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)
Saturday, December 10, 2022
Mental health support for farmers needs radical overhaul, say researchers
Mental health services in rural areas need urgent attention to ensure the needs of farmers are properly met, according to researchers.
Farmers facing worsening mental health problems are experiencing what researchers call a strained ‘landscape of support’ in rural areas.
An ESRC-funded study published today in Sociologia Ruralis indicates how the Covid-19 pandemic led to increased levels of stress, anxiety, depression, and suicidal feelings among the UK’s farming population. It raises concerns around what the research team calls ‘landscapes of support’, with civil society organisations fighting to support farmers alongside primary mental healthcare services which are sometimes inaccessible and inadequately suited to rural communities.
The research team conducted two surveys answered by more than 200 farmers and 93 support providers across the UK, and in addition carried out in-depth interviews with 22 supporters of mental health in farming across Great Britain.
Farmers are essential workers, but some have been shown to suffer with poor mental health as a result of being relatively isolated physically, socially, and culturally. At the time the pandemic hit the UK, farmers were already facing substantial uncertainty around transitions away from the EU’s Common Agricultural Policy.
By interviewing and surveying supporters of farming mental health, including chaplains, charities, auction mart staff and primary healthcare, the research found that mental health services are strained in rural communities and provide uneven coverage across the country. Some healthcare settings can be inaccessible and lack an understanding of farming, whilst informal spaces of social support are being eroded due to the loss of rural community. Mental health charities are struggling with funding and with the trauma of helping farmers through difficult times.
Academics are now calling on policymakers to take urgent action to help rural-proof primary mental healthcare services and better support civil society organisations which widen the safety net for farmers.
The research project was led by Cranfield University’s David Rose, Professor of Sustainable Agricultural Systems.
He said: “The Covid-19 pandemic exacerbated issues with farmers’ mental health that we already knew existed. For example, primary mental healthcare provision in parts of the UK is based on urban delivery models that do not suit rural communities. This leaves civil society organisations fighting to fill the support gap, but these organisations face their own struggles.
“This issue needs urgent attention to ensure farmers get the support they need and help civil society organisations to flourish. We want devolved governments to urgently address this and ensure support is in place for future shocks.”
Dr Caroline Nye, Research Fellow at the University of Exeter, said: “Recognition that mental health issues exist in rural communities in the UK is, by itself, not enough. Our research demonstrates that those who have been working hard on a professional level to support our farmers over the last few years face multiple challenges. Attention therefore needs to be focussed on ensuring that these bodies are supported in being both adaptable and sustainable over the long-term, for the benefit of the communities whom they serve."
Hannah Rees, a dairy farmer from Pembrokeshire in Wales, aged 26, said: “It’s great that more is being done to support those in agriculture, but I do still feel there is a long way to go.
“It’s important to reduce the stigma attached to mental health. Also, I think we need to stop taking a blanket approach that counselling is the only way to help people. Discussion groups and zoom meetings are other fantastic ways of providing support and countering loneliness.
“I believe we should see the introduction of mental health first aid training for those working in agriculture.”
Stephanie Berkeley, of the Farm Safety Foundation, said: “I welcome the findings of this study and agree that urgent action is needed to support the ongoing mental health of our farmers. They work long hours every day, through global pandemics and uncertain times, to put food on our plates - but this dedication comes at a price.
“We need immediate action at government level to improve the primary mental healthcare provision for those living and working in rural communities and we need to take the pressure off the rural support groups and charities who have been relied on to provide support for those in crisis situations.”
Co-authors on the paper were: Dr Faye Shortland (formerly University of Reading), Dr Caroline Nye (Exeter), Professor Matt Lobley (Exeter), Dr Ruth Little (formerly University of Sheffield), Dr Jilly Hall (SPSN), Dr Paul Hurley (formerly University of Reading), and Professor David Rose (Cranfield University, formerly University of Reading).
The research was funded by the Economic and Social Research Council as part of UKRI’s rapid response to COVID-19.
Flavian Obiero, a farmer from East Sussex, said: "As a Kenyan-born, black man in British agriculture, my mental health is in good nick. Despite the usual perception of prejudice from under-exposed people in the countryside, my experience in the industry has been largely positive. That said, we are still a long way off from any significant change in peoples' mentality to personnel diversity in the industry."
Eveey Hunter, an arable farmer from Hertfordshire, said: “As wonderful as our industry is, it can be a very lonely and isolating place for some. There are a lot of stressful factors which determine success or failure in businesses, most of which are out of our control – global markets, huge inflation of input costs and of course the weather. There is also unfortunately a stigma attached to talking about feelings, mainly with men, which is something that needs to be addressed.”
