Sep 20, 2023

Tag team of the James Webb Space Telescope and ALMA captures the core of the most distant galaxy protocluster

An international research team led by Assistant Professor Takuya Hashimoto (University of Tsukuba, Japan) and Researcher Javier Álvarez-Márquez (El Centro de Astrobiología (CAB, CSIC-INTA), Spain) has used the James Webb Space Telescope and the Atacama Large Millimeter/submillimeter Array to observe the most distant galaxy protocluster to date, 13.14 billion light-years away. The team has successfully captured the "core region" of the galaxy protocluster, which corresponds to a metropolitan area with a particularly high number density of galaxies.

The team has revealed that many galaxies are concentrated in a small area and that the growth of galaxies is accelerated. Furthermore, the team used simulations to predict the future of the metropolitan area and found that the region will merge into one larger galaxy within tens of millions of years. These results are expected to provide important clues regarding the birth and growth of galaxies.

The study of how individual stars are born and die in galaxies, how new stars are born from remnants of old stars, and how galaxies themselves grow are important themes in astronomy, as they provide insight into our roots in the Universe. Galaxy clusters, one of the largest structures in the Universe, are the assembly of more than 100 galaxies which are bound together through mutual gravitational force. Observations of nearby galaxies have shown that the growth of a galaxy depends on its environment in the sense that mature stellar populations are commonly seen in regions where galaxies are densely collected. This is referred to as the "environment effect." Although the environment effect has been considered an important piece to understand galaxy formation and evolution, it is not well known when the effect initiated in the history of the Universe. One of the keys to understanding this is to observe the ancestors of galaxy clusters shortly after the birth of the Universe; known as galaxy protoclusters (hereafter protoclusters), these are assemblies of about 10 distant galaxies. Fortunately, astronomy allows us to observe the distant Universe as it was in the past. For example, light from a galaxy 13 billion light-years away takes 13 billion years to reach Earth, so what we observe now is what that galaxy looked like 13 billion years ago. However, light that travels 13 billion light-years becomes fainter, so the telescopes that observe it must have high sensitivity and spatial resolution.

An international research team led by Assistant Professor Takuya Hashimoto (University of Tsukuba, Japan) and researcher Javier Álvarez-Márquez (Spanish Center for Astrobiology) has used the James Webb Space Telescope (JWST, observing visible and infrared light) and the Atacama Large Millimeter/submillimeter Array (ALMA, observing radio waves) to study the "core region" of the protocluster A2744z7p9OD. The protocluster A2744z7p9OD had been announced as the most distant proto-cluster at 13.14 billion light-years away based on observations with JWST by another research group. "However, we have not been able to observe the entire core region, the metropolitan area, with the largest number of galaxy candidates in this protocluster. It was unclear whether the environmental effects of galaxies had begun in this protocluster. So we decided to focus our research on the core region," says Hashimoto.

The research team first observed the core region of this protocluster using JWST. Using NIRSpec, an instrument that observes spectra at wavelengths ranging from visible to near-infrared, the team made integral field spectroscopy observations that can simultaneously acquire spectra from all locations within the field of view. The team has successfully detected ionized oxygen-ion light ([OIII] 5008 Å) from four galaxies in a quadrangle region measuring 36,000 light-years along a side, which is equivalent to half the radius of the Milky Way galaxy (. Based on the redshift of this light (the elongation of the wavelength due to the cosmic expansion), the distance of the four galaxies from the Earth was identified as 13.14 billion light years. "I was surprised when we identified four galaxies by detecting oxygen-ion emission at almost the same distance. The 'candidate galaxies' in the core region were indeed members of the most distant protocluster," says Yuma Sugahara (Waseda/NAOJ), who led the JWST data analysis.

