, sharing in this incredible awe-inspiring event. We hope the public experienced a new interest in, and appreciation of, the Sun and its mysteries.”
Total solar eclipses allow scientists to view the complex and dynamic features of the Sun’s outer atmosphere in ways that aren’t possible or practical by any other means, opening new windows into our understanding of the solar corona. The faint light from the corona is usually overpowered by the intense brightness of the Sun itself, and some wavelengths of light are blocked by Earth’s atmosphere.
CATE 2024 deployed a network of 35 teams of community participants, or “citizen scientists,” representing local communities along the eclipse path, deploying a “bucket brigade” of small telescopes following the eclipse’s cross-country path. CATE 2024’s scientific objectives required measuring the polarization of light, or the orientation of oscillating light waves, in the corona.
“You are familiar with this because sometimes you wear a polarizing filter right on your face — sunglasses that filter out certain angles of polarized light,” Caspi said. “The Citizen CATE 2024 telescopes have a polarizing filter baked onto every pixel of the sensor, allowing us to measure four different angles of polarization everywhere in the corona, providing a lot more information than just measuring the brightness of the light.”
Caspi also led an airborne project to observe the corona during the eclipse from 50,000 feet. These high-altitude observations both provide measurements that can’t be made from the ground and avoid any weather-related risks. Caspi’s team deployed a new suite of sensitive, high-speed, visible-light and infrared imagers, built by the SCIFLI team at NASA’s Langley Research Center, installed in the nose cone of a WB-57 jet.
Looking at complex motion in the solar corona, at new wavelengths and with new polarization measurements, will help scientists understand why it is so hot. The corona is millions of degrees Celsius, hundreds of times hotter than the visible surface below, a curious paradox that is a longstanding scientific mystery. The corona is also one of the major sources of eruptions that cause geomagnetic storms around Earth. These phenomena damage satellites, cause power grid blackouts and disrupt communication and GPS signals, so it’s important to better understand them as the world becomes increasingly dependent on such systems.
“Combining the airborne mobile data with the CATE 2024 hour-long string of observations will provide a more complete picture of the Sun’s mysterious corona,” said SwRI co-investigator Dr. Dan Seaton, who serves as the science lead for both projects.
“Both experiments required an enormous effort and precise timing to get the data we need,” Caspi said. “I am honored and in awe of the exceptionally talented teams that worked so diligently together. I can hardly wait to dig into the data we collected.”
The SwRI-led airborne team includes scientists from the National Center for Atmospheric Research High Altitude Observatory, NASA Langley Research Center, and Predictive Sciences Inc., with collaborators at the Smithsonian Astrophysical Observatory. The SwRI-led CATE 2024 project, funded by NSF and NASA, includes scientists from the National Center for Atmospheric Research, the National Solar Observatory, the Laboratory for Atmospheric and Space Physics at the University of Colorado, and the Space Science Institute, with collaborators at New Mexico State University and the Livelihoods Knowledge Exchange Network, community leaders at Rice University, Indiana University Bloomington, and the University of Maine, and over 200 community participants in 35 communities along the eclipse path.
This high-res processed image of the April 8 eclipse shows the Sun’s corona, its outermost atmosphere, in artificial colors that indicate the polarization or orientation of the light. Citizen scientists in Dallas collected these data through the SwRI-led Citizen Continental-America Telescopic Eclipse (CATE) 2024 experiment.
CREDIT
Southwest Research Institute/Citizen CATE 2024/Ritesh Patel/Dan Seaton
These preliminary images from a new suite of sensitive, high-speed, visible-light and infrared imagers aboard one of NASA’s WB-57 jets show the corona and prominences visible during the April 8, 2024, eclipse in four wavelength ranges. Moving forward, SwRI scientists will significantly improve the images through processing and analysis of the rich and complex data.
