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)
Friday, March 26, 2021
Bringing Total Worker Health® to a multinational agribusiness in Latin America
Researchers from the Center for Health, Work & Environment (CHWE) at the Colorado School of Public Health have published a paper in the International Journal of Environmental Research and Public Health studying the effectiveness of applying Total Worker Health (TWH) in an international context. The study, led by a team at CHWE, is the first to examine how a TWH framework operates outside of a western context in Latin America workforces.
"Although recent reviews show that TWH intervention studies have had some global reach, the vast majority have been conducted in Western countries," says lead researcher Diana Jaramillo. "While global organizations, as well as governmental entities in Latin America, acknowledge the importance of this integrated approach to occupational health and safety, there are no studies exploring the implementation of the TWH approach in Latin America, to our knowledge." This region, which encompasses many low- and middle-income countries and diverse cultures, is in great need of TWH interventions to protect and promote the health of their workforce.
In the published manuscript, the researchers explored three novel concepts: the applicability of TWH theories in 1) a Latin American cultural setting; 2) a vertically integrated agribusiness; 3) within a multinational organization. The team took a community-based participatory research approach to adapt existing TWH tools and training. They convened stakeholders, interviewed health and safety champions and senior leaders, and identified TWH strategies that needed tweaking to meet the conditions of workers from very different backgrounds and with very different needs.
The case study documents the collaboration with Pantaleon, one of the largest agribusinesses in Latin America. CHWE partnered with the company in 2016 to engage in a series of projects to evaluate and address health and safety for the company's thousands of employees. One aspect was the process and adaptation strategy for conducting a TWH assessment at multiple organizational levels and in multiple countries including Guatemala, Nicaragua, and Mexico. The summary provides support for designing TWH interventions that can be adopted and implemented in global enterprise-level settings that span a diverse range of agriculture work functions from the corporate offices to the sugarcane fields.
"This case study represents a way to reach thousands of vulnerable workers in a large Latin American agribusiness and the opportunity to explore TWH research, translation and dissemination across different countries and cultures," adds Jaramillo. In the long term, they expect this approach to improve employee health, safety and well-being, and ultimately, productivity in meaningful and measurable ways.
###
About the Center for Health, Work and Environment
The Center for Health, Work and Environment (CHWE) at the Colorado School of Public Health is one of six Centers of Excellence for Total Worker Health® and houses the Mountain and Plains Education and Research Center, one of 18 centers of its kind supported by the National Institute for Occupational Safety and Health (NIOSH). Main offices for the Center are located at the University of Colorado Anschutz Medical Campus in Aurora, Colorado. The Center team works with faculty, students, and community partners on numerous projects in occupational and environmental health, safety, and well-being.
About the Colorado School of Public Health
The Colorado School of Public Health is the first and only accredited school of public health in the Rocky Mountain Region, attracting top tier faculty and students from across the country, and providing a vital contribution towards ensuring our region's health and well-being. Collaboratively formed in 2008 by the University of Colorado, Colorado State University, and the University of Northern Colorado, the Colorado School of Public Health provides training, innovative research and community service to actively address public health issues including chronic disease, access to health care, environmental threats, emerging infectious diseases, and costly injuries. Learn more and follow Colorado SPH's updates on Facebook, Twitter and Instagram.
Measurable changes in brain activity during first few months of studying a newlanguage
Improvements in reading and listening skills of first-time Japanese language students observed via brain scan
A study with first-time learners of Japanese has measured how brain activity changes after just a few months of studying a new language. The results show that acquiring a new language initially boosts brain activity, which then reduces as language skills improve.
"In the first few months, you can quantitatively measure language-skill improvement by tracking brain activations," said Professor Kuniyoshi L. Sakai, a neuroscientist at the University of Tokyo and first author of the research recently published in Frontiers in Behavioral Neuroscience.
