Hen harrier row could unlock other conservation conflicts

Peer-Reviewed Publication

UNIVERSITY OF EXETER

 

IMAGE: ADULT FEMALE HEN HARRIER view more 

CREDIT: JOHN WRIGHT

The long-running row over Britain’s hen harriers could offer lessons for other conservation conflicts, new research shows.

Hen harriers’ prey includes birds that are shot for sport, especially red grouse, leading to conflict between shooting organisations and birds-of-prey conservation groups.

The new study, by the University of Exeter, analyses almost three decades of UK newspaper articles to see how the debate has evolved.

It finds a peak of “polarisation” after the launch in 2016 of a government-backed action plan for the recovery of hen harrier populations.

“Our research offers a variety of options that could help with other conservation conflicts,” said Filippo Marino, of the Centre for Ecology and Conservation on Exeter’s Penryn campus in Cornwall.

“We identified the most polarising issues in the debate, and other areas where there was broad agreement. It’s useful for opponents to be aware that they share some common ground, and to understand their key areas of disagreement.

“Our findings also show that the hen harriers debate has been dominated by a few high-profile people and organisations. This has probably perpetuated the conflict, increased polarisation and hindered resolutions.”

“Allowing new voices to speak might change the dynamics and help unlock this entrenched debate.”

Researchers examined 737 statements in 131 newspaper articles published from August 1993 to December 2019, finding three main themes in the debate: problems, solutions and reactions.

They found that a multitude of people and organisations contributed to the hen harrier debate. However, only a subset was regularly quoted.

“Despite a long history of conservation measures and the recent decline of territorial pairs of harriers in Great Britain, the hen harrier conflict appears to have worsened and become more polarised both in England and Scotland,” Marino said.

“A key point of conflict is a relocation scheme, known as brood management, that moves hen harriers away from grouse moors. Meanwhile, reintroduction of hen harriers in southern England – where numbers are lower compared to northern England and Scotland – have been less polarising.”

The research was funded by the University of Exeter in partnership with Natural England.

The paper, published in the journal People and Nature, is entitled: “Stakeholder discourse coalitions and polarisation in the hen harrier conservation debate in news media.”

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JOURNAL

People and Nature

DOI

10.1002/pan3.10437 

METHOD OF RESEARCH

Data/statistical analysis

ARTICLE TITLE

Stakeholder discourse coalitions and polarisation in the hen harrier conservation debate in news media

ARTICLE PUBLICATION DATE

14-Feb-2023

Whale warning as clock ticks towards deep-sea mining

Peer-Reviewed Publication

UNIVERSITY OF EXETER

 

IMAGE: A VIEW OF THE NORMAND ENERGY DEPLOYING THE PATANIA II NODULE COLLECTOR VISIBLE (GREEN), SEEN FROM THE RAINBOW WARRIOR. THE VESSEL IS CHARTERED BY GLOBAL SEA MINERAL RESOURCES (GSR), A BELGIAN COMPANY RESEARCHING DEEP SEA MINING IN THE PACIFIC. THE COMPANY IS CURRENTLY TESTING MINING GEAR WITH THE AIM OF FUTURE COMMERCIAL EXTRACTION OF MINERALS FROM THE SEABED. view more 

CREDIT: MARTEN VAN DIJL / GREENPEACE

Seabed mining could soon begin in the deep ocean – but the potential impact on animals including whales is unknown, researchers have warned.

Commercial-scale deep seabed mining in international waters could be permitted for the first time later this year.

In a new paper, scientists from the University of Exeter and Greenpeace Research Laboratories say that deep seabed mining could be a “significant risk to ocean ecosystems”, with “long lasting and irreversible” effects.

The study focuses on cetaceans (mammals such as whales, dolphins and porpoises) and says urgent research is needed to assess potential impacts.

“Like many animals, cetaceans are already facing multiple stressors including climate change,” said Dr Kirsten Thompson, of the University of Exeter.

“Very little research has examined the impact that deep-sea minerals extraction would have on cetaceans.

“Cetaceans are highly sensitive to sound, so noise from mining is a particular concern.”

The sounds expected  to be produced by mining operations, including from remotely operated vehicles on the seafloor, are likely to overlap with the frequencies at which cetaceans communicate, the researchers stress.