CREDIT
Southwest Research Institute/NASA/Dan Seaton
Juno observes lava lake on Io, provides insight into Jupiter’s water abundance
In December 2023 and February 2024, NASA’s Juno spacecraft, currently in orbit around and investigating Jupiter and the Jovian system, made several close flybys of the innermost of the Galilean moons, Io. During the flybys, Juno came as close as 1,500 kilometers from the surface of Io, during which extensive data and imagery of the moon were captured.
From the imagery and data, scientists were able to make the first up-close observations of the northern latitudes of Io, as well as sharp mountains and lava lakes. Furthermore, Juno’s recent flybys of Jupiter allowed scientists to refine their understanding of Jupiter’s polar cyclones and water abundance.
Io’s lava lakes and sharp mountains
Io is known to be one of the most extreme locations in the solar system, with the moon having the most geologic/volcanic activity of any planetary body in the solar system. Io’s immense volcanic activity has been recorded by several spacecraft, with images showing large plumes of sulfur and sulfur dioxide shooting as high as 500 kilometers above the surface.
Io’s volcanism is largely due to a two-to-one mean-motion orbital resonance with Europa, and a four-to-one mean-motion orbital resonance with Ganymede — meaning that Io completes two orbits of Jupiter with every orbit of Europa, and four orbits with every one orbit of Ganymede. These resonances expand and contract the surface of Io, which then allows Jupiter’s gravity to heat the interior of the moons, providing the heating needed for Io’s extreme geologic activity.
“Io is simply littered with volcanoes, and we caught a few of them in action. We also got some great close-ups and other data on a 200-kilometer-long (127-mile-long) lava lake called Loki Patera. There is amazing detail showing these crazy islands embedded in the middle of a potentially magma lake rimmed with hot lava. The specular reflection our instruments recorded of the lake suggests parts of Io’s surface are as smooth as glass, reminiscent of volcanically created obsidian glass on Earth,” said Scott Bolton, Juno’s principal investigator.
Using the Juno data, the team was able to create two simulations that visualize the characteristics of the lava lake, Loki Patera, and sharp mountains, one of which is Steeple Mountain.
Additional data from the flyby using Juno’s Microwave Radiometer instrument (MWR) shows that Io’s surface is relatively smooth compared to the surfaces of the other three Galilean moons, which are Ganymede, Callisto, and Europa. Furthermore, MWR also found that Io’s poles are colder than the moon’s middle latitudes.
Jupiter’s pole position
Juno successfully inserted itself into orbit around Jupiter in July 2016. The original mission plans had the spacecraft deorbit into Jupiter’s atmosphere after completing 32 orbits of Jupiter, where it would ultimately burn up and disintegrate. However, with the spacecraft remaining in good condition and all of its instruments still operating as expected, NASA awarded Juno and its team a mission extension in 2021 that would have the spacecraft complete 42 additional orbits of Jupiter. Juno is expected to complete its mission extension in September 2025.
Juno’s trajectory for its mission extension brings the spacecraft closer and closer to Jupiter’s north pole with each orbit. This trajectory allows for the MWR instrument to continuously improve its resolution of the planet’s north pole, which is filled with massive polar cyclones. The new data allows scientists to compare the poles and the cyclones in multiple wavelengths, and scientists have found that not all polar cyclones are created equally.
“Perhaps the most striking example of this disparity can be found with the central cyclone at Jupiter’s north pole. It is clearly visible in both infrared and visible light images, but its microwave signature is nowhere near as strong as other nearby storms. This tells us that its subsurface structure must be very different from these other cyclones. The MWR team continues to collect more and better microwave data with every orbit, so we anticipate developing a more detailed 3D map of these intriguing polar storms,” said Juno project scientist Steve Levin of NASA’s Jet Propulsion Laboratory in California. Jupiter’s northern polar cyclones, seen in infrared by Juno.
(Credit: NASA/JPL-Caltech/SwRI/MSSS) Water abundance within Jupiter
Understanding water abundance within Jupiter is one of the primary science goals for Juno’s mission. However, the team isn’t searching for liquid water, but rather investigating the presence of oxygen and hydrogen molecules — the molecules that make up water — within Jupiter’s massive atmosphere. Getting an estimate of Jupiter’s water abundance is crucial for understanding the formation of the solar system and Jupiter.