In addition, the research team paid attention to the archival ALMA data, which had already been acquired for this region. The data captures radio emission from cosmic dust in these distant galaxies. As a result of analyses, they detected dust emissions from three of the four galaxies. This is the first detection of dust emission in member galaxies of a protocluster this far back in time. Cosmic dust in galaxies is thought to be supplied by supernova explosions at the end of the evolution of massive stars in the galaxies, which provide the material for new stars. Therefore, the presence of large amounts of dust in a galaxy indicates that many of the first-generation stars in the galaxy have already completed their lives and that the galaxy is growing. Professor Luis Colina (El Centro de Astrobiología (CAB, CSIC-INTA)) describes the significance of the results: "Emission from cosmic dust was not detected in member galaxies of the protocluster outside the core region. The results indicate that many galaxies are clustered in a small region and that galaxy growth is accelerated, suggesting that environmental effects existed only ~700 million years after the Big Bang."

Furthermore, the research team conducted a galaxy formation simulation to theoretically test how the four galaxies in the core region formed and evolved. The results showed that a region of dense gas particles existed around 680 million years after the Big Bang, and shows that four galaxies are formed, similar to the observed core region. To follow the evolution of these four galaxies, the simulation calculated physical processes such as the kinematics of stars and gas, chemical reactions, star formation, and supernovae. The simulations showed that the four galaxies merge and evolve into a single larger galaxy within a few tens of millions of years, which is a short time scale in the evolution of the Universe. "We successfully reproduced the properties of the galaxies in the core region owing to the high spatial resolution of our simulations and the large number of galaxy samples we have. In the future, we would like to explore the formation mechanism of the core region and its dynamical properties in more detail," says Yurina Nakazato, a graduate student at the University of Tokyo, who analyzed the simulation data.

Javier Álvarez-Márquez (Spanish Center for Astrobiology) says, "We will conduct more sensitive observations of the proto-cluster A2744z7p9OD with ALMA to see if there are any galaxies that were not visible with the previous sensitivity. We will also apply the JWST and ALMA observations, which have proven to be very powerful, to more protoclusters to elucidate the growth mechanism of galaxies, and to explore our roots in the Universe."

Read more at Science Daily

Glacier Loss Day indi­cates record break­ing glacier melt

In the summer of 2022, one of Tyrol's largest glaciers experienced its most significant loss of mass on record. Last year, the Hintereisferner in Tyrol, Austria, reached its Glacier Loss Day (GLD) earlier than ever before. The GLD serves as an indicator of a glacier's health throughout the year, similar to how the Earth Overshoot Day measures Earth's resource consumption. Annelies Voordendag, together with a team of glaciologists at the Department of Atmospheric and Cryospheric Sciences at the University of Innsbruck, employs cutting-edge laser scanning techniques to determine the GLD.

The Hintereisferner, located at the back of the Tyrolean Ötztal, has been closely monitored for more than 100 years, and there have been continuous records of its mass balance since 1952. This makes it one of the best-studied glaciers in the Alps and has been key to glacier and climate research at the University of Innsbruck for decades. Since 2016, the researchers have also been surveying the glacier with a worldwide unique system: the surface of the glacier is scanned daily with a terrestrial laser scanner returning the glacier surface elevation changes. This way, the change in the volume of the Hintereisferner is monitored in real time. Innsbruck glaciologist Annelies Voordendag led the measurement on site at the Hintereisferner, the results of the researchers' investigations have now been published as highlighted article in the journal The Cryosphere.

"Already in the early summer of 2022, it became clear that the day when the ice the glacier gained during the winter starts melting away would be reached very soon. We call this day the 'Glacier Loss Day' or GLD for short. It can be compared to the Earth Overshoot Day, which marks the date when we use up more natural resources than the Earth can renew in a year," explains Annelies Voordendag. Monitoring a glacier's volume and mass alterations on a daily basis provides a quick assessment of its condition in a given year.

Observing glaciers' health

When the GLD arrives, it means the glacier is no longer in balance with the natural conditions for that year. The earlier the GLD happens, the more time is left in the remaining summer that the glacier likely will lose volume and thus, mass. "We track the daily volume changes with the automated terrestrial laser scanninng setup overlooking the glacier and derive the day that the mass gained during winter has been lost," says Voordendag. In 2022 the GLD was measured on the 23rd of June. In the two previous years, Glacier Loss Day was reached only in the middle of August.