“We searched for data on how much noise such mining would cause, but no published assessment is available,” Dr Thompson added.

“We know noise pollution in the ocean is already a problem for cetaceans and introducing another industry that is expected to operate 24/7 would inevitably add to existing anthropogenic noise were deep seabed mining to go ahead.

“Despite this lack of information, it appears industrial-scale mining could soon begin in one of the planet’s few remaining undisturbed environments.”

The Clarion-Clipperton Zone (CCZ) in the Pacific Ocean, which provides habitat for about 25 cetacean species, including dolphins and sperm whales, is of particular interest to mining companies aiming to exploit polymetallic nodules.

In addition, mining companies are also looking to target seabed mineral resources in areas around seamounts and deep sea hydrothermal vents.

“Seamounts are now known as important offshore habitats for some cetacean populations that forage or regroup around them but we still lack basic knowledge of these fragile ecosystems,” said Dr Solène Derville, of Oregon State University.

“In this context, it is very hard to assess the magnitude of the impacts of seamount seabed mining on the animals that live and feed around these structures.”

Two-year rule

No commercial-scale seabed mining has yet occurred outside the exclusive economic zones (EEZs) of coastal nations, although 31 exploration permits have been issued for areas beyond national jurisdiction by the International Seabed Authority, a United Nations body.

However, in June 2021, the Pacific island of Nauru triggered the so-called "two-year rule" and informed the International Seabed Authority (ISA) that it plans to mine the deep sea – meaning that mining could go ahead in June this year with whatever regulations the ISA has formulated by that time.

Nauru is working with a Canadian firm called The Metals Company, which has already begun testing mining equipment in Pacific waters.

“Commercial-scale mining is expected to operate 24-hours a day, with multiple operations extracting minerals across an area of the seabed,” Dr Thompson said.

“We don’t know how this will affect cetaceans or the vast range of other marine species.

“What we do know is that it will be difficult to stop seabed mining once it has started.

“Given the imminent threat that the two-year rule presents to ocean conservation, we suggest there is no time to waste.”

The paper, published in the journal Frontiers in Marine Science, is titled: Urgent assessment needed to evaluate potential impacts on cetaceans from deep seabed mining.

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JOURNAL

Frontiers in Marine Science

DOI

10.3389/fmars.2023.1095930 

METHOD OF RESEARCH

Commentary/editorial

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Urgent assessment needed to evaluate potential impacts on cetaceans from deep seabed mining

ARTICLE PUBLICATION DATE

14-Feb-2023

How to make hydrogen straight from seawater – no desalination required

Peer-Reviewed Publication

RMIT UNIVERSITY

 

IMAGE: THE NEW METHOD FROM RMIT UNIVERSITY RESEARCHERS SPLITS SEAWATER DIRECTLY INTO HYDROGEN AND OXYGEN – SKIPPING THE NEED FOR DESALINATION AND ITS ASSOCIATED COST, ENERGY CONSUMPTION AND CARBON EMISSIONS. view more 

CREDIT: RMIT UNIVERSITY

Researchers have developed a cheaper and more energy-efficient way to make hydrogen directly from seawater, in a critical step towards a truly viable green hydrogen industry.

The new method from RMIT University researchers splits the seawater directly into hydrogen and oxygen – skipping the need for desalination and its associated cost, energy consumption and carbon emissions.

Hydrogen has long been touted as a clean future fuel and a potential solution to critical energy challenges, especially for industries that are harder to decarbonise like manufacturing, aviation and shipping.

Almost all the world’s hydrogen currently comes from fossil fuels and its production is responsible for around 830 million tonnes of carbon dioxide a year*, equivalent to the annual emissions of the United Kingdom and Indonesia combined. 

But emissions-free ‘green’ hydrogen, made by splitting water, is so expensive that it is largely commercially unviable and accounts for just 1% of total hydrogen production globally.

Lead researcher Dr Nasir Mahmood, a Vice-Chancellor’s Senior Research Fellow at RMIT, said green hydrogen production processes were both costly and relied on fresh or desalinated water.

“We know hydrogen has immense potential as a clean energy source, particularly for the many industries that can’t easily switch over to be powered by renewables,” Mahmood said.