Scientists believe that Jupiter was the first planet to form, which means it likely contains most of the gas, dust, and other cosmic material left over from the formation of the Sun and our solar system. Having insight into the abundance of different molecules and materials within the planet gives scientists the chance to record what materials were present during the formation of our solar system.
Water abundance, specifically, is important for Jupiter’s meteorology, including the flow of wind currents, and the planet’s internal structure. Scientists have been trying to measure Jupiter’s water abundance for decades, with NASA’s Galileo mission collecting one of the first datasets on Jovian water abundance in 1995 during the spacecraft’s 57-minute entry into Jupiter’s atmosphere at the end of its mission. However, Galileo’s data created more confusion than clarity, as the spacecraft found that the planet’s atmosphere was hot and void of water.
“The probe did amazing science, but its data was so far afield from our models of Jupiter’s water abundance that we considered whether the location it sampled could be an outlier. But before Juno, we couldn’t confirm. Now, with recent results made with MWR data, we have nailed down that the water abundance near Jupiter’s equator is roughly three to four times the solar abundance when compared to hydrogen. This definitively demonstrates that the Galileo probe’s entry site was an anomalously dry, desert-like region,” Bolton said.
The northern and equatorial regions of Jupiter, imaged by Juno during its 10th flyby of the planet.
(Credit: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill)
Juno’s new results on Jovian water abundance suggest very low water abundance—an unexpected result that scientists are still trying to understand. However, these results do support scientists’ theories that during the solar system’s formation, water-ice material was likely a driving force behind heavy element enrichment, the process by which chemical elements heavier than hydrogen and helium were accreted by Jupiter during its formation.
Additional data on Jovian water abundance collected by Juno during the remainder of its extended mission will help scientists compare Jupiter’s water abundance at polar regions and equatorial regions. Additional data will also help reveal the structure of the planet’s core.
Juno’s next flyby of Jupiter, the 61st of the mission, is planned for May 12. (Lead image: Image of Io taken by Juno on October 15, 2023. Credit: NASA/JPL-Caltech/SwRI/MSSS/Ted Stryk)
To find life in the universe, look to deadly Venus
Despite surface temperatures hot enough to melt lead, lava-spewing volcanoes, and puffy clouds of sulfuric acid, uninhabitable Venus offers vital lessons about the potential for life on other planets, a new paper argues.
“We often assume that Earth is the model of habitability, but if you consider this planet in isolation, we don’t know where the boundaries and limitations are,” said UC Riverside astrophysicist and paper first author Stephen Kane. “Venus gives us that.”
Published today in the journal Nature Astronomy, the paper compiles much of the known information about Earth and Venus. It also describes Venus as an anchor point from which scientists can better understand the conditions that preclude life on planets around other stars.
Though it also features a pressure cooker-like atmosphere that would instantly flatten a human, Earth and Venus share some similarities. They have roughly the same mass and radius. Given the proximity to that planet, it’s natural to wonder why Earth turned out so differently.
Many scientists assume that insolation flux, the amount of energy Venus receives from the sun, caused a runaway greenhouse situation that ruined the planet.
“If you consider the solar energy received by Earth as 100%, Venus collects 191%. A lot of people think that’s why Venus turned out differently,” Kane said. “But hold on a second. Venus doesn’t have a moon, which is what gives Earth things like ocean tides and influenced the amount of water here.”
In addition to some of the known differences, more NASA missions to Venus would help clear up some of the unknowns. Scientists don’t know the size of its core, how it got to its present, relatively slow rotation rate, how its magnetic field changed over time, or anything about the chemistry of the lower atmosphere.