Read more at Science Daily

Australian woman found with parasitic roundworm in her brain caught from carpet python

The world's first case of a new parasitic infection in humans has been discovered by researchers at The Australian National University (ANU) and the Canberra Hospital after they detected a live eight-centimetre roundworm from a carpet python in the brain of a 64- year-old Australian woman.

The Ophidascaris robertsi roundworm was pulled from the patient after brain surgery -- still alive and wriggling. It is suspected larvae, or juveniles, were also present in other organs in the woman's body, including the lungs and liver.

"This is the first-ever human case of Ophidascaris to be described in the world," leading ANU and Canberra Hospital infectious disease expert and co-author of the study Associate Professor Sanjaya Senanayake said.

"To our knowledge, this is also the first case to involve the brain of any mammalian species, human or otherwise.

"Normally the larvae from the roundworm are found in small mammals and marsupials, which are eaten by the python, allowing the life cycle to complete itself in the snake."

Ophidascaris robertsi roundworms are common to carpet pythons. It typically lives in a python's oesophagus and stomach, and sheds its eggs in the host's faeces. Humans infected with Ophidascaris robertsi larvae would be considered accidental hosts.

Roundworms are incredibly resilient and able to thrive in a wide range of environments. In humans, they can cause stomach pain, vomiting, diarrhoea, appetite and weight loss, fever and tiredness.

The researchers say the woman, from southeastern New South Wales in Australia, likely caught the roundworm after collecting a type of native grass, Warrigal greens, beside a lake near where she lived in which the python had shed the parasite via its faeces.

The patient used the Warrigal greens for cooking and was probably infected with the parasite directly from touching the native grass or after eating the greens.

Canberra Hospital's Director of Clinical Microbiology and Associate Professor at the ANU Medical School, Karina Kennedy, said her symptoms first started in January 2021.

"She initially developed abdominal pain and diarrhoea, followed by fever, cough and shortness of breath. In retrospect, these symptoms were likely due to migration of roundworm larvae from the bowel and into other organs, such as the liver and the lungs. Respiratory samples and a lung biopsy were performed; however, no parasites were identified in these specimens," she said.

"At that time, trying to identify the microscopic larvae, which had never previously been identified as causing human infection, was a bit like trying to find a needle in a haystack.

"In 2022, she began experiencing subtle changes in memory and thought processing and underwent a brain MRI scan which demonstrated an atypical lesion within the right frontal lobe of the brain."

The patient was first admitted to a local hospital in late January 2021 after suffering three weeks of abdominal pain and diarrhoea, followed by a constant dry cough, fever and night sweats. By 2022, the patient was experiencing forgetfulness and depression, prompting an MRI scan.

A neurosurgeon at Canberra Hospital explored the abnormality and it was then that the unexpected eight-centimetre roundworm was found. Its identity was later confirmed through parasitology experts, initially through its appearance and then through molecular studies.

Associate Professor Senanayake said the world-first case highlighted the danger of diseases and infections passing from animals to humans, especially as we start to live more closely together and our habitats overlap more and more.

"There have been about 30 new infections in the world in the last 30 years. Of the emerging infections globally, about 75 per cent are zoonotic, meaning there has been transmission from the animal world to the human world. This includes coronaviruses," he said.

"This Ophidascaris infection does not transmit between people, so it won't cause a pandemic like SARS, COVID-19 or Ebola. However, the snake and parasite are found in other parts of the world, so it is likely that other cases will be recognised in coming years in other countries."

Associate Professor Karina Kennedy said the important message from this case is about general food safety, particularly when gardening or foraging for food where there may be other wildlife in close proximity.

"People who garden or forage for food should wash their hands after gardening and touching foraged products. Any food used for salads or cooking should also be thoroughly washed, and kitchen surfaces and cutting boards, wiped downed and cleaned after use," she said.