“But to be truly sustainable, the hydrogen we use must be 100% carbon-free across the entire production life cycle and must not cut into the world’s precious freshwater reserves.

“Our method to produce hydrogen straight from seawater is simple, scaleable and far more cost-effective than any green hydrogen approach currently in the market.

“With further development, we hope this could advance the establishment of a thriving green hydrogen industry in Australia.”   

A provisional patent application has been filed for the new method, detailed in a lab-scale study published in Wiley journal, Small.

Splitting the difference: a catalyst for seawater

To make green hydrogen, an electrolyser is used to send an electric current through water to split it into its component elements of hydrogen and oxygen.

These electrolysers currently use expensive catalysts and consume a lot of energy and water – it can take about nine litres to make one kilogram of hydrogen. They also have a toxic output: not carbon dioxide, but chlorine.

“The biggest hurdle with using seawater is the chlorine, which can be produced as a by-product. If we were to meet the world’s hydrogen needs without solving this issue first, we’d produce 240 million tons per year of chlorine each year – which is three to four times what the world needs in chlorine. There’s no point replacing hydrogen made by fossil fuels with hydrogen production that could be damaging our environment in a different way,” Mahmood said.

“Our process not only omits carbon dioxide, but also has no chlorine production.”

The new approach devised by a team in the multidisciplinary Materials for Clean Energy and Environment (MC2E) research group at RMIT uses a special type of catalyst developed to work specifically with seawater.

The study, with PhD candidate Suraj Loomba, focused on producing highly efficient, stable catalysts that can be manufactured cost-effectively.

“These new catalysts take very little energy to run and could be used at room temperature,” Mahmood said.

“While other experimental catalysts have been developed for seawater splitting, they are complex and hard to scale.

“Our approach focused on changing the internal chemistry of the catalysts through a simple method, which makes them relatively easy to produce at large-scale so they can be readily synthesised at industrial scales," Loomba said.

Mahmood said the technology had promise to significantly bring down the cost of electrolysers - enough to meet the Australian Government's goal for green hydrogen production of $2/kilogram, to make it competitive with fossil fuel-sourced hydrogen.

The researchers at RMIT are working with industry partners to develop aspects of this technology.

The next stage in the research is the development of a prototype electrolyser that combines a series of catalysts to produce large quantities of hydrogen.

‘Nitrogen-doped Porous Nickel Molybdenum Phosphide Sheets for Efficient Seawater Splitting’, co-authored by Suraj Loomba, Muhammad Waqas Khan, Muhammad Haris, Seyed Mahdi Mousavi, Nasir Mahmood, et al., is published in Small (DOI: 10.1002/smll.202207310).

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JOURNAL

Small

DOI

10.1002/smll.202207310 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Nitrogen-doped Porous Nickel Molybdenum Phosphide Sheets for Efficient Seawater Splitting

Oldest spinosaur brains revealed

Peer-Reviewed Publication

UNIVERSITY OF SOUTHAMPTON

 

IMAGE: ARTIST'S IMPRESSION OF CERATOSUCHOPS AND THE ORIENTATION OF THE ENDOCAST IN THE SKULL. view more 

CREDIT: ANTHONY HUTCHINGS

Researchers from the University of Southampton and Ohio University have reconstructed the brains and inner ears of two British spinosaurs, helping uncover how these large predatory dinosaurs interacted with their environment. 

Spinosaurs are an unusual group of theropod dinosaurs, equipped with long, crocodile-like jaws and conical teeth. These adaptations helped them live a somewhat-aquatic lifestyle that involved stalking riverbanks in quest of prey, among which were large fish. This way of life was very different from that of more familiar theropods, like Allosaurus and Tyrannosaurus.

To better understand the evolution of spinosaur brains and senses, the team scanned fossils of Baryonyx from Surrey and Ceratosuchops from the Isle of Wight. These two are the oldest spinosaurs for which braincase material is known. The huge creatures would have been roaming the planet about 125 million years ago years ago. The braincases of both specimens are well preserved, and the team digitally reconstructed the internal soft tissues that had long rotted away.

The researchers found the olfactory bulbs, which process smells, weren’t particularly developed, and the ear was probably attuned to low frequency sounds. Those parts of the brain involved in keeping the head stable and the gaze fixed on prey were possibly less developed than they were in later, more specialised spinosaurs.

