среда, 24 октября 2018 г.

Studying the hotbed of horizontal gene transfers

For over 200,000 years, humans and their gut microbiomes have coevolved into some of the most complex collections of living organisms on the planet. But as human lifestyles vary from the urban to rural, so do the bacterial diversities of gut microbiomes.











Studying the hotbed of horizontal gene transfers
A woman in Ghana carries a basket of fish. Local diets and lifestyles have created a remarkable
diversity in the human microbiome worldwide [Credit: Mathieu Groussin]

That’s why a nonprofit global collaboration of more than 70 scientists has been working for the past two years to interrogate and preserve that diversity of gut microbiomes from populations around the world, racing against the proliferation of antibiotic overuse and Western-style diets, which are known to contribute to a decrease in gut bacterial diversity. The Global Microbiome Conservancy, launched in 2016, already has some surprising insights that further shed light on the black box of gut bacterial diversity and human digestion.


The MIT-based scientists who founded the conservancy come from a disparate set of disciplines: biological engineering, evolutionary biology, organic geochemistry, and biomedical research. Such collaborations may allow for interdisciplinary innovation that stands to improve the understanding of the science within our guts, says Mathilde Poyet, a postdoc in the Department of Biological Engineering’s Alm Lab. Poyet believes the interdisciplinary nature of the collaboration promotes the conservancy’s goals, which she says are to “preserve the full biodiversity of the human gut microbiome before it is lost, and to advance our understanding of the origins and functions of the human gut microbiomes,” within a “robust research ecosystem.”


Poyet and fellow MIT-based postdocs Mathieu Groussin, who also works in the Alm Lab, and Ainara Sistiaga, a Marie Curie Postdoctoral Fellow in the Summons Lab within the Department of Earth, Atmospheric and Planetary Sciences (EAPS), presented the preliminary results of their work at the first MIT Microbiome Club meeting of the 2018-19 academic year. At the meeting, Poyet, Groussin, and Sistiaga spoke about their research progress as well as what’s surprised them most so far.


In addition to biobanking and characterizing bacterial isolates collected from fecal samples from around the world, Poyet focuses on the horizontal exchange of genetic materials between living organisms, known as horizontal gene transfer (HGT). Unlike vertical transfers, horizontal gene transfers are acquisitions of genetic material from non-parental lineages.


“Transfers of genes are known to be crucial for bacterial evolution and the human gut microbiome is an important hotbed for horizontal gene transfers,” Poyet says. “But all previous studies fell short at characterizing the timescale of these HGT events.”


With the collection of bacterial isolates and genomes she built, Poyet is now able to identify evidence of very recent horizontal gene transfers, supporting the notion that these transfers frequently occur during the human lifetime. The effects of highly active horizontal gene transfers mean that gut bacteria could experience a sort of turnover of genetic material over time, which the conservancy hopes to study further as they collect more data.











Studying the hotbed of horizontal gene transfers
Harvesters gather crops on a farm in Rwanda. The Global Microbiome Conservancy’s current studies focus on samples
collected from 19 distinct populations sampled from sub-Saharan countries, Arctic regions, and North America
[Credit: Christopher Corzett]

From additional preliminary analysis, Poyet and Groussin have found that in industrialized populations, which tend to have less gut bacterial diversity, meaning the rate of gene exchange through horizontal gene transfer is greater. “As HGT is a mechanism frequently used by bacteria to rapidly adapt to changing environments, this result suggests that an industrialized lifestyle imposes a stronger selective pressure on the gut microbiome of individual people, possibly as a result of the high consumption of antibiotics,” Poyet says.


Ainara Sistiaga has been zeroing in on a dietary element that could also have implications for gastrointestinal bacteria and human health: lipids. Lipids, the hydrophobic biomolecules often referred to as fats, are unexplored in the gut microbiome. Sistiaga aims to change that.


With fecal samples collected through the conservancy, Sistiaga performs lipid analysis—a series of chemistry-rooted procedures that help researchers characterize which lipids are present as well as their abundances.