The patient continues to be monitored by the team of infectious diseases and brain specialists.

"It is never easy or desirable to be the first patient in the world for anything. I can't state enough our admiration for this woman who has shown patience and courage through this process," Associate Professor Senanayake said.

Read more at Science Daily

Archaeologists discover world's oldest wooden structure

Half a million years ago, earlier than was previously thought possible, humans were building structures made of wood, according to new research by a team from the University of Liverpool and Aberystwyth University.

The research, published in the journal Nature, reports on the excavation of well-preserved wood at the archaeological site of Kalambo Falls, Zambia, dating back at least 476,000 years and predating the evolution of our own species, Homo sapiens.

Expert analysis of stone tool cut-marks on the wood show that these early humans shaped and joined two large logs to make a structure, probably the foundation of a platform or part of a dwelling.

This is the earliest evidence from anywhere in the world of the deliberate crafting of logs to fit together. Until now, evidence for the human use of wood was limited to its use for making fire, digging sticks and spears.

Wood is rarely found in such ancient sites as it usually rots and disappears, but at Kalambo Falls permanently high water levels preserved the wood.

This discovery challenges the prevailing view that Stone Age humans were nomadic. At Kalambo Falls these humans not only had a perennial source of water, but the forest around them provided enough food to enable them to settle and make structures.

Professor Larry Barham, from the University of Liverpool's Department of Archaeology, Classics and Egyptology, who leads the 'Deep Roots of Humanity' research project said:

"This find has changed how I think about our early ancestors. Forget the label 'Stone Age,' look at what these people were doing: they made something new, and large, from wood. They used their intelligence, imagination, and skills to create something they'd never seen before, something that had never previously existed."

"They transformed their surroundings to make life easier, even if it was only by making a platform to sit on by the river to do their daily chores. These folks were more like us than we thought."

The specialist dating of the finds was undertaken by experts at Aberystwyth University.

They used new luminescence dating techniques, which reveal the last time minerals in the sand surrounding the finds were exposed to sunlight, to determine their age.

Professor Geoff Duller from Aberystwyth University said:

"At this great age, putting a date on finds is very challenging and we used luminescence dating to do this. These new dating methods have far reaching implications -- allowing us to date much further back in time, to piece together sites that give us a glimpse into human evolution. The site at Kalambo Falls had been excavated back in the 1960s when similar pieces of wood were recovered, but they were unable to date them, so the true significance of the site was unclear until now."

The site of Kalambo Falls on the Kalambo River lies above a 235 metres (772 foot) waterfall on the border of Zambia with the Rukwa Region of Tanzania at the edge of Lake Tanganyika. The area is on a 'tentative' list from UNESCO for becoming a World Heritage site because of its archaeological significance.

Professor Duller added:

"Our research proves that this site is much older than previously thought, so its archaeological significance is now even greater. It adds more weight to the argument that it should be a United Nations World Heritage Site."

This research forms part of the pioneering 'Deep Roots of Humanity' project, an investigation into how human technology developed in the Stone Age. The project is funded by the UK's Arts and Humanities Research Council and involved teams from Zambia's National Heritage Conservation Commission, Livingstone Museum, Moto Moto Museum and the National Museum, Lusaka.

Read more at Science Daily

Sep 19, 2023

New clues to the nature of elusive dark matter

A team of international researchers, led by experts at the University of Adelaide, has uncovered further clues in the quest for insights into the nature of dark matter.

"Dark matter makes up 84 per cent of the matter in the universe but we know very little about it," said Professor Anthony Thomas, Elder Professor of Physics, University of Adelaide.

"The existence of dark matter has been firmly established from its gravitational interactions, yet its precise nature continues to elude us despite the best efforts of physicists around the world."

"The key to understanding this mystery could lie with the dark photon, a theoretical massive particle that may serve as a portal between the dark sector of particles and regular matter."