“Venus doesn’t have a detectable magnetic field. That could be related to the size of its core,” Kane said. “Core size also give us information about how a planet cools itself. Earth has a mantle circulating heat from its core. We don’t know what’s happening inside Venus.”
A terrestrial planet’s interior also influences its atmosphere. That is the case on Earth, where our atmosphere is largely the result of volcanic outgassing.
NASA does have twin missions to Venus planned for the end of this decade, and Kane is assisting with both of them. The DAVINCI mission will probe the acid-filled atmosphere to measure noble gases and other chemical elements.
“DAVINCI will measure the atmosphere all the way from the top to the bottom. That will really help us build new climate models and predict these kinds of atmospheres elsewhere, including on Earth, as we keep increasing the amount of CO2,” Kane said.
The VERITAS mission, led by NASA’s Jet Propulsion Laboratory, won’t land on the surface but it will allow scientists to create detailed 3D landscape reconstructions, revealing whether the planet has active plate tectonics or volcanoes.
“Currently, our maps of the planet are very incomplete. It’s very different to understand how active the surface is, versus how it may have changed through time. We need both kinds of information,” Kane said.
Ultimately, the paper advocates for missions like these to Venus for two main reasons. One is the ability, with better data, to use Venus to ensure inferences about life on farther-flung planets are correct.
“The sobering part of the search for life elsewhere in the universe is that we’re never going to have in situ data for an exoplanet. We aren’t going there, landing, or taking direct measurements of them,” Kane said.
“If we think another planet has life on the surface, we might not ever know we’re wrong, and we’d be dreaming about a planet with life that doesn’t have it. We are only going to get that right by properly understanding the Earth-size planets we can visit, and Venus gives us that chance.”
The other reason to research Venus is that it offers a preview of what Earth’s future could look like.
“One of the main reasons to study Venus is because of our sacred duties as caretakers of this planet, to preserve its future. My hope is that through studying the processes that produced present-day Venus, especially if Venus had a more temperate past that’s now devastated, there are lessons there for us. It can happen to us. It’s a question of how and when,” Kane said.
Venus as an Anchor Point for Planetary Habitability
ARTICLE PUBLICATION DATE
22-Apr-2024
AI and physics combine to reveal the 3D structure of a flare erupting around a black hole
CALIFORNIA INSTITUTE OF TECHNOLOGY
VIDEO:
BASED ON RADIO TELESCOPE DATA AND MODELS OF BLACK HOLE PHYSICS, A TEAM LED BY CALTECH HAS USED NEURAL NETWORKS TO RECONSTRUCT A 3D IMAGE THAT SHOWS HOW EXPLOSIVE FLARE-UPS IN THE DISK OF GAS AROUND OUR SUPERMASSIVE BLACK HOLE, SAGITTARIUS A* (SGR A*), MIGHT LOOK.
THE 3D FLARE STRUCTURE FEATURES TWO BRIGHT, COMPACT FEATURES LOCATED ABOUT 75 MILLION KILOMETERS (OR HALF THE DISTANCE BETWEEN EARTH AND THE SUN) FROM THE CENTER OF THE BLACK HOLE. IT IS BASED ON DATA COLLECTED BY THE ATACAMA LARGE MILLIMETER ARRAY (ALMA) IN CHILE AFTER AN ERUPTION SEEN IN X-RAY DATA ON APRIL 11, 2017.
HERE, THE RECONSTRUCTED 3D STRUCTURE IS SEEN FROM A FIXED ANGLE AS THE MODEL EVOLVES OVER A SPAN OF ABOUT 100 MINUTES, SHOWING THE PATH THE TWO BRIGHT FEATURES TRACE AROUND THE BLACK HOLE.
CREDIT: A. LEVIS/A. CHAEL/K. BOUMAN/M. WIELGUS/P. SRINIVASAN
Scientists believe the environment immediately surrounding a black hole is tumultuous, featuring hot magnetized gas that spirals in a disk at tremendous speeds and temperatures. Astronomical observations show that within such a disk, mysterious flares occur up to several times a day, temporarily brightening and then fading away. Now a team led by Caltech scientists has used telescope data and an artificial intelligence (AI) computer-vision technique to recover the first three-dimensional video showing what such flares could look like around Sagittarius A* (Sgr A*, pronounced sadge-ay-star), the supermassive black hole at the heart of our own Milky Way galaxy.