Kate Miles, from the DPJ Foundation, a mental health charity that supports the agricultural community in Wales, said: “Over the last two years, we have seen an increase in demand for our service. We know that farmers value speaking with someone who understands the pressure that they face, and this understanding is vital in mental health services. We see pockets of good work taking place across the country, including in rural areas. However, this needs to be consistent no matter where you are geographically.”
Trudy Herniman, an advisor for Cornish Mutual, which offers insurance to farms, businesses and people living and working in Cornwall, Devon, Somerset and Dorset, said: “The issues raised for farmers and those working in agriculture following the Covid-19 pandemic are still very much there and now even more exacerbated.
“Coming out of the pandemic we had the war between Ukraine and Russia, everyone feeling the effect on fuel and input cost rises. But farmers then experienced volatility in the weather as storms damaged buildings and electricity supplies.
“Farmers find it hard to ask for help and when they are distressed find it difficult to overcome the barriers by not being able to get a doctor’s appointment. Using my mental health first aid training, myself, and others from Farmerados (a welfare charity) go to markets and shows and bring tea and cake and a safe space to talk. We offer support or a listening ear. It is crucial in helping to reduce the anxiety and stress experienced by farmers and those in the farming community.”
IMAGE: RECOMMENDATIONS FOR COP15 ON DEEP REEF CONSERVATION. (C) NEKTON 2022.view more
CREDIT: CAN BE USED WITH CREDIT NEKTON 2022.
Scientists call for urgent conservation of deep reefs, one of the planet’s largest and least protected ecosystems
As world leaders, government negotiators, scientists and conservationists gather at the UN Biodiversity Conference, COP15, to agree to halt and reverse nature loss, an international team of marine scientists and conservationists have made an impassioned plea for the urgent conservation of deep reefs.
Their calls are based on a new study, recently published in the journal Conservation Letters, led byscientists from Nekton, the Western Indian Ocean (WIO) and the University of Oxford. This confirms for the first time that deep reef habitats, notably in the WIO, are largely unprotected despite being under threat from a multitude of stressors, including overfishing, pollution, climate change and, in the near future, seabed mining.
Their calls follow COP27 in Egypt, where many scientists, politicians and campaigners concluded that the 1.5C climate goal died, signing the death warrant on the vast majority of shallow reefs.
Deep reefs (found below 30 m) provide essential ecosystem services for climate change resilience, ocean health, and food security whilst also acting as a refugia for organisms threatened in shallow water, including commercially important species. Despite this, deep reefs are barely protected, even though they have a larger geographic footprint than their shallower counterparts. Furthermore, the scarcity of fish in shallow waters combined with modern deep sea fishing technologies is resulting in deep reefs being increasingly exploited by coastal communities who need fish for their food security.
“We strongly encourage deep reefs to be included in conservation and sustainable management action to complement global targets, notably 30% protection of the global ocean by 2030” said the study’s lead author, Dr Paris Stefanoudis, a marine biologist at the University of Oxford’s Department of Biology and a Research Scientist at Nekton. “Deep reefs are critical to a healthy marine ecosystem and face similar threats from overfishing, pollution and climate change faced by the much-imperilled shallow reef system.”
Covering over 8% of the global ocean, the Western Indian Ocean is one of the least known, least protected, and most threatened marine regions of our planet. Shallow and deep coral reefs of the WIO are marine biodiversity hotspots with high numbers of species that are found nowhere else on Earth. They are essential to the region’s 100 million people living within 100km of the coastline, including over three million people who are directly dependent on artisanal fishing for their livelihoods. The population is projected to double over the next 30 years, driving greater stressors on the ocean’s biological capacity to support lives and livelihoods.
The scientific team has co-developed a new framework for conserving deep reefs including practical recommendations and specific actions for regional policy-makers, conservationists and scientists. This has been published in the journal Conservation Letters.
The researchers urge policy makers to use the COP15 summit to agree to the following:
Highly protect 30% of ecosystems by 2030 (‘30 by 30’), and include deep reefs in this target.
Conserve deep reef ecosystems and their resources by specifically including them in fishery regulations, marine protected areas, and marine spatial planning.
Extend current management efforts on shallow reefs to include deep reefs as these ecosystems are often connected.
Invest in foundational, fundamental, and applied research on deep reef biodiversity, ecosystem functioning and provided services.