Regular matter, of which we and our physical world are made up of, is far less abundant than dark matter: five times more dark matter exists than regular matter. Finding out more about dark matter is one of the greatest challenges for physicists around the world.

The dark photon is a hypothetical hidden sector particle, proposed as a force carrier similar to the photon of electromagnetism but potentially connected to dark matter. Testing existing theories about dark matter is one of the approaches that scientists such as Professor Thomas, along with colleagues Professor Martin White, Dr Xuangong Wang and Nicholas Hunt-Smith, who are members of the Australian Research Council (ARC) Centre of Excellence for Dark Matter Particle Physics, are pursuing in order to gain more clues into this elusive but highly important substance.

"In our latest study, we examine the potential effects that a dark photon could have on the complete set of experimental results from the deep inelastic scattering process," said Professor Thomas.

Analysis of the by-products of the collisions of particles accelerated to extremely high energies gives scientists good evidence of the structure of the subatomic world and the laws of nature governing it.

In particle physics, deep inelastic scattering is the name given to a process used to probe the insides of hadrons (particularly the baryons, such as protons and neutrons), using electrons, muons and neutrinos.

"We have made use of the state-of-the-art Jefferson Lab Angular Momentum (JAM) parton distribution function global analysis framework, modifying the underlying theory to allow for the possibility of a dark photon," said Professor Thomas.

Read more at Science Daily

Why do some environmental shocks lead to disaster while others don't?

It's no longer just about stopping, but how we can live with climate change. To figure this out, we must delve into our cultures, as highlighted in a special issue of The Royal Society. A study by the Complexity Science Hub points out how our history could help guide the way.

Currently, we are grappling with a global crisis convergence. Various types of threats intersect, intertwine, and test our collective resilience, from climate change and economic inequality to political polarization. Although the scale and global reach of these challenges present new hurdles, these threats have been faced and, sometimes, overcome in the past. Societies today barely have time to recover from one crisis to the next, but we possess a significant advantage: knowledge. The knowledge we can obtain from our history through new methods.


CSH researchers Peter Turchin and Daniel Hoyer have pioneered fresh approaches to drawing lessons from history. Together with colleagues from different fields, they have compiled the Crisis Database (CrisisDB) as part of the Global History Databank Seshat, containing over 150 past crises spanning different time periods and regions.

When earthquakes shook the earth, droughts parched the land, or floods ravaged regions, some societies succumbed to social unrest, civil violence, or total collapse, while others exhibited resilience, maintaining essential social functions or even achieving improvement through systemic reforms that promoted well-being and increased democratic participation. Daniel Hoyer remarks, "What we observe is that not every ecological shock or climatic anomaly leads to collapse or even a severe crisis, and not every crisis involves a major environmental stressor." But what makes the difference? What drives collapse versus positive change?


To illustrate the divergent dynamics experienced by past societies, and to highlight the comprehensiveness of their data, the researchers provide three examples. The Zapotec hilltop settlement of Monte Albán in southern Mexico emerged as the most significant settlement in the region. Extreme, persistent drought hit the region in the 9th century, and the once-great site of Monte Albán was entirely abandoned along with many other cities in Mesoamerica. However, recent research presented here shows that this was hardly a case of 'societal collapse', as many former residents of Monte Albán resettled in smaller communities nearby, likely without massive mortality, but rather through an ideological and socio-economic reorientation that also preserved many aspects of their society.

On the opposite end of the spectrum, the immensely wealthy Qing Dynasty in China proved resilient to adverse ecological conditions -- recurrent floods, droughts, swarms of locusts -- during the early part of their reign, but by the 19th century, social pressures had built up leaving them more vulnerable to these same challenges. It was in this period that suffered the Taiping Rebellion, often seen as the bloodiest civil war in human history, and ultimately collapsed completely in 1912 after 250 years of rule. Learn more about the causes in a new study.