Researchers followed 15 volunteers as they moved to Tokyo and completed introductory Japanese classes for at least three hours each day. All volunteers were native speakers of European languages in their 20s who had previously studied English as children or teenagers, but had no prior experience studying Japanese or traveling to Japan.
Volunteers took multiple choice reading and listening tests after at least eight weeks of lessons and again six to fourteen weeks later. Researchers chose to assess only the "passive" language skills of reading and listening because those can be more objectively scored than the "active" skills of writing and speaking. Volunteers were inside a magnetic resonance imaging (MRI) scanner while taking the tests so that researchers could measure local blood flow around their brain regions, an indicator of neuronal activity.
"In simple terms, there are four brain regions specialized for language . Even in a native, second or third language, the same regions are responsible," said Sakai.
Those four regions are the grammar center and comprehension area in the left frontal lobe as well as the auditory processing and vocabulary areas in the temporo-parietal lobe. Additionally, the memory areas of the hippocampus and the vision areas of the brain, the occipital lobes, also become active to support the four language-related regions while taking the tests.
During the initial reading and listening tests, those areas of volunteers' brains showed significant increases in blood flow, revealing that the volunteers were thinking hard to recognize the characters and sounds of the unfamiliar language. Volunteers scored about 45% accuracy on the reading tests and 75% accuracy on the listening tests (random guessing on the multiple choice tests would produce 25% accuracy).
Researchers were able to distinguish between two subregions of the hippocampus during the listening tests. The observed activation pattern fits previously described roles for the anterior hippocampus in encoding new memories and for the posterior hippocampus in recalling stored information.
At the second test several weeks later, volunteers' reading test scores improved to an average of 55%. Their accuracy on the listening tests was unchanged, but they were faster to choose an answer, which researchers interpret as improved comprehension.
Comparing results from the first tests to the second tests, after additional weeks of study, researchers found decreased brain activation in the grammar center and comprehension area during listening tests, as well as in the visual areas of the occipital lobes during the reading tests.
"We expect that brain activation goes down after successfully learning a language because it doesn't require so much energy to understand," said Sakai.
Notably during the second listening test, volunteers had slightly increased activation of the auditory processing area of their temporal lobes, likely due to an improved "mind's voice" while hearing.
"Beginners have not mastered the sound patterns of the new language, so cannot hold in memory and imagine them well. They are still expending a lot of energy to recognize the speech in contrast to letters or grammar rules," said Sakai.
This pattern of brain activation changes -- a dramatic initial rise during the learning phase and a decline as the new language is successfully acquired and consolidated -- can give experts in the neurobiology of language a biometric tool to assess curricula for language learners or potentially for people regaining language skills lost after a stroke or other brain injury.
"In the future, we can measure brain activations to objectively compare different methods to learn a language and select a more effective technique," said Sakai.
Until an ideal method can be identified, researchers at UTokyo recommend acquiring a language in an immersion-style natural environment like studying abroad, or any way that simultaneously activates the brain's four language regions.
This pattern of brain activation over time in individual volunteers' brains mirrors results from previous research (see Figure 3E in Science DOI: 10.1126/science.1113530) where Sakai and his collaborators worked with native Japanese-speaking 13- and 19-year-olds who learned English in standard Tokyo public school lessons. Six years of study seemed to allow the 19-year-olds to understand the second language well enough that brain activation levels reduced to levels similar to those of their native language.
The recent study confirmed this same pattern of brain activation changes over just a few months, not years, potentially providing encouragement for anyone looking to learn a new language as an adult.
"We all have the same human brain, so it is possible for us to learn any natural language. We should try to exchange ideas in multiple languages to build better communication skills, but also to understand the world better -- to widen views about other people and about the future society," said Sakai.
###
This research is a peer-reviewed, longitudinal observational study of 15 people published in Frontiers in Behavioral Neuroscience.