The 3D flare structure features two bright, compact features located about 75 million kilometers (or half the distance between Earth and the Sun) from the center of the black hole. It is based on data collected by the Atacama Large Millimeter Array (ALMA) in Chile over a period of 100 minutes directly after an eruption seen in X-ray data on April 11, 2017.
"This is the first three-dimensional reconstruction of gas rotating close to a black hole," says Katie Bouman, assistant professor of computing and mathematical sciences, electrical engineering and astronomy at Caltech, whose group led the effort described in a new paper in Nature Astronomy.
Aviad Levis, a postdoctoral scholar in Bouman's group and lead author on the new paper, emphasizes that while the video is not a simulation, it is also not a direct recording of events as they took place. "It is a reconstruction based on our models of black hole physics. There is still a lot of uncertainty associated with it because it relies on these models being accurate," he says.
Using AI informed by physics to figure out possible 3D structures
To reconstruct the 3D image, the team had to develop new computational imaging tools that could, for example, account for the bending of light due to the curvature of space-time around objects of enormous gravity, such as a black hole.
The multidisciplinary team first considered if it would be possible to create a 3D video of flares around a black hole in June 2021. The Event Horizon Telescope (EHT) Collaboration, of which Bouman and Levis are members, had already published the first image of the supermassive black hole at the core of a distant galaxy, called M87, and was working to do the same with EHT data from Sgr A*. Pratul Srinivasan of Google Research, a co-author on the new paper, was at the time visiting the team at Caltech. He had helped develop a technique known as neural radiance fields (NeRF) that was then just starting to be used by researchers; it has since had a huge impact on computer graphics. NeRF uses deep learning to create a 3D representation of a scene based on 2D images. It provides a way to observe scenes from different angles, even when only limited views of the scene are available.
The team wondered if, by building on these recent developments in neural network representations, they could reconstruct the 3D environment around a black hole. Their big challenge: From Earth, as anywhere, we only get a single viewpoint of the black hole.
The team thought that they might be able to overcome this problem because gas behaves in a somewhat predictable way as it moves around the black hole. Consider the analogy of trying to capture a 3D image of a child wearing an inner tube around their waist. To capture such an image with the traditional NeRF method, you would need photos taken from multiple angles while the child remained stationary. But in theory, you could ask the child to rotate while the photographer remained stationary taking pictures. The timed snapshots, combined with information about the child's rotation speed, could be used to reconstruct the 3D scene equally well. Similarly, by leveraging knowledge of how gas moves at different distances from a black hole, the researchers aimed to solve the 3D flare reconstruction problem with measurements taken from Earth over time.
With this insight in hand, the team built a version of NeRF that takes into account how gas moves around black holes. But it also needed to consider how light bends around massive objects such as black holes. Under the guidance of co-author Andrew Chael of Princeton University, the team developed a computer model to simulate this bending, also known as gravitational lensing.
With these considerations in place, the new version of NeRF was able to recover the structure of orbiting bright features around the event horizon of a black hole. Indeed, the initial proof-of-concept showed promising results on synthetic data.
A flare around Sgr A* to study
But the team needed some real data. That's where ALMA came in. The EHT's now famous image of Sgr A* was based on data collected on April 6–7, 2017, which were relatively calm days in the environment surrounding the black hole. But astronomers detected an explosive and sudden brightening in the surroundings just a few days later, on April 11. When team member Maciek Wielgus of the Max Planck Institute for Radio Astronomy in Germany went back to the ALMA data from that day, he noticed a signal with a period matching the time it would take for a bright spot within the disk to complete an orbit around Sgr A*. The team set out to recover the 3D structure of that brightening around Sgr A*.