Findings are due to be published in the Journal of Anatomy.

“Despite their unusual ecology, it seems the brains and senses of these early spinosaurs retained many aspects in common with other large-bodied theropods – there is no evidence that their semi-aquatic lifestyles are reflected in the way their brains are organised,” said University of Southampton PhD student Chris Barker, who led the study.

One interpretation of this evidence is that the theropod ancestors of spinosaurs already possessed brains and sensory adaptations suited for part-time fish catching, and that ‘all’ spinosaurs needed to do to become specialised for a semi-aquatic existence was evolve an unusual snout and teeth.

“Because the skulls of all spinosaurs are so specialised for fish-catching, it’s surprising to see such ‘non-specialised’ brains,” said contributing author Dr Darren Naish. “But the results are still significant. It’s exciting to get so much information on sensory abilities – on hearing, sense of smell, balance and so on – from British dinosaurs. Using cutting-edged technology, we basically obtained all the brain-related information we possibly could from these fossils,” Dr Naish said.

Over the last few years, the EvoPalaeo Lab at the University of Southampton has conducted substantial research on new spinosaurs from the Isle of Wight. Ceratosuchops itself was only announced by the team in 2021, and its discovery was followed up by the publication of another new spinosaur – the gigantic White Rock spinosaur – in 2022. The braincase of Ceratosuchops was scanned at the μ-Vis X-ray Imaging Centre at the University of Southampton, home to some of the most powerful CT scanners in the country, and a model of its brain will be on display alongside its bones at Dinosaur Isle Museum in Sandown, on the Isle of Wight.

“This new research is just the latest in what amounts to a revolution in palaeontology due to advances in CT-based imaging of fossils,” said co-author Lawrence M. Witmer, professor of anatomy at the Ohio University Heritage College of Osteopathic Medicine, who has been CT scanning dinosaurs—including Baryonyx—for over 25 years. "We’re now in a position to be able to assess the cognitive and sensory capabilities of extinct animals and explore how the brain evolved in behaviourally extreme dinosaurs like spinosaurs.”

“This new study highlights the significant role British fossils have in our constantly evolving, fast-moving understanding of dinosaurs, and shows how the UK – and the University of Southampton in particular – is at the forefront of spinosaur research,” said Dr Neil Gostling who leads the University of Southampton’s EvoPalaeoLab. “Spinosaurs themselves are one of the most controversial of all dinosaur groups, and this study is a valuable addition to ongoing discussions of their biology and evolution.”

Three-dimensional reconstruction of the brain cavity and associated nerves and blood vessels within the braincase of the iconic british spinosaurid Baryonyx walkeri.

CREDIT

WitmerLab/Chris_Barker

Three-dimensional reconstruction of the brain cavity (purple), cranial nerves (yellow), inner ear (pink) and blood vessels (red and blue) of the British spinosaurid Ceratosuchops inferodios. This predator likely had an unexceptional sense of smell and could hear low frequency sounds.

CREDIT

Chris Barker

Notes to Editors

1. For images, an artist’s impression, moving footage and related captions and credits, please visit and download from: https://bit.ly/3DVxl9a
    
2. A video about the research in this press release can be found and embedded from here: https://www.youtube.com/watch?v=Mf2OpItIXHo
    
3. The paper ‘Modified skulls but conservative brains? The palaeoneurology and endocranial anatomy of baryonychine dinosaurs (Theropoda: Spinosauridae)’ will be published in Journal Of Anatomy DOI: 10.1111/joa.13837 after the embargo has lifted.
   
   To see a copy of the paper in advance, please email press@soton.ac.uk
    
4. For interviews with Chris Barker or Dr Neil Gostling, please contact Peter Franklin, Media Relations, University of Southampton press@soton.ac.uk +44 23 8059 3212
    
5. To contact Professor Lawrence M. Witmer in Ohio email: witmerl@ohio.edu
    
6. For more about Biological Sciences at the University of Southampton visit: https://www.southampton.ac.uk/about/faculties-schools-departments/school-of-biological-sciences
    