Develop national, international, transnational cross-stakeholder collaborations to survey and conserve deep reefs in national and international (High Seas) waters
“To halt and reverse nature loss, the UN Biodiversity Conference, COP15 must prioritise the conservation of unique ecosystems such as deep reefs, one of the least protected ecosystems on Earth” stated co-author Professor Lucy Woodall, Professor of Marine Biology at the University of Oxford, Nekton Principal Scientist, “We hope our recommendations and actions will be useful for decision makers in the WIO, be applied within the new Western Indian Ocean regional policy and provide the springboard for deep reefs to become protected across the global ocean”, continued Professor Woodall.
Co-author Melita Samoilys, CORDIO East Africa explains: “Our framework was jointly developed with a range of stakeholders from academia, research, management and government, and provides a list of actions across three themes: capacity, information collection, and information sharing. Given the scale of the issue, we have also identified which parties – such as funding agencies, government, Institutions or the research community - are needed to work together to realise those actions”.
“To ensure a prosperous and resilient Western Indian Ocean, it is essential that deep reefs are no longer ignored by scientists and policy makers, and they must be specifically considered in conservation and management strategies”, shared co-author Athur Tuda, Executive Director of the Western Indian Ocean Marine Science Association, WIOMSA.
A video summary of the findings and proposals is available at https://www.youtube.com/watch?v=lz1Tm2wo2JU&t=2s
Notes for Editors
The Publication
‘Stakeholder-derived recommendations and actions to support deep-reef conservation in the Western Indian Ocean’ published in Conservation Letters, co-authored by 18 scientists representing 18 different organisations including from South Africa, Tanzania, Seychelles, Kenya, Mozambique, UK and USA. https://conbio.onlinelibrary.wiley.com/doi/epdf/10.1111/conl.12924
WIO Conservation Framework: The UNEP’s Nairobi Convention provides the regional framework for governments, civil society and the private sector to strengthen the health and resilience of the Indian Ocean. At the Nairobi Convention’s COP10 in November 2021, the WIO nations unanimously agreed to co-create an ambitious new regional ocean strategy and accompanying policies to support sustainable ocean development underpinned by science-based management. ‘The Western Indian Ocean – Resilience & Prosperity Initiative’ (WIO-RPI), as it’s known includes establishing a just, equitably designed and managed connected network of ecologically and culturally representative protected areas in national and international waters, complementing global targets. Nekton and University of Oxford scientists are the technical partners supporting the implementation of the WIO-RPI.
Deep Reefs: Deep reefs include mesophotic (30-150 m), rariphotic (150-300 m), and cold-water coral reefs (>300 m) and have a great geographic
Nekton: Nekton works to accelerate the scientific exploration and conservation of the ocean for people and the planet. Nekton is an independent, not-for-profit research institute and is a UK registered charity. www.nektonmission.org
University of Oxford: Oxford University has been placed number 1 in the Times Higher Education World University Rankings for the seventh year running, and number 2 in the QS World Rankings 2022. At the heart of this success are the twin-pillars of our ground-breaking research and innovation and our distinctive educational offer. Oxford is world-famous for research and teaching excellence and home to some of the most talented people from across the globe. Our work helps the lives of millions, solving real-world problems through a huge network of partnerships and collaborations. The breadth and interdisciplinary nature of our research alongside our personalised approach to teaching sparks imaginative and inventive insights and solutions. Through its research commercialisation arm, Oxford University Innovation, Oxford is the highest university patent filer in the UK and is ranked first in the UK for university spinouts, having created more than 200 new companies since 1988. Over a third of these companies have been created in the past three years. The university is a catalyst for prosperity in Oxfordshire and the United Kingdom, contributing £15.7 billion to the UK economy in 2018/19, and supports more than 28,000 full time jobs.
Deep Reef Seychelles (c) Nekton 2022.
School of fish on deep reef in Seychelles (c) Nekton 2022.
Turtle glides over deep reef in Seychelles (c) Nekton 2022
In the vast oceans, one would assume their inhabitants can travel far and wide and, as a result, populations of a species would mix freely. But this doesn’t appear to be the case for a vital forage fish called the sand lance.
Sand lance are small schooling fish impressively rich in lipids, which makes them a fantastic and significant food source for at least 70 different species ranging from whales and sharks to seabirds, says UConn Associate Professor of Marine Sciences Hannes Baumann.
The Northern sand lance can be found from the waters off New Jersey all the way north to Greenland. Researchers, including Baumann and Ph.D. student Lucas Jones, were interested to see if sand lance constitute a massive, homogenous population, or whether there are genetically distinct groups. Their findings are published in the ICES Journal of Marine Science.