One lipid of particular interest is cholesterol, a molecule widely implicated in heart disease and stroke. As meat-heavy diets increase in popularity around the world, global cholesterol intake is set to rise as well. Theoretically, in most humans, some of the cholesterol that reaches the gut should undergo a bacterial conversion into a byproduct that the body cannot reabsorb and would be excreted. But Sistiaga finds that all gut microbiomes execute metabolic functions differently. “What we have observed is that most of the participants in rural populations are performing this conversion much more efficiently than Western donors,” Sistiaga says. So, in order to describe and understand how such processes work within the gut, Sistiaga hopes to use methods informed from organic geochemistry to characterize the fate of cholesterol in humans from around the world.


After the presentation, the MIT researchers fielded questions from the audience. “People were interested in all aspects of the presentation—traveling, how to get involved, the science, the preliminary results, the potential outcomes of this project,” Sistiaga says. “Even after the Q&A, a lot of people approached us for more specific questions.”


As part of its efforts, the Global Microbiome Conservancy establishes long-term collaborations with local populations and researchers for sampling and analysis—and the participants themselves maintain ownership of their samples. Within the next two years, the conservancy is set to increase its global coverage. The current microbiome studies conducted focus on samples collected from 19 distinct populations sampled worldwide from Arctic regions, sub-Saharan countries and North America, but they’ll soon be complemented with samples from Malaysia and Peru. Poyet adds, “We anticipate [samples from Asia and South America] will yield novel and unique microbial communities that must be preserved.”


“It’s been exciting to unveil the microbiome of these underrepresented communities, and I think we are just seeing the tip of the iceberg,” Sistiaga says. “Everything we’ve observed so far confirms how important and truly urgent this work is.”


Author: Fatima Husain | Source: Massachusetts Institute of Technology [October 22, 2018]



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Tortoise evolution: How did they become so big?

Tortoises are a group of terrestrial turtles globally distributed in habitats ranging from deserts to forests and include species such as the Greek and the Galapagos tortoise. Some species evolved large body sizes with a shell length exceeding 1 metre whereas others are no larger than 6-8 centimetres. Despite a particular interest from naturalists ever since the times of Darwin, the evolution of gigantism in tortoises remains enigmatic.











Tortoise evolution: How did they become so big?
Fossil tortoise at the Central Natural Science Collections at MLU
[Credit: Markus Scholz/MLU]

The fact that all living giant tortoises are insular may suggest that their evolution followed the so-called island rule: a trend toward dwarfism of large animals and gigantism of small animals on islands. An example of insular dwarfism is the Florida key deer, a dwarf version of the mainland white-tailed deer; its small size may be an adaptation to the limited resources found on the islands. Insular gigantism is best exemplified by the famous dodo, an extinct flightless pigeon from Mauritius, probably evolving large body size due to release from predatory pressure. Previous studies on extant tortoises were partly inconclusive: giant size has been linked to the absence of predatory mammals in islands but it has been also proposed that tortoises were already giants when they reached the remote archipelagos. Since very few giant tortoise species survive to the present, these hypotheses are impossible to test without analysing extinct species through the help of the fossil record.
In a recent study in the journal Cladistics, Dr Evangelos Vlachos from the Paleontological Museum of Trelew, Argentina, and Dr Márton Rabi from the Martin Luther University Halle-Wittenberg (MLU), funded by the German VolkswagenStiftung, assembled the most comprehensive family tree of extinct and extant tortoises so far. The researchers analysed genetic data from living species together with osteological data from fossil and living tortoises.


This is the first study of such global scale to allow for investigating body size evolution in tortoises. The fossils reveal a very different picture of the past compared to the present. Giant size evolved on multiple occasions independently in mainland Asia, Africa, Europe, North and South America at different times of Earth history. However, all of these species went extinct at latest during the Pleistocene ice age.


“The fossils highlight a great number of extinct mainland giant species and suggest that the evolution of giant size was not linked to islands,” says Dr Evangelos Vlachos.


Instead, living insular giant tortoises, such as the ones from Galapagos and Seychelles, more likely represent survivors of unrelated giant species that once inhabited South America, East Africa, and/or Madagascar.


“Giant tortoises may have been better island colonizers because they can tolerate water and food shortage during an oceanic dispersal for a longer period than smaller species. Giant tortoises have been reported to survive 740 km of floating in the ocean,” says