7. The University of Southampton drives original thinking, turns knowledge into action and impact, and creates solutions to the world’s challenges. We are among the top 100 institutions globally (QS World University Rankings 2023). Our academics are leaders in their fields, forging links with high-profile international businesses and organisations, and inspiring a 22,000-strong community of exceptional students, from over 135 countries worldwide. Through our high-quality education, the University helps students on a journey of discovery to realise their potential and join our global network of over 200,000 alumni. www.southampton.ac.uk
    
8. For more on Ohio University visit: https://www.ohio.edu/
    
9. More about the μ-Vis X-ray Imaging Centre at the University of Southampton can be found at: https://www.southampton.ac.uk/muvis/index.page

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JOURNAL

Journal of Anatomy

DOI

10.1111/joa.13837 

METHOD OF RESEARCH

Imaging analysis

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Modified skulls but conservative brains? The palaeoneurology and endocranial anatomy of baryonychine dinosaurs (Theropoda: Spinosauridae)

ARTICLE PUBLICATION DATE

13-Feb-2023

Brain changes in fighter pilots may cast light on astronauts during space travel

Study is the first to investigate functional brain connectivity in fighter pilots, finding specific changes that may reveal the effects of space travel

Peer-Reviewed Publication

FRONTIERS

One cannot explore the profound mysteries of space without being changed by it. This is the message underlying a new study in Frontiers in Physiology.

The study examined the brains of F16 fighter pilots, which have a lot in common with those of astronauts in terms of adapting to altered gravity levels and rapidly processing conflicting sensory information. MRI scans revealed that pilots with more flight experience showed specific brain connectivity patterns in areas related to processing sensorimotor information. They also showed differences in brain connectivity compared with non-pilots. The study will help us to understand the effects of space flight on the brain and may aid in providing better training programs for pilots or astronauts.      

Spaceships: a rollercoaster for the brain

Blasting off into space places significant demands on the body and mind. These include altered levels of gravity, from the g-forces present during blast-off to the low-gravity environment in space. Other issues include rapidly interpreting sensory and visual stimuli that are sometimes conflicting, while controlling a complex vehicle at extreme speeds.

These factors are a potent cocktail, and previous research has suggested that the brain may undergo structural and functional changes after space flight and astronaut training, in a process called neural plasticity. Understanding these changes could help us to better prepare astronauts for long journeys, which is crucial if we are ever to reach other planets.

A pilot study

Given that astronauts are a rare commodity, the researchers behind the current study hypothesized that studying the brain in members of a somewhat similar profession may provide the answers they need. “Fighter pilots have some interesting similarities with astronauts, such as exposure to altered g-levels, and the need to interpret visual information and information coming from head movements and acceleration (vestibular information),” said Prof Floris Wuyts of the University of Antwerp, senior author on the study. “By establishing the specific brain connectivity characteristics of fighter pilots, we can gain more insight into the condition of astronauts after spaceflight.”

To investigate this, the researchers recruited 10 fighter jet pilots from the Belgian Air Force, alongside a control group of 10 non-pilots, and performed MRI scans of their brains to establish the first ever study of functional brain connectivity in fighter pilots.    

Adapting to extreme demands

Interestingly, the researchers found differences in brain connectivity between experienced and less experienced pilots, suggesting that brain changes occur with an increased number of flight hours. These differences included less connectivity in certain areas of the brain processing sensorimotor information, which may indicate the brain adapting to cope with the extreme conditions experienced during flight.

Experienced pilots also demonstrated increased connectivity in frontal areas of the brain that are likely involved in the cognitive demands of flying a complicated jet. When comparing pilots and non-pilots, the researchers found that areas of the brain processing vestibular and visual information were more connected in pilots. This may reflect the requirements for pilots to cope with processing multiple and occasionally conflicting visual and vestibular stimuli at once and to prioritize the most important stimuli, such as reading cockpit instruments.   

“By demonstrating that vestibular and visual information is processed differently in pilots compared to non-pilots, we can recommend that pilots are a suitable study group to gain more insight into the brain’s adaptations toward unusual gravitational environments, such as during spaceflight,” said Dr Wilhelmina Radstake, first author on the study who conducted a Master’s thesis on this topic in Prof Wuyt’s lab.