Research Publication
Kuniyoshi L. Sakai, Tatsuro Kuwamoto, Satoma Yagi, and Kyohei Matsuya. 26 March 2021. Modality-dependent brain activation changes induced by acquiring a second language abroad. Frontiers in Behavioral Neuroscience. DOI: 10.3389/fnbeh.2021.631957
School closures disproportionately hitdisadvantaged students in the US
A study analyzing the distribution of school closures due to COVID concludes that racial minorities, students in need and with already poor academic performance have been more likely engaged in remote schooling since September 2020
The uneven distribution of school closures in the US since September 2020 threatens to exacerbate regional, racial and class-based divides in educational performance, according to research by Zachary Parolin, of Bocconi University's Department of Social and Political Science, recently published in Nature Human Behavior. For example, in October, only 35% of White students were on distance learning, compared with 52% of Black students, 60% of Hispanic students and 65% of Asian students. And schools recording the lowest math scores were 15% more likely to be closed.
Professor Parolin and Emma Lee (Columbia University) found in fact that exposure to distance learning from September through December 2020 was more common among schools with lower academic performance (measured with third-grade math scores), a higher share of students experiencing homelessness, more students eligible for free/reduced-price lunches and from racial/ethnic minorities.
"If the schools and students with the greatest pre-COVID disadvantages are also those most exposed to school closures and distance learning, inequalities in learning outcomes may worsen," Professor Parolin says. Recent studies have demonstrated, in fact, that distance learning is less effective than traditional schooling, and that reductions in test scores appear to be particularly steep for students with less educated parents.
The authors measured in-person attendance using an anonymized mobile-phone database able to track traffic around locations, which covers 94% of US school districts and 98% of counties. A school was identified as "closed" or "mostly closed" if it experienced a 50% year-over-year decline in in-person visits during a given month.
"The race/ethnicity and math score gaps are particularly striking," Parolin and Lee write. "In October, 35% of White students were exposed to distance learning, compared with 52% of Black students, 60% of Hispanic students and 65% of Asian students. Moreover, schools recording the lowest third-grade math scores prior to the pandemic were, on average, around 15 percentage points more likely to be closed during September to December 2020 relative to schools with average test scores."
Disparities seem to be mainly driven by geography: larger and denser cities are both at greater risk of COVID spread and more diverse in population, while rural and less populated areas are more frequently white. Politics can also play a role, as Democrats (in power in denser, race-mixed areas, such as California or Washington DC) tended to be more rigorous in COVID restrictions than Republicans.
"The results of the study don't imply we are taking position on whether schools should close", Prof. Parolin warns. "School closures may save lives if they prevent the spread of COVID and the decision to turn to distance learning is undoubtedly difficult. Our study only observes that closures may be widening the educational gap."
###
CRIMINAL CAPITALI$M WORKERS COMP
Study reveals bias among doctors who classify X-rays for coal miner's black lung claims
UIC researchers first to publish data on B-reader financial conflicts of interest
University of Illinois Chicago researchers are thefirst to report on the financial conflicts of interest that exist among doctors who review the chest X-rays of coal miners who file workers' compensation claims of totally disabling disease with the U.S. Department of Labor's Federal Black Lung Program.
The UIC researchers found that the determinations of these doctors - who are known as B-readers and who are certified by the National Institute for Occupational Safety and Health, or NIOSH - were strongly associated with the party that hired them.
By analyzing 63,780 radiograph classifications made by 264 physicians in Black Lung Program claims filed during 2000-2013, the researchers found that B-readers who were identified as ever being hired by a coal miner's employer read the images as negative for pneumoconiosis in 84.8% of the records. Pneumoconiosis is the general term for a class of lung diseases caused by the inhalation of dust - coal worker's pneumonoconiosis, or CWP, is commonly known as black lung disease and caused by long-term inhalation of coal dust.
Comparatively, a lower percentage of the records were read as negative for pneumoconiosis by those hired by the Department of Labor or a miner - 63.2% and 51.3% of the records, respectively.
These results are published today in the Annals of the American Thoracic Society.