In between, the researchers highlight the Ottoman Empire, which faced daunting environmental conditions during the 16th century, including recurrent droughts and the Little Ice Age, leading to social unrest and numerous rebellions led by disgruntled local officials and wealthy families, yet they managed to maintain key social and political structures and avoided collapse, ruling a large swath of territory for several hundreds of years more.


"Many studies typically concentrate on a single event or a specific society. However, it is only by exploring the responses of all, or at least many, societies affected by a particular climate 'regime' that we can ascertain the causal influence and overall effectiveness of the environmental stressor," Peter Turchin says. With this objective in mind, the researchers have developed a methodological framework aimed at producing insights that can be applied to numerous cases across different regions and time periods, helping identify the underlying causes of divergent outcomes.


"The course of a crisis hinges on numerous factors. Environmental forces are undeniably pivotal, but it's not as straightforward as a specific climate event triggering a predetermined societal response," asserts Turchin. Instead, these forces interact with cultural, political, and economic dynamics. Only by comprehending these dynamics can we fathom the interactions. Through their work on the CrisisDB program, the researchers and colleagues aim to unveil these patterns and pinpoint the key factors that either fortify or undermine resilience to contemporary climate shocks.

Read more at Science Daily

Pearl Harbor: Bombed battleships' boost for climate science

Weather data from several ships bombed by Japanese pilots at Pearl Harbor has been recovered in a rescue mission that will help scientists understand how the global climate is changing.

Crew members aboard various vessels -- such as the USS Pennsylvania and the USS Tennessee -- died when their battleships were targeted in December 1941. Despite these losses, many boats returned to service during the Second World War and US naval servicemen continued their daily duties, which included recording weather data.

A new research paper, published in Geoscience Data Journal, tells the story of the recovery of World War II weather data that comes from 19 US Navy ships. Its rescue was made possible thanks to the hard work of over 4,000 volunteers who transcribed more than 28,000 logbook images from the US Navy fleet stationed at Hawai'i from 1941-1945. Previous studies have suggested these years were abnormally warm. The new dataset, encompassing over 630,000 records with more than 3 million individual observations, will help to show whether this was the case.

Dr Praveen Teleti, the University of Reading research scientist who led the research, said: "Disruptions to trade routes in World War II led to a significant reduction in marine weather observations. Until recently, records from that time were still only available in classified paper documents. The scanning and rescuing of this data provides a window into the past, allowing us to understand how the world's climate was behaving during a time of tremendous upheaval.

"There are two sets of people we need to thank for making this mission a success. We are very grateful to the global team of citizen scientists for transcribing these observations and creating a huge dataset that includes millions of entries about air and sea surface temperatures, atmospheric pressure, wind speed, and wind direction.

"The greatest respect must go to the brave servicemen who recorded this data. War was all around them, but they still did their jobs with such professionalism. It is thanks to their dedication and determination that we have these observations 80 years on."

Data from devastated ships

The logbooks used in the project come from 19 different ships, including battleships, aircraft carriers, destroyers, and cruisers, most of which played pivotal roles in World War II events. Many ships that data was recovered from were present at Pearl Harbor during the attack by Japanese bombers on 7 December 1941, although all ships listed in the study saw action in the Pacific at some point during the war. USS Pennsylvania was hit when Pearl Harbour was attacked by the Japanese air force in December 1941. One bomb fell on the battleship and caused the deaths of nine servicemen, but it remained in service. The USS Tennessee was bombed twice in December 1941, resulting in the death of five servicemen. It returned to service in February 1942.

Future climate studies

Observations from naval vessels were the primary sources of marine observations for the World War II period but many records were destroyed as an act of war, or simply forgotten due to the length of time they were considered classified.

The recovered dataset reveals how wartime necessitated changes in observation practices. For example, more observations were taken during daytime than nighttime to reduce exposure to the enemy ships and avoid being detected. It is believed that changes such as this could have led to slightly warmer temperatures being recorded, meaning today's history books show a period of abnormal warmth in global datasets during World War II. The new data will help resolve this uncertainty.