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JOURNAL

Frontiers in Physiology

DOI

10.3389/fphys.2023.1082166 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Neuroplasticity in F16 fighter jet pilots

ARTICLE PUBLICATION DATE

15-Feb-2023

NASA’s IMAP spacecraft completes mission critical design review, moves closer to 2025 launch

SwRI leads payload management of mission to study the boundary of the solar system

Business Announcement

SOUTHWEST RESEARCH INSTITUTE

 

IMAGE: NASA’S INTERSTELLAR MAPPING AND ACCELERATION PROBE (IMAP) SPACECRAFT HAS COMPLETED A CRITICAL DESIGN REVIEW AND IS ON TRACK FOR ITS SCHEDULED 2025 LAUNCH. SOUTHWEST RESEARCH INSTITUTE IS MANAGING THE PAYLOAD OFFICE, PROVIDING A SCIENTIFIC INSTRUMENT AS WELL AS CONTRIBUTING OTHER TECHNOLOGY FOR THE MISSION. view more 

CREDIT: NASA/JOHNS HOPKINS APL/PRINCETON UNIVERSITY

SAN ANTONIO — Feb. 14, 2023 —NASA’s Interstellar Mapping and Acceleration Probe (IMAP) spacecraft has completed the Mission Critical Design Review and is on track to meet its scheduled 2025 launch. Southwest Research Institute (SwRI) is managing the payload office, providing the scientific instrument Compact Dual Ion Composition Experiment (CoDICE) and is participating on other instrument teams for the mission, which will study the interaction between the solar wind and the interstellar medium as well as the fundamental processes of particle acceleration in space.

“IMAP will help us gain a greater understanding of how our Sun interacts with the rest of the solar system,” said Susan Pope, director of SwRI’s Department of Space Instrumentation and IMAP’s payload manager. “IMAP will give us a more complete picture of the interaction between the interstellar medium and the solar wind, providing a better understanding of our place in the universe.”

IMAP is designed to help researchers better understand the boundary of the heliosphere, the magnetic bubble created by the solar wind, the constant flow of particles from the Sun. The bubble surrounds and protects our solar system, limiting the amount of harmful cosmic radiation entering the heliosphere. IMAP instruments will collect and analyze particles that make it through the barrier.

Additionally, the mission will examine the fundamental processes that accelerate particles throughout the heliosphere and beyond. The resulting energetic particles and cosmic rays can harm astronauts and space-based technologies.

The Institute is providing the CoDICE instrument, which combines the capabilities of multiple instruments into one patented sensor. Initially developed through SwRI internal funding, CoDICE will measure the distribution and composition of interstellar pickup ions, particles that make it through the “heliospheric” filter. It will also characterize solar wind ions as well as the mass and composition of highly energized solar particles associated with flares and coronal mass ejections.

SwRI is a key member of the teams for the IMAP-Hi and IMAP-Lo instruments, responsible for the detector on the IMAP-Hi and the conversion subsystem on the IMAP-Lo. SwRI is also building high-voltage power supplies for the Solar Wind Electron (SWE) instrument, which measures the distribution of thermal electrons in the solar wind, and the Global Solar Wind Structure (GLOWS) instrument, a non-imaging photometer that will observe the structure of the solar wind. Additionally, SwRI is providing digital electronics for four IMAP instruments.

“Most of the instruments have completed their engineering model testing and have started fabricating their flight hardware,” Pope said. “All instruments are scheduled to be delivered to the Johns Hopkins University Applied Physics Laboratory for installation on the spacecraft between December 2023 and February 2024.”

Princeton University professor David J. McComas leads the mission with an international team of 24 partner institutions. The Johns Hopkins Applied Physics Laboratory in Laurel, Maryland builds the spacecraft and operates the mission. IMAP is the fifth mission in NASA’s Solar Terrestrial Probes (STP) Program portfolio. The Explorers and Heliophysics Project Division at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the STP Program for the agency’s Heliophysics Division of NASA’s Science Mission Directorate.

For more information, visit https://www.swri.org/planetary-science.