The authors write that given the clear association between classifications and financial conflicts of interest, a lack of consistency in classifications within and between B-readers and an absence of an objective gold-standard for chest X-ray classifications, substantial improvements in transparency, oversight, and objectivity for black lung claims are clearly needed.
Lee Friedman
UIC's Lee Friedman and Dr. Robert Cohen are senior authors of the study.
"Certainly, we anticipated finding some bias, as there has been anecdotal evidence for some time and the Department of Labor has even taken action since 2013 to avoid such bias. But the degree of bias shown in this data is alarming," said Friedman, associate professor of environmental and occupational health sciences at the UIC School of Public Health. "It begs the question: are those actions enough and are they helping?"
For example, NIOSH has written a rule to institute a panel to review and decertify B-readers who repeatedly provide unreasonably inaccurate classifications of X-rays. However, complaints must be submitted to NIOSH and only after three independent complaint investigations will a B-reader be decertified.
"The system we have today is not being used to its full potential and, even if it were, it still leaves a lot to be desired when it comes to ensuring accurate and judicious outcomes for all parties," said Cohen, clinical professor of environmental and occupational health sciences and director of the Mining Education and Resource Center.
The analysis also found that there were 64 B-readers who classified an absence of pneumoconiosis in 95% of their classifications, with the vast majority (93.3%) of the classifications being made by B-readers who were primarily hired by the employer. The majority of these B-readers - 51 of them - classified films as negative for pneumoconiosis in more than 99% of their classifications.
In contrast, there were 23 B-readers that diagnosed simple pneumoconiosis in 95% of their classifications, with a minority (22%) of the classifications being made by B-readers who were primarily hired by the claimant-miner; 18 of these B-readers diagnosed simple pneumoconiosis in more than 99% of their classifications.
"While there is evidence of bias on both sides, it is clear that the degree of bias is much heavier on the employer side, and this is twofold," Cohen said. "Not only are those hired by an employer much more likely to classify a chest X-ray as negative for black lung disease, but it is also much more likely that an employer will have the resources to hire its own expert - at a much higher fee - in the first place.
"It is clear from this data that this bias is a systemic problem and the most significant offenders are identifiable - the records show a clear pattern of B-reader conflicts of interest," he said.
Better utilizing the current regulations to decertify B-readers with significant bias are among the recommendations the authors of the study present in the paper.
The authors also recommend that all initial contact and payments should be made by USDOL, and the other parties should be prohibited from communicating on a claim until the initial classifications are submitted, limiting coordination between the reader and requester.
Cohen and Friedman say other methods to reduce bias could include growing and diversifying the pool of B-readers; regulating the fees of B-readers who testify on behalf of either party; mandating B-readers to disclose any wholesale relationships and their associated income from related classifications; and, investing in scientific advances that leverage artificial intelligence to classify chest films without bias.
"The technology is there, but we don't have the systems in place to validate or implement a process," Cohen said. "It's a matter of motivation."
"This is really just the tip of the iceberg," Friedman said. "It is very likely that this issue extends beyond the Federal Black Lung Program and is pervasive across workers' compensation systems."
###
UIC's Sudeshna De and Kirsten Almberg are coauthors of the paper, which noted no external funding for the research.
Physicians' financial conflicts of interest may play a role in black lung diagnoses
IMAGE: STUDY EXAMINES BLACK LUNG DISEASE DIAGNOSES AND PHYSICIANS' FINANCIAL CONFLICTS OF INTEREST.view more
CREDIT: AT
March 23, 2021-- A new study published online in the Annals of the American Thoracic Society examines if the source of physician payment for a medical opinion influences whether the physician finds that a coal miner has black lung disease. The study is the first to look at this relationship in the workers' compensation process.
In "Association Between Financial Conflicts of Interest and ILO Classifications for Black Lung Disease," Lee S. Friedman, PhD, associate professor, School of Public Health, Division of Environmental and Occupational Health Sciences, University of Illinois Chicago and colleagues looked at which party reimbursed B-readers--physicians trained and licensed by the National Institute for Occupational Safety and Health (NIOSH) and approved by the U.S. Department of Labor (USDOL) to evaluate miners' chest X-rays during workers' compensation proceedings--and correlated the payments with diagnoses of black lung disease.