Baumann explains these are important questions to answer when considering conservation and sustainable management of the species, especially since the regions where sand lance live are warming faster than many areas of the planet due to climate change.
Sampling fish from such a broad range is no small task, but two years ago, Baumann and Jones began reaching out to other researchers to see if they had tissue samples to spare. Baumann credits the work to the international group of colleagues who contributed samples including co-authors from Canada and Greenland, and who helped sequence and analyze the data including co-authors from Cornell University.
In all, Baumann, Jones, and the team were able to sequence and analyze nearly 300 samples from a variety of locations across the sand lance’s range using a technique called low-coverage whole genome sequencing. They also sequenced the first reference genome for sand lance.
In a nutshell, Baumann says they found an area on the Scotian Shelf, off the coast of Nova Scotia, where a genetic break occurs. The researchers distinguished two distinct groups, one north and one south of the divide, with parts of the genome differing quite dramatically – namely on chromosomes 21 and 24. Without obvious physical barriers like a mountain range separating the groups, Baumann says it’s logical to ask how these differences are possible.
“That is the scientific conundrum,” says Baumann, and the answer, it appears, lies in the currents.
“When fish from the north reproduce and drift south, they are genetically less adapted to warmer southern waters, even if it’s five or six degrees warmer in the winter, they are just not surviving,” Baumann says. “These populations may be linked by the ocean currents, but the realized connectivity is basically zero.”
This finding is a first for the sand lance, but it has been shown in other species such as lobsters, cod, and scallops, and this research adds further evidence to an apparent temperature divide at the Scotian Shelf, and helps demonstrate that temperature is an important factor in survival.
“Example after example shows that the ocean is not as homogeneous a place as expected, and there are all kinds of things that prevent that constant mixing,”Baumann says. “We found another striking example of that.”
When researchers find adaptation in an environment where mixing is continuous, like in the ocean, Baumann says, the question is how it is possible that groups stay different, even though they are constantly encountering other genotypes. That is where powerful genomic methods, like the ones used in this paper, come in handy.
“Parts of the genome in many species have what we call a ‘genetic inversion,’ which means that the genes on the chromosome from one parent have a certain order and the genes on the same chromosome that come from the other parent that code for the same thing, and they’re the same area, but they’re flipped,” Baumann says.
These inversions mean recombination cannot occur; therefore, the genes are passed down through the generations and play an important role in adaptation.
“We discovered on chromosomes 21 and 24 there are whole regions that are completely different and that is like the trademark signature of what we call an inversion because there’s no recombination going on.”
Baumann says that knowing there are genetic and ecological barriers on the Scotian Shelf is important, because with climate change, this barrier may move north and while that may be good news for southern fish, it’s bad news for the fish currently there.
The researchers were also a little relieved in finding two clusters, because had there been many smaller clusters, it could make management and conservation more challenging, especially considering scenarios like the construction of offshore wind parks. Areas potentially well situated for wind turbines can also be habitats for sand lance, and construction disrupts habitats. If there were many, smaller population clusters, a single construction project could pose the risk of completely wiping out a cluster, whereas with more widely dispersed populations, though the local population may be temporarily disturbed, it will not be long before they are able to re-establish after construction is completed.
Baumann plans to focus further research on studying the genetic basis of the thermal divide.
“We want to make sure that this fish is productive and resilient, despite climate change, so we should make sure these areas where they are occurring are protected,” Bauman says. “These decisions should include experts to ensure if there’s an area that is very critical to sand lance, that any disturbance is temporary.”
It isn’t an unsolvable conflict, but it is something that we need to do, says Baumann, who also notes that it is possible that sand lance north of the thermal divide are already suffering more from warming because the region is warming faster.
“It could be that these two clusters have different vulnerabilities to climate change,” he says. “We don’t know that yet but that’s something that should be pursued.”
Invasive species of plants have a knack for settling in new settings and making big changes to an ecosystem, even leading to extinctions of native species.
Assistant Research Professor in UConn’s Institute of the EnvironmentJulissa Rojas-Sandoval explains that invasive plants are non-native species that have been introduced into new areas generally as a result of human activities, and that they are actively spreading, causing harm to the environment, the economy, and human health. Invasive plants may have significant long-term implications for the conservation of native biodiversity, but to combat the problem, we need to know which plants are invasive, where they’re from, and how they got there.