Read more at Science Daily

Mature sperm lack intact mitochondrial DNA

New research provides insight about the bedrock scientific principle that mitochondrial DNA -- the distinct genetic code embedded in the organelle that serves as the powerplant of every cell in the body -- is exclusively passed down by the mother.

The study, a collaboration among Oregon Health & Science University and other institutions, published today in the journal Nature Genetics.

Scientists have long recognized the fact that mitochondrial DNA, or mtDNA, comes exclusively from egg cells in humans, meaning only the mother contributes the genetic code carried by thousands of mitochondria necessary for energy production in every cell in the body.

Previously, it was believed that paternal mtDNA was eliminated soon after a sperm fuses with an oocyte, or developing egg, during fertilization, possibly through an immune-like search-and-destroy response.

However, the study found that while mature sperm do carry a small number of mitochondria, they lack intact mtDNA.

"We found that each sperm cell does bring 100 or so mitochondria as organelles when it fertilizes an egg, but there is no mtDNA in them," said co-author Shoukhrat Mitalipov, Ph.D., director of the Center for Embryonic Cell and Gene Therapy at OHSU.

Researchers found that sperm cells are not only devoid of intact mtDNA, but they also lacked a protein essential for mtDNA maintenance, known as mitochondrial transcription factor A, or TFAM.

Scientists aren't sure why sperm are not allowed to contribute mtDNA, but Mitalipov theorizes that it may relate to the fact that a sperm uses a lot of mitochondrial energy in its biological impetus to fertilize an egg. It would thus accumulate mutations in mtDNA. The developing eggs known as oocytes, by contrast, draw energy primarily from surrounding cells, not from their own mitochondria, so maintain relatively pristine mtDNA.

"Eggs pass on really good mtDNA at least partly because they don't use mitochondria as a source of energy," Mitalipov said.

The 100 or so organelles in sperm are swamped by hundreds of thousands of mitochondria embedded in each egg cell -- each carrying the 37 genes in mitochondrial DNA. The contribution of only maternal mtDNA is believed to confer an evolutionary advantage by limiting the risk of accumulations of mtDNA mutations that cause disease in offspring.

Mitochondria control respiration and energy production within every cell of the body, so mutations in mtDNA can cause a range of potentially fatal disorders affecting organs with high-energy demands, such as the heart, muscle and brain.

To help mothers prevent passing on known mtDNA disorders to their children, Mitalipov pioneered a method called mitochondrial replacement therapy to replace mutant mtDNA through in vitro fertilization using healthy mtDNA from donor eggs.

Congress has prevented the Food and Drug Administration from overseeing clinical trials using the procedure in the U.S., so clinical trials are instead being conducted overseas, including clinical trials in the United Kingdom to prevent disease and in Greece to treat infertility.

Read more at Science Daily

Sep 18, 2023

New findings suggest Moon may have less water than previously thought

A team including Southwest Research Institute's Dr. Raluca Rufu recently calculated that most of the Moon's permanently shadowed regions (PSRs) are at most around 3.4 billion years old and can contain relatively young deposits of water ice. Water resources are considered key for sustainable exploration of the Moon and beyond, but these findings suggest that current estimates for cold-trapped ices are too high.

The current tilt of the Moon's spin axis combined with its orbital inclination -- the angle to Earth's orbital plane -- and the Sun's low angle creates permanent shadows at its poles. PSRs are some of the coldest spots in the solar system, allowing them to trap volatile chemicals, including water ice, that would immediately transform directly from a solid to a gas in the harsh, airless sunshine that falls in most other places on the Moon.

"We think the Earth-Moon system formed following a giant impact between early Earth and another protoplanet," said Rufu, a Sagan Fellow who is the second author of a Science Advances paper. "The Moon formed from the impact-generated debris disk, migrating away from Earth over time. Around 4.1 billion years ago the Moon experienced a major spin axis reorientation when its tilt reached high angles before it damped down to the configuration we see today. As the axial tilt decreased, PSRs appeared at the poles and grew over time."