ALMA is one of the most powerful radio telescopes in the world. However, because of the vast distance to the galactic center (more than 26,000 light-years), even ALMA does not have the resolution to see Sgr A*'s immediate surroundings. What ALMA measures are light curves, which are essentially videos of a single flickering pixel, which are created by collecting all of the radio-wavelength light detected by the telescope for each moment of observation.
Recovering a 3D volume from a single-pixel video might seem impossible. However, by leveraging an additional piece of information about the physics that are expected for the disk around black holes, the team was able to get around the lack of spatial information in the ALMA data.
Strongly polarized light from the flares provided clues
ALMA doesn’t just capture a single light curve. In fact, it provides several such "videos" for each observation because the telescope records data relating to different polarization states of light. Like wavelength and intensity, polarization is a fundamental property of light and represents which direction the electric component of a light wave is oriented with respect to the wave's general direction of travel. "What we get from ALMA is two polarized single-pixel videos," says Bouman, who is also a Rosenberg Scholar and a Heritage Medical Research Institute Investigator. "That polarized light is actually really, really informative."
Recent theoretical studies suggest that hot spots forming within the gas are strongly polarized, meaning the light waves coming from these hot spots have a distinct preferred orientation direction. This is in contrast to the rest of the gas, which has a more random or scrambled orientation. By gathering the different polarization measurements, the ALMA data gave the scientists information that could help localize where the emission was coming from in 3D space.
Introducing Orbital Polarimetric Tomography
To figure out a likely 3D structure that explained the observations, the team developed an updated version of its method that not only incorporated the physics of light bending and dynamics around a black hole but also the polarized emission expected in hot spots orbiting a black hole. In this technique, each potential flare structure is represented as a continuous volume using a neural network. This allows the researchers to computationally progress the initial 3D structure of a hotspot over time as it orbits the black hole to create a whole light curve. They could then solve for the best initial 3D structure that, when progressed in time according to black hole physics, matched the ALMA observations.
The result is a video showing the clockwise movement of two compact bright regions that trace a path around the black hole. "This is very exciting," says Bouman. "It didn't have to come out this way. There could have been arbitrary brightness scattered throughout the volume. The fact that this looks a lot like the flares that computer simulations of black holes predict is very exciting."
Levis says that the work was uniquely interdisciplinary: "You have a partnership between computer scientists and astrophysicists, which is uniquely synergetic. Together, we developed something that is cutting edge in both fields—both the development of numerical codes that model how light propagates around black holes and the computational imaging work that we did."
The scientists note that this is just the beginning for this exciting technology. "This is a really interesting application of how AI and physics can come together to reveal something that is otherwise unseen," says Levis. "We hope that astronomers could use it on other rich time-series data to shed light on complex dynamics of other such events and to draw new conclusions."
The new paper is titled, "Orbital Polarimetric Tomography of a Flare Near the Sagittarius A* Supermassive Black Hole." The work was supported by funding from the National Science Foundation, the Carver Mead New Adventures Fund at Caltech, the Princeton Gravity Initiative, and the European Research Council.
Viewing a Reconstructed 3D Structure Around a Black Hole From All Angles
Based on radio telescope data and models of black hole physics, a team led by Caltech has used neural networks to reconstruct a 3D image that shows how explosive flare-ups in the disk of gas around our supermassive black hole, Sagittarius A* (Sgr A*), might look.
The 3D flare structure features two bright, compact features located about 75 million kilometers (or half the distance between Earth and the Sun) from the center of the black hole. It is based on data collected by the Atacama Large Millimeter Array (ALMA) in Chile after an eruption seen in X-ray data on April 11, 2017.
Here, the reconstructed 3D structure is shown at a single time (9:20 UT), directly after a flare was detected in X-ray, with the view rotating to help visualize the structure from all angles.
CREDIT
A. Levis/A. Chael/K. Bouman/M. Wielgus/P. Srinivasan