Rojas-Sandoval leads an international collaboration including researchers from all Central American countries, working together to compile the most comprehensive databases of invasive plant species in Central America. The collaboration is called FINCA: Flora Introduced and Naturalized in Central America, and their first paper was published this week in Biological Invasions.
The collaboration arose to meet a need, says Rojas-Sandoval. “While we have a good understanding of the processes and mechanisms of plant invasions in temperate regions, there is a huge gap in our knowledge about biological invasions in the tropics, and this lack of information is limiting our ability to respond to invasive plants.”
Remediation and the impact on the conservation of biodiversity is an important focus, but invasive plants also threaten the social and economic impact aspects of the region. Rojas-Sandoval points out that for places like her native Costa Rica, which relies on eco-tourism and agriculture, the impacts of not dealing with the invasive species could be significant.
It has been suggested that the huge diversity of plants in tropical regions may provide resistance to invasions, meaning that these ecosystems could be less threatened by invasive species because of the competition between so many different plants, but Rojas-Sandoval has studied this topic for the last 15 years and says the problem is greater than is widely understood.
“Across the tropics, the acceleration in the rates of introduction of non-native plants, as well as increments in the rates of habitat loss and forest degradation, are transforming tropical forests and making them more susceptible and less resistant to invasions,” she says.
Rojas-Sandoval explains that, as the juncture between North and South America, Central America is a regional hotspot of biodiversity, home to about 7% of the world’s plant and animal species. The region is also very vulnerable to climate change, she says:
“Climate models predict more extreme events for Central America, more and stronger hurricanes, droughts, and other impacts related to climate change. But we don’t know how climate change is already impacting both native and invasive plant species across this region. That information is necessary to be able to start doing something.”
Rojas-Sandoval and co-author Eduardo Chacón-Madrigal from the University of Costa Rica seized the opportunity and decided to start collecting and compiling any available information to make a comprehensive checklist necessary to address the challenges posed by invasive plants.
They also reached out to other researchers from across Central America to see if they would be interested in collaborating and the timing was fortunate, says Rojas-Sandoval.
“Due to COVID, people were stuck at home and, despite the many difficulties, we all had extra time to collaborate revising lists of species and providing crucial information for the project,” she says.
The team gathered data from herbarium collections in Central America and from collections around the world as well as references from existing botanical surveys, lists of alien species, and other literature.
“We compiled all this information into a list and then sent it to the experts in different countries so they could evaluate it. Then we did a second verification process because we wanted to be completely sure that we were dealing with species that were 100% alien to the region and to validate the occurrence and classification performed by the experts.
“We were able to identify that species from all over the world have been introduced to different countries in Central America, and more than 60% of them have been introduced for ornamental purposes. It is good that we can identify those species, so we know where to focus for later studies.”
The team also determined that invasive plants have made their way into all the major habitats in Central America, and the trend is steadily increasing. This information can now be used to generate specific recommendations for the governments or for the local authorities, to use their resources in the best ways possible to have an impact in controlling the invasive species, says Rojas-Sandoval, adding that the best remedy is prevention – alerting people to the issues before the plants even arrive.
For invasive plants that have already been established, it will take education, persistence, and resources to deal with the problem. However, another important aspect of the problem is that developing countries often don’t have the additional resources needed to fully address the situation.
“The local authorities and people in Central America and other regions in the tropics are already dealing with so many issues, including poverty, climate change, pollution, and over-exploitation of natural resources that it is even more important to optimize the use of any resources available to mitigate the impact of invasive species,” she says. “This is more bad news for many people dealing with so many problems, and it is crucial to increase awareness and support for the issue of biological invasions in the tropics.
“The sooner we start doing something, the better the results will be.”
The FINCA collaboration also includes: Eduardo Chacón-Madrigal (Universidad de Costa Rica), Lilian Ferrufino-Acosta (Universidad Nacional Autónoma de Honduras), Rodolfo Flores (Los Naturalistas, Panama), Omar López (Universidad de Panamá & Smithsonian Tropical Research Institute), AnaLu MacVean (York College), Indiana Coronado (Universidad Nacional Autónoma de Nicaragua), Pablo Galán and Dagoberto RodrÃguez (Herbario JardÃn Botánico La Laguna, El Salvador), and Yader Ruiz (Universidad de El Salvador).
IMAGE: ANDREA RAVIGNANI STUDIES THE VOCAL LEARNING OF SEAL PUPS.view more
CREDIT: CONNIE EDWARDS/KLEVE ZOO
NASHVILLE, Tenn., Dec. 9, 2022 – Humans appear to be one of the only animals capable of speech, which requires a range of skills and mental abilities. Among them, vocal learning — the ability to learn to produce new sounds — is critical for developing language. Only a handful of animals possess this trait, including humans, bats, whales, seals, and elephants.