"Our findings demonstrate that B-readers who were ever hired by employers were substantially less likely to classify an absence of coal workers' black lung disease (pneumoconiosis) when they were contracted by the USDOL, compared to later classifications when hired by the employer," said Dr. Friedman. "We did not observe this disparity among physicians ever hired by a miner."
These physicians are hired by the USDOL for the initial evaluation. The miner and/or employer (mine operator), at their own expense, then has the option to request a supplemental evaluation if they feel the initial USDOL-funded classification is incorrect. They may pick any B-reader they choose.
The researchers looked at 63,780 X-ray classifications made by 264 B-reader physicians between 2000 and 2013 for U.S. coal miners' black lung claims. Of these, 7,656 court decisions for the period 2002-2019 were used to evaluate financial conflict of interest for each physician.
"The more frequently a physician is hired by an employer to provide a medical opinion on workers' compensation cases for black lung disease, the more likely that physician will not identify black lung disease on a chest X-ray," said Dr. Friedman. "And the more a physician works with a miner on their claim process, the more likely they will identify black lung disease."
Dr. Friedman noted that many miners cannot afford a supplemental evaluation following the evaluation by the B-reader selected by USDOL, so, often, the only additional classification submitted to the court is from the employer. "While bias is present in both sets of physicians, a vast majority of classifications submitted to these courts are paid for by mine operators. The employers will throw a lot of resources at these cases to discourage miners from filing for compensation by making the process protracted and painful."
One-fifth of all classifications submitted to USDOL were made by physicians who classified 95 percent of their cases in one direction - absence or presence of pneumoconiosis. The average B-reader noted the presence of pneumoconiosis in a third of X-rays. The vast majority of the physicians who classified X-rays in a singular direction were hired by employers and were reporting an absence of pneumoconiosis.
These evaluations are done through the Federal Black Lung Program, which is administered by the USDOL and charged with managing claims by coal miners for workers' compensation for totally disabling coal mine dust disease (black lung disease). Earlier reports raised concerns that financial conflicts of interest may systematically bias physicians when they are classifying chest X-rays for the absence, presence or severity of black lung disease.
Dr. Friedman and his colleagues concluded that their analysis demonstrates the need to reduce subjectivity in the classification of chest X-rays for black lung disease. "There remains a need for empirical analyses specific to the workers' compensation system, which is wholly lacking," they state. "All parties involved deserve a compensation system that is objective and expeditious."
They recommend a series of systematic reforms, as discussed in the paper.
###
UPDATED
Researchers show magnetic fields around black hole in image for first time
A team of international scientists that includes a Canadian researcher said it has mapped, for the first time, the magnetic fields surrounding a black hole.
The Event Horizon Telescope Collaboration team produced an image that shows electromagnetic fields that look like a "crisp swirl" of light around the black hole as it appears in polarized light.
The discovery will help astrophysicists better understand black holes and their profound effects on galaxies, said Avery Broderick, one of the team's researchers who works at Perimeter Institute for Theoretical Physics in Waterloo, Ont.
"We’re watching this astrophysical drama, this twisting up of magnetic fields, building that spring at the bottom that’s going to launch this jet out into this large universe and rule the fates of galaxies," Broderick said in an interview.
The polarized image allows researchers to learn more about the magnetic fields surrounding the black hole in the M87 galaxy, he said.
They believe the research helps its understanding of how magnetic fields allow the black hole to "eat" matter and eject powerful energetic jets.
Two years ago the same team released the first-ever image of a black hole.
The international collaboration is composed of more than 300 researchers who compiled the image from eight Earth-based telescopes positioned around the world.
The new image is part of two related papers published Wednesday in The Astrophysical Journal.