Four classes of planetary systems

Peer-Reviewed Publication

UNIVERSITY OF BERN

 

IMAGE: ARTIST IMPRESSION OF THE FOUR CLASSES OF PLANETARY SYSTEM ARCHITECTURE. A NEW ARCHITECTURE FRAMEWORK ALLOWS RESEARCHERS TO STUDY AN ENTIRE PLANETARY SYSTEM AT THE SYSTEMS LEVEL. IF THE SMALL PLANETS WITHIN A SYSTEM ARE CLOSE TO THE STAR AND MASSIVE PLANETS FURTHER AWAY, SUCH SYSTEMS HAVE ‘ORDERED’ ARCHITECTURE. CONVERSELY, IF THE MASS OF THE PLANETS IN A SYSTEM TENDS TO DECREASE WITH DISTANCE TO THE STAR THESE SYSTEMS ARE ‘ANTI-ORDERED’. IF ALL PLANETS IN A SYSTEM HAVE SIMILAR MASSES, THEN THE ARCHITECTURE OF THIS SYSTEM IS ‘SIMILAR’. ‘MIXED’ PLANETARY SYSTEMS ARE THOSE IN WHICH THE PLANETARY MASSES SHOW LARGE VARIATIONS. RESEARCH SUGGESTS THAT PLANETARY SYSTEMS WHICH HAVE THE SAME ARCHITECTURE CLASS HAVE COMMON FORMATION PATHWAYS. view more 

CREDIT: © NCCR PLANETS, ILLUSTRATION: TOBIAS STIERLI

In our solar system, everything seems to be in order: The smaller rocky planets, such as Venus, Earth or Mars, orbit relatively close to our star. The large gas and ice giants, such as Jupiter, Saturn or Neptune, on the other hand, move in wide orbits around the sun. In two studies published in the scientific journal Astronomy & Astrophysics, researchers from the Universities of Bern and Geneva and the National Centre of Competence in Research (NCCR) PlanetS show that our planetary system is quite unique in this respect.

Like peas in a pod

"More than a decade ago, astronomers noticed, based on observations with the then groundbreaking Kepler telescope, that planets in other systems usually resemble their respective neighbours in size and mass – like peas in a pod," says study lead author Lokesh Mishra, researcher at the University of Bern and Geneva, as well as the NCCR PlanetS. But for a long time it was unclear whether this finding was due to limitations of observational methods. "It was not possible to determine whether the planets in any individual system were similar enough to fall into the class of the ‘peas in a pod’ systems, or whether they were rather different – just like in our solar system," says Mishra.

Therefore, the researcher developed a framework to determine the differences and similarities between planets of the same systems. And in doing so, he discovered that there are not two, but four such system architectures.

Four classes of planetary systems

"We call these four classes 'similar', 'ordered', 'anti-ordered' and 'mixed'," says Mishra. Planetary systems in which the masses of neighbouring planets are similar to each other, have similar architecture. Ordered planetary systems are those, in which the mass of the planets tends to increase with distance from the star – just as in our solar system. If, on the other hand, the mass of the planets roughly decreases with distance from the star, researchers speak of an anti-ordered architecture of the system. And mixed architectures occur, when the planetary masses in a system vary greatly from planet to planet.

"This framework can also be applied to any other measurements, such as radius, density or water fractions," says study co-author Yann Alibert, Professor of Planetary Science at the University of Bern and the NCCR PlanetS. "Now, for the first time, we have a tool to study planetary systems as a whole and compare them with other systems."

The findings also raise questions: Which architecture is the most common? Which factors control the emergence of an architecture type? Which factors do not play a role? Some of these, the researchers can answer.

A bridge spanning billions of years

"Our results show that 'similar' planetary systems are the most common type of architecture. About eight out of ten planetary systems around stars visible in the night sky have a 'similar' architecture," says Mishra. "This also explains why evidence of this architecture was found in the first few months of the Kepler mission." What surprised the team was that the "ordered" architecture – the one that also includes the solar system – seems to be the rarest class.

According to Mishra, there are indications that both the mass of the gas and dust disk from which the planets emerge, as well as the abundance of heavy elements in the respective star play a role. "From rather small, low-mass disks and stars with few heavy elements, 'similar' planetary systems emerge. Large, massive disks with many heavy elements in the star give rise to more ordered and anti-ordered systems. Mixed systems emerge from medium-sized disks. Dynamic interactions between planets – such as collisions or ejections – influence the final architecture," Mishra explains.

"A remarkable aspect of these results is that it links the initial conditions of planetary and stellar formation to a measurable property: the system architecture. Billions of years of evolution lie in between them. For the first time, we have succeeded in bridging this huge temporal gap and making testable predictions. It will be exciting to see if they will hold up," Alibert concludes.