However, simply possessing the ability to create new sounds is not enough to unlock language. Studying whether animals possess additional language-related skills can help us understand what it takes to learn speech and reveal the history of its evolution.
Andrea Ravignani of the Max Planck Institute for Psycholinguistics will discuss his work linking vocal learning with vocal plasticity and rhythmic capacity in his session, "Vocal learning, chorusing seal pups, and the evolution of rhythm." The presentation will take place Dec. 9 at 9:50 a.m. Eastern U.S. in Grand Hall A, as part of the 183rd Meeting of the Acoustical Society of America running Dec. 5-9 at the Grand Hyatt Nashville Hotel.
Ravignani and colleagues studied seal pups' vocal plasticity, or how well they can adjust their own voices to compensate for their environment. They found that seal pups can change the pitch and volume of their voices, much like humans can. The ability to change volume is common, but changing pitch, or fundamental frequency, is rare in animals.
"Seals may have this capacity due to convergent evolution: vocal plasticity may be a trait which evolved independently in multiple lineages due to similar evolutionary pressures," said Ravignani. "For the case of humans and seals, plasticity and vocal learning may be associated with either advanced breathing control or singing abilities in both species."
The team also tested the ability of seal pups to identify rhythmic sounds using recordings of other seals. They altered some of those recordings by changing tempos and adding rhythms to see how the young seals would react. Seal pups paid significantly more attention to recordings with regular rhythms and fast tempos.
"We can conclude that very young and untrained seals can discriminate between other seals' vocalization based on their rhythmic properties," said Ravignani. "Another mammal, apart from us, shows rhythm processing and vocalization learning; perhaps these two skills coevolved in both humans and seals."
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In the coming weeks, ASA's Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.
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ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are 300 to 500 word summaries of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.
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ABOUT THE ACOUSTICAL SOCIETY OF AMERICA
The Acoustical Society of America (ASA) is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world's leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.
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Astronomers report most distant known galaxies, detected and confirmed by JWST
Spectroscopic observations with JWST confirm four early galaxies dating back to less than 400 million years after the Big Bang, three of which are the most distant confirmed to date
IMAGE: THE JWST ADVANCED DEEP EXTRAGALACTIC SURVEY (JADES) FOCUSED ON THE AREA IN AND AROUND THE HUBBLE SPACE TELESCOPE’S ULTRA DEEP FIELD. USING WEBB’S NIRCAM INSTRUMENT, SCIENTISTS OBSERVED THE FIELD IN NINE DIFFERENT INFRARED WAVELENGTH RANGES. FROM THESE IMAGES (SHOWN AT LEFT), THE TEAM SEARCHED FOR FAINT GALAXIES THAT ARE VISIBLE IN THE INFRARED BUT WHOSE SPECTRA ABRUPTLY CUT OFF AT A CRITICAL WAVELENGTH KNOWN AS THE LYMAN BREAK. WEBB’S NIRSPEC INSTRUMENT THEN YIELDED A PRECISE MEASUREMENT OF EACH GALAXY’S REDSHIFT (SHOWN AT RIGHT). FOUR OF THE GALAXIES STUDIED ARE PARTICULARLY SPECIAL, AS THEY WERE REVEALED TO BE AT AN UNPRECEDENTEDLY EARLY EPOCH. THESE GALAXIES DATE BACK TO LESS THAN 400 MILLION YEARS AFTER THE BIG BANG, WHEN THE UNIVERSE WAS ONLY 2% OF ITS CURRENT AGE. IN THE BACKGROUND IMAGE BLUE REPRESENTS LIGHT AT 1.15 MICRONS (115W), GREEN IS 2.0 MICRONS (200W), AND RED IS 4.44 MICRONS (444W). IN THE CUTOUT IMAGES BLUE IS A COMBINATION OF 0.9 AND 1.15 MICRONS (090W+115W), GREEN IS 1.5 AND 2.0 MICRONS (150W+200W), AND RED IS 2.0, 2.77, AND 4.44 MICRONS (200W+277W+444W).view more
CREDIT: IMAGE: NASA, ESA, CSA, M. ZAMANI (ESA/WEBB), LEAH HUSTAK (STSCI) SCIENCE: BRANT ROBERTSON (UC SANTA CRUZ), S. TACCHELLA (CAMBRIDGE), E. CURTIS-LAKE (UOH), S. CARNIANI (SCUOLA NORMALE SUPERIORE), JADES COLLABORATION
An international team of astronomers has discovered the earliest and most distant galaxies confirmed to date using data from the James Webb Space Telescope (JWST). The telescope captured light emitted by these galaxies more than 13.4 billion years ago, which means the galaxies date back to less than 400 million years after the Big Bang, when the universe was only 2% of its current age.