The scientists have been working on the new project the past two years, Broderick said, ensuring what they were seeing was, in fact, real.
He said he and his team devised a new radioimaging method that helped show the electromagnetic fields.
There were five other teams that were using different methods to show the polarization, some tried and true, others novel.
"All six of these achieved very similar results," he said.
"Only when we have this kind of replication across this many teams that we feel confident we’re seeing something that’s really in the sky and not an artifact of our analysis."
What the team produced is comparable, in a sense, to the old high school experiment where students drop iron filings around a magnet bar, he explained.
The filings will line up in a unique fashion around the poles and illustrate the invisible magnetic field.
"What we have shown is those magnetic fields are not random, not just angled up in random directions, but very much like that bar magnet," said Broderick, who is also a professor at the University of Waterloo.
He said the teams produced four images between on April 5 and 11 in 2017.
"In some sense we have a polarized movie," he said. "But the movie only has four frames."
There is a difference between the first two images and the last two, he said.
"From the beginning of the week to the end of the week, the high polarization moves a bit," Broderick said.
"That’s interesting — we don’t have a lot to say about it other than that’s interesting."
The image researchers captured is not of the black hole closest to Earth, however, but of one at the centre of neighbouring galaxy Messier 87 that was easier to observe by telescope. It is about six billion times the mass of our sun and located about 53 million light years from Earth. One light-year is equal to 9.5 trillion kilometres.
"The newly published polarized images are key to understanding how the magnetic field allows the black hole to ‘eat’ matter and launch powerful jets,” said Andrew Chael, part of the team and a NASA Hubble Fellow at the Princeton Centre for Theoretical Science.
For Broderick, it’s not that different than building a fence.
"It’s a lot of work, a lot of sweat and frustration digging the post holes and screwing the whole thing together and making sure everything is plum, and while you’re doing that you’re focused on the mundane and onerous tasks," he said.
"But then you get to step back when you’re finished and you have a nice looking fence that’s not too crooked and you feel an immense measure of pride and that's where we are today."
This report by The Canadian Press was first published March 24, 2021.
Liam Casey, The Canadian Press
Black hole shows magnetic fields surrounding it are strong enough to resist gravity
Wits University astrophysicists are the only two scientists on African continent that contributed to the study.
IMAGE: POLARISED VIEW OF THE BLACK HOLE IN M87. THE LINES MARK THE ORIENTATION OF POLARISATION, WHICH IS RELATED TO THE MAGNETIC FIELD AROUND THE SHADOW OF THE BLACK HOLE. view more
The Event Horizon Telescope (EHT) collaboration, a multinational team of over 300 scientists including two astrophysicists from the University of the Witwatersrand (Wits University), has revealed today a new view of the massive object at the centre of the M87 galaxy: how it looks in polarised light.
This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole. The observations are key to explaining how the M87 galaxy, located 55 million light-years away, is able to launch energetic jets from its core.
"We are now seeing the next crucial piece of evidence to understand how magnetic fields behave around black holes, and how activity in this very compact region of space can drive powerful jets that extend far beyond the galaxy," says Monika Mo?cibrodzka, Coordinator of the EHT Polarimetry Working Group and Assistant Professor at Radboud Universiteit in the Netherlands.
"This work is a major milestone: the polarisation of light carries information that allows us to better understand the physics behind the image we saw in April 2019, which was not possible before," explains Iván MartÃ-Vidal, also Coordinator of the EHT Polarimetry Working Group and GenT Distinguished Researcher at the Universitat de València, Spain. He adds that "unveiling this new polarised-light image required years of work due to the complex techniques involved in obtaining and analysing the data."
Professor Roger Deane, SARAO/NRF Chair in Radio Astronomy at Wits and his postdoctoral researcher, Dr Iniyan Natarajan, are the only two scientists in the EHT collaboration that are based on the African continent. On 10 April 2019, the collaboration released the first ever image of a black hole, revealing a bright ring-like structure with a dark central region -- the black hole's shadow. Today's results reveal that a significant fraction of the light around the M87 black hole is polarised.