Artist impression of the four classes of planetary system architecture. A new architecture framework allows researchers to study an entire planetary system at the systems level. If the small planets within a system are close to the star and massive planets further away, such systems have ‘Ordered’ architecture. Conversely, if the mass of the planets in a system tends to decrease with distance to the star these systems are ‘Anti-Ordered’. If all planets in a system have similar masses, then the architecture of this system is ‘Similar’. ‘Mixed’ planetary systems are those in which the planetary masses show large variations. Research suggests that planetary systems which have the same architecture class have common formation pathways.

CREDIT

© NCCR PlanetS, Illustration: Tobias Stierli

Publication details:

L. Mishra, Y. Alibert, S. Udry, C. Mordasini, A framework for the architecture of exoplanetary systems. I. Four classes of planetary system architecture, Astronomy and Astrophysics, Accepted December 2022, https://www.aanda.org/component/article?access=doi&doi=10.1051/0004-6361/202243751

DOI: 10.1051/0004-6361/202243751

L. Mishra, Y. Alibert, S. Udry, C. Mordasini, A framework for the architecture of exoplanetary systems. II. Nature versus nurture: Emergent formation pathways of architecture classes, Astronomy and Astrophysics, Accepted December 2022, https://www.aanda.org/component/article?access=doi&doi=10.1051/0004-6361/202244705       

DOI: 10.1051/0004-6361/202244705

Research Highlight Article in Nature Astronomy:

Maltagliati, L. Finding order in planetary architectures. Nat Astron 7, 8 (20230), https://www.nature.com/articles/s41550-023-01895-0

DOI: 10.1038/s41550-023-01895-0

Bernese space exploration: With the world’s elite since the first moon landing When the second man, "Buzz" Aldrin, stepped out of the lunar module on July 21, 1969, the first task he did was to set up the Bernese Solar Wind Composition experiment (SWC) also known as the “solar wind sail” by planting it in the ground of the moon, even before the American flag. This experiment, which was planned, built and the results analyzed by Prof. Dr. Johannes Geiss and his team from the Physics Institute of the University of Bern, was the first great highlight in the history of Bernese space exploration. Ever since Bernese space exploration has been among the world’s elite, and the University of Bern has been participating in space missions of the major space organizations, such as ESA, NASA, and JAXA. With CHEOPS the University of Bern shares responsibility with ESA for a whole mission. In addition, Bernese researchers are among the world leaders when it comes to models and simulations of the formation and development of planets. The successful work of the Department of Space Research and Planetary Sciences (WP) from the Physics Institute of the University of Bern was consolidated by the foundation of a university competence center, the Center for Space and Habitability (CSH). The Swiss National Fund also awarded the University of Bern the National Center of Competence in Research (NCCR) PlanetS, which it manages together with the University of Geneva.

 

Exoplanets in Geneva: 25 years of expertise crowned by a Nobel Prize The first exoplanet was discovered in 1995 by two researchers from the University of Geneva, Michel Mayor and Didier Queloz, laureates of the 2019 Nobel Prize in Physics.  This discovery allowed the Department of Astronomy of the University of Geneva to be at the forefront of research in the field, with the construction and installation of HARPS on the ESO 3.6m telescope in La Silla in 2003. For two decades, this spectrograph was the most efficient in the world for determining the mass of exoplanets. However, HARPS was surpassed in 2018 by ESPRESSO, another spectrograph built in Geneva and installed on the Very Large Telescope (VLT) in Paranal, Chile. Switzerland has also been involved in space-based observations of exoplanets with the CHEOPS mission, the result of two national expertises: the space know-how of the University of Bern in collaboration with its Geneva counterpart, and the ground-based experience of the University of Geneva assisted by its colleague in the Swiss capital. These two scientific and technical skills have also made it possible to create the National Center of Competence in Research (NCCR) PlanetS.

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JOURNAL

Astronomy and Astrophysics

DOI

10.1051/0004-6361/202243751 

ARTICLE TITLE

A framework for the architecture of exoplanetary systems. I. Four classes of planetary system architecture

ARTICLE PUBLICATION DATE

14-Feb-2023