Initial observations from JWST yielded several candidate galaxies at extreme distances, as had earlier observations with the Hubble Space Telescope. Now, four of these targets have been confirmed by obtaining long spectroscopic observations, which not only provide secure measurements of their distances, but also allow astronomers to characterize the physical properties of the galaxies.
“We’ve discovered galaxies at fantastically early times in the distant universe," said Brant Robertson, professor of astronomy and astrophysics at UC Santa Cruz. “With JWST, for the first time we can now find such distant galaxies and then confirm spectroscopically that they really are that far away.”
Astronomers measure the distance to a galaxy by determining its redshift. Due to the expansion of the universe, distant objects appear to be receding from us and their light is stretched to longer, redder wavelengths by the Doppler effect. Photometric techniques based on images captured through different filters can provide redshift estimates, but definitive measurements require spectroscopy, which separates the light from an object into its component wavelengths.
The new findings focus on four galaxies with redshifts higher than 10. Two galaxies initially observed by Hubble now have confirmed redshifts of 10.38 and 11.58. The two most distant galaxies, both detected in JWST images, have redshifts of 13.20 and 12.63, making them the most distant galaxies confirmed by spectroscopy to date. A redshift of 13.2 corresponds to about 13.5 billion years ago.
“These are well beyond what we could have imagined finding before JWST,” Robertson said. “At redshift 13, the universe is only about 325 million years old.”
Robertson and Emma Curtis-Lake from the University of Hertfordshire (U.K.) will be presenting the new findings on December 12 at a Space Telescope Science Institute (STScI) conference in Baltimore on “First Science Results from JWST.” They are the lead authors of two papers on the results that have not yet been through the peer-review process (see links below).
The observations result from a collaboration of scientists who led the development of two of the instruments onboard Webb, the Near-Infrared Camera (NIRCam) and the Near-Infrared Spectrograph (NIRSpec). The investigation of the faintest and earliest galaxies was the leading motivation in the concepts for these instruments. In 2015, the instrument teams joined together to propose the JWST Advanced Deep Extragalactic Survey (JADES), an ambitious program that has been allocated just over one month of the telescope’s time and is designed to provide a view of the early universe unprecedented in both depth and detail. JADES is an international collaboration of more than eighty astronomers from ten countries.
“These results are the culmination of why the NIRCam and NIRSpec teams joined together to execute this observing program,” said Marcia Rieke, NIRCam principal investigator at the University of Arizona.
The JADES program began with NIRCam, using over 10 days of mission time to observe a small patch of sky in and around the Hubble Ultra Deep Field. Astronomers have been studying this region for over 20 years with nearly all large telescopes. The JADES team observed the field in nine different infrared wavelength ranges, capturing exquisite images that reveal nearly 100,000 distant galaxies, each billions of light years away.
The team then used the NIRSpec spectrograph for a single three-day observation period to collect the light from 250 faint galaxies. This yielded precise redshift measurements and revealed the properties of the gas and stars in these galaxies.
“With these measurements, we can know the intrinsic brightness of the galaxies and figure out how many stars they have,” Robertson said. “Now we can start to really pick apart how galaxies are put together over time.”
Coauthor Sandro Tacchella from the University of Cambridge in the United Kingdom added, “It is hard to understand galaxies without understanding the initial periods of their development. Much as with humans, so much of what happens later depends on the impact of these early generations of stars. So many questions about galaxies have been waiting for the transformative opportunity of Webb, and we’re thrilled to be able to play a part in revealing this story.”
According to Robertson, star formation in these early galaxies would have begun about 100 million years earlier than the age at which they were observed, pushing the formation of the earliest stars back to around 225 million years after the Big Bang.
“We are seeing evidence of star formation about as early as we could expect based on our models of galaxy formation,” he said.
Other teams have identified candidate galaxies at even higher redshifts based on photometric analyses of JWST images, but these have yet to be confirmed by spectroscopy. JADES will continue in 2023 with a detailed study of another field, this one centered on the iconic Hubble Deep Field, and then a return to the Ultra Deep Field for another round of deep imaging and spectroscopy. Many more candidates in the field await spectroscopic investigation, with hundreds of hours of additional time already approved.