"When unpolarised, the oscillations of the electromagnetic fields have no preferred direction. Filters such as polarised sunglasses or magnetic fields in space, preferentially let the oscillations in one direction pass through, thereby polarising the light. Thus, the polarised-light image illuminates the structure of the magnetic fields at the edge of the black hole," says Natarajan, who was part of the EHT Polarimetry Working Group.
Black holes have long been known to launch powerful jets of energy and matter far out into space. Astronomers have relied on different physical models of how matter behaves near the black hole to better understand this process. The jet emerging from M87's core extends at least 5000 light-years from its centre, the process behind which is still unexplained.
The observations suggest that the magnetic fields at the black hole's edge are strong enough to push back on the hot gas and help it resist gravity's pull. Only the gas that slips through the field can spiral inwards to the event horizon.
To observe the heart of the M87 galaxy, the collaboration linked eight telescopes around the world to create a virtual Earth-sized telescope, the EHT. The impressive resolution obtained with the EHT is equivalent to that needed to measure the size of a cricket ball on the surface of the Moon.
This setup allowed the team to directly observe the black hole shadow and the ring of light around it, with the new polarised-light image clearly showing that the ring is magnetised. The results are published today in two separate papers in The Astrophysical Journal Letters by the EHT collaboration.
"Peering as close as we can to the edge of black holes using cutting-edge techniques is precisely the sort of challenge we relish here at Wits," says Deane, Founding Director of the newly approved Wits Centre for Astrophysics. "We are in a golden era for radio astronomy, and our involvement in projects like the Event Horizon Telescope and the Square Kilometre Array is at the centre of our plan to carry out fundamental research, and train world-class postgraduate students who will become the leading African scientists of tomorrow."
Natarajan was involved in simulating the black hole polarisation observations and was also part of the efforts to calibrate and generate the polarised image. Deane and Natarajan have also written one of the software packages that is being used to simulate black hole observations within the EHT collaboration.
"Our collaboration developed new techniques for analysing the polarisation data, which were validated on simulations before being applied to real observations," says Natarajan.
"Such challenging projects provide the opportunity to develop techniques which later find wider applicability in the community in ways which can pleasantly surprise us."
CAPTION
Group picture of the workshop which triggered the imaging the magnetic fields at the Max-Planck-Institut für Radioastronomie in Bonn, Germany, on July 15-19, 2019.
Previously thought to be science fiction, a planet in a triple-star system has been discovered
Samantha Lawler, Assistant professor of astronomy, University of Regina
A planet in a triple-star system has been discovered.(Shutterstock)
KOI-5Ab is a newly discovered planet in a triple-star system. It is a great example of the kind of astonishing discoveries that result from co-operation between large teams of astronomers using different types of telescopes and observation techniques.
There is a stereotype that “lone genius” scientists make discoveries without any help from others. This is propagated by the prestigious Nobel Prize, which is awarded to at most two or three scientists at a time.
But major discoveries, particularly in the fields of astronomy and physics, are increasingly achieved by teams of dozens or even hundreds of scientists combining data from multiple experiments and observation techniques.
How to find an exoplanet
One of the fastest-growing areas of astronomy research is the study of planets in other solar systems, called exoplanets. As of this writing, 4,367 exoplanets have been discovered. Trying to observe an exoplanet orbiting around a distant star is a bit like trying to see a firefly crawling on a searchlight, so the vast majority of exoplanets have been discovered using a variety of clever indirect techniques.
One of these is the radial velocity technique, which has been used to discover 833 exoplanets so far. This technique measures tiny shifts in the colour of light from the star as it is gently tugged by its orbiting exoplanet.
Radial velocity was first, but now more than three-quarters of the known exoplanets have been discovered using the transit technique. This technique works by measuring a star’s brightness over time, watching for regularly repeated drops in brightness, which could be caused by a planet passing in front of a star during its orbit.