The team used AstroGeo22, a new Earth-Moon evolution simulation tool, to calculate the Moon's axial tilt over time. Together with surface height measurements from the Lunar Orbital Altimeter Laser data (LOLA), the team estimated the evolution of the shadowed areas over time.

"The time evolution of the Moon-Earth distance remained an unsolved problem for half a century," Rufu said. "However, these new geological proxies for the history of the Earth-Moon system allow us to calculate the Moon's axial tilt and the extent of PSRs over time."

In 2009, NASA crashed the two-ton Atlas Centaur rocket body, part of the Lunar Crater Observation and Sensing Satellite (LCROSS), near the south pole of the Moon. It struck the floor of Cabeus crater, creating a plume of debris examined for the presence of water and other chemicals in the lunar regolith. A shepherding satellite travelling four minutes behind the Centaur and several Earth-orbiting satellites, including the Hubble Space Telescope, monitored the impact.

"Our work suggests that Cabeus crater became a PSR less than a billion years ago. The various volatiles detected in the plume created by LCROSS indicate that ice-trapping continued into relatively recent times," said Norbert Schörghofer, the lead author of this paper from the Planetary Science Institute. "Impacts and outgassing are potential sources of water but peaked early in lunar history, when the present-day PSRs did not yet exist. The age of PSRs largely determines the amount of water ice that could be trapped in the lunar polar regions. Information about the abundance of water ice in PSRs is particularly important in planning for upcoming crewed and uncrewed missions to the Moon searching for water."

Read more at Science Daily

Brilliant galaxies of early universe

Rochester Institute of Technology scientists have once again used data from the James Webb Space Telescope (JWST) as part of the Cosmic Evolution Early Release Science (CEERS) Survey to change the way we think about the universe and its distant galaxies.

Jeyhan Kartaltepe, associate professor in the School of Physics and Astronomy, and Rebecca Larson, postdoctoral research associate, co-authored a paper, "Confirmation and refutation of very luminous galaxies in the early Universe," published in Nature confirming very bright galaxies in the early universe, while also disproving the identification of what would have been the most distant galaxy ever found.

Kartaltepe and Larson, along with co-authors from around the world, studied the redshift (or displacement of the spectrum of an object toward longer, red wavelengths) of several specific galaxies to see how much the light shifted, which indicates how far away the galaxies are. The CEERS team focused on Maisie's Galaxy, which was theorized to have a redshift of z ≈ 11.5, while a team in Scotland researched a nearby galaxy that they believed could have a redshift of z ≈ 16, far larger than any ever found before.

To examine further, the two teams partnered on a proposal to receive follow-up spectroscopy. When the new data came in, the teams were able to precisely measure the redshifts of both of these candidates, along with a few others.

"Spectra are how you really confirm what a galaxy's redshift is," explained Kartaltepe. "For these two galaxies, the answer was very clear -- the spectra look completely different. We confirmed that Maisie's Galaxy is at the high redshift we thought it was."

The group also found that because of a coincidence that mimicked the colors of a high redshift galaxy, the other galaxy is not at a redshift of z ≈ 16, but at a redshift of z ≈ 4.9. Both the initial and follow-up data from JWST turned the theories into discoveries.

"Not only did JWST find these galaxies we didn't know about before, but then it confirmed the redshift for them," said Larson. "This paper in particular speaks to the power of not only JWST finding galaxies in the really early universe but also confirming and characterizing them."

The research and the paper would not have been possible without dedicated collaboration between the CEERS team and the team in Scotland. Instead of working separately on their individual galaxies and submitting separate proposals, the partnership allowed for the follow-up spectroscopy to be accepted, and the subsequent analysis to be conducted efficiently, leading to new information about the universe.

When researching the data from JWST, scientists aim to find the highest redshift galaxies, or the most distant galaxies. Finding galaxies in the very early universe was one of the goals for the JWST. These and other early discoveries have proven the success of the telescope, even this early in its existence.

Read more at Science Daily