The following papers on the new findings have been submitted for publication and are available online:
IMAGE: THIS ARTIST'S ILLUSTRATION SHOWS THE LOCATION AND SIZE OF A HYPOTHETICAL CLOUD OF DUST SURROUNDING OUR SOLAR SYSTEM. ASTRONOMERS SEARCHED THROUGH 200,000 IMAGES AND MADE TENS OF THOUSANDS OF MEASUREMENTS FROM HUBBLE SPACE TELESCOPE TO DISCOVER A RESIDUAL BACKGROUND GLOW IN THE SKY. BECAUSE THE GLOW IS SO SMOOTHLY DISTRIBUTED, THE LIKELY SOURCE IS INNUMERABLE COMETS – FREE-FLYING DUSTY SNOWBALLS OF ICE. THEY FALL IN TOWARD THE SUN FROM ALL DIFFERENT DIRECTIONS, SPEWING OUT AN EXHAUST OF DUST AS THE ICES SUBLIMATE DUE TO HEAT FROM THE SUN. IF REAL, THIS WOULD BE A NEWLY DISCOVERED ARCHITECTURAL ELEMENT OF THE SOLAR SYSTEM.view more
CREDIT: NASA, ESA, AND ANDI JAMES (STSCI)
Aside from a tapestry of glittering stars, and the glow of the waxing and waning Moon, the nighttime sky looks inky black to the casual observer. But how dark is dark?
To find out, astronomers decided to sort through 200,000 images from NASA's Hubble Space Telescope and made tens of thousands of measurements on these images to look for any residual background glow in the sky, in an ambitious project called SKYSURF. This would be any leftover light after subtracting the glow from planets, stars, galaxies, and from dust in the plane of our solar system (called zodiacal light).
When researchers completed this inventory, they found an exceedingly tiny excess of light, equivalent to the steady glow of 10 fireflies spread across the entire sky. That's like turning out all the lights in a shuttered room and still finding an eerie glow coming from the walls, ceiling, and floor.
The researchers say that one possible explanation for this residual glow is that our inner solar system contains a tenuous sphere of dust from comets that are falling into the solar system from all directions, and that the glow is sunlight reflecting off this dust. If real, this dust shell could be a new addition to the known architecture of the solar system.
This idea is bolstered by the fact that in 2021 another team of astronomers used data from NASA's New Horizons spacecraft to also measure the sky background. New Horizons flew by Pluto in 2015, and a small Kuiper belt object in 2018, and is now heading into interstellar space. The New Horizons measurements were done at a distance of 4 billion to 5 billion miles from the Sun. This is well outside the realm of the planets and asteroids where there is no contamination from interplanetary dust.
New Horizons detected something a bit fainter that is apparently from a more distant source than Hubble detected. The source of the background light seen by New Horizons also remains unexplained. There are numerous theories ranging from the decay of dark matter to a huge unseen population of remote galaxies.
"If our analysis is correct there's another dust component between us and the distance where New Horizons made measurements. That means this is some kind of extra light coming from inside our solar system," said Tim Carleton, of Arizona State University (ASU).
"Because our measurement of residual light is higher than New Horizons we think it is a local phenomenon that is not from far outside the solar system. It may be a new element to the contents of the solar system that has been hypothesized but not quantitatively measured until now," said Carleton.
Hubble veteran astronomer Rogier Windhorst, also of ASU, first got the idea to assemble Hubble data to go looking for any "ghost light." "More than 95% of the photons in the images from Hubble's archive come from distances less than 3 billion miles from Earth. Since Hubble's very early days, most Hubble users have discarded these sky-photons, as they are interested in the faint discrete objects in Hubble's images such as stars and galaxies," said Windhorst. "But these sky-photons contain important information which can be extracted thanks to Hubble's unique ability to measure faint brightness levels to high precision over its three decades of lifetime."
A number of graduate and undergraduate students contributed to project SKYSURF, including Rosalia O'Brien, Delondrae Carter and Darby Kramer at ASU, Scott Tompkins at the University of Western Australia, Sarah Caddy at Macquarie University in Australia, and many others.
The Hubble Space Telescope is a project of international cooperation between NASA and ESA. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble and Webb science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, in Washington, D.C.
SKYSURF: Constraints on Zodiacal Light and Extragalactic Background Light through Panchromatic HST All-sky Surface-brightness Measurements: II. First Limits on Diffuse Light at 1.25, 1.4, and 1.6 μm