The downside to the simple transit technique is that there are other astrophysical effects that can cause the same periodic drop in brightness, like background stars that vary in brightness, or starspots (like sunspots). Because of this, when interesting signals are first discovered by transit surveys, they are dispassionately numbered as “objects of interest” until they are validated as real exoplanets by another exoplanet detection technique, often radial velocity.
Right now, the TESS mission has more than two thousand objects of interest and over 100 confirmed exoplanets. The validation process is where many of the really surprising, fascinating exoplanetary systems are teased apart by impressive feats of scientific collaboration and cooperation, and the TESS and Kepler teams maintain a coordination centre to plan and share follow-up data.
All of these discoveries required a lot of additional modelling and data collection in order to understand the systems, but one of the most complicated exoplanet systems yet was announced in January 2020.
Kepler Object of Interest 5 (KOI-5) was one of the first batch of possible exoplanets sent down by the Kepler space telescope in 2009. But the first follow-up data quickly showed the system was complicated by an additional star and weird follow-up observations. Mission astronomers were gleefully (and perhaps slightly frantically) wading through possible exoplanet discoveries, so it was put aside and the data was left in the public archive. The same system was flagged again a decade later by TESS as a TESS Object of Interest (TOI-1241).
High-resolution imaging by one team of astronomers was combined with longer time baseline radial velocity data from another team and the story began to emerge: KOI-5 was a triple-star system with an exoplanet orbiting one of the stars. This discovery was presented at the January 2021 American Astronomical Society meeting, and a peer-reviewed paper is forthcoming.
I have been a user of various public data archives for exoplanet systems in my research and work, and I fully appreciate how open data policies maximize the scientific research output that can be accomplished with each dataset.
an illustration showing the triple-star system
Complex orbits
Two sun-sized stars, designated A and B, orbit each other every 29 years in the middle of the system, while a third, smaller star orbits the two central stars every 400 years. The discovered planet is called KOI-5Ab, because it orbits star A, on an orbit that is tilted wildly away from the plane of the stars’ orbits.
Data from Kepler and TESS, which required the effort of dozens of astronomers working together, has revealed the size of KOI-5Ab: seven times the radius of the Earth. Another team of astronomers used radial velocity data to measure the mass of KOI-5Ab: 57 times the mass of the Earth. Combining these numbers gives the density, and tells us this planet is a gas giant planet, a bit smaller and denser than Saturn.
As someone who became an astronomer because I’ve always loved reading science fiction stories, I like thinking about what it would be like to visit an exoplanet like this. Being a gas planet, we couldn’t actually stand on the surface, but if we could hover on the edge of its atmosphere with our spaceship, what would we see?
A few exoplanets have been measured to be very dark, so imagine looking down to see dark brown and grey clouds swirling in turbulent stripes driven by ferocious winds. In the sky, you would see one sun, 17 times larger than our sun. There would also be another much smaller sun, only half a per cent as bright as our sun (which would still be a thousand times brighter than the Earth’s full moon). This smaller sun would complete an orbit through the constellations in the sky every thirty years. The third star in the system would move much more slowly relative to the background stars, and despite its large distance, would still appear much brighter than the full moon in our sky.
Even in orbit over this planet, full darkness would only be available for brief snatches every couple hundred years when all three stars wandered into the same portion of the celestial sphere. This exoplanet system sounds like a science fiction story, but astronomers have been able to conclusively prove its existence.
Collaborative discovery
Astronomy is one of the better sciences for sharing data. We have the arXiv repository of freely accessible peer-reviewed papers, and standard practice is for telescope data to be publicly accessible in variousdatabases after a short (usually one year) proprietary period.
The co-operation between astronomers using many different observation techniques has led to incredible discoveries like the KOI-5Ab system, and as long as satellites do not ruin ground-based astronomy, large team efforts and collaborations between telescope facilities will continue to produce astronomical discoveries remarkable enough to surpass science fiction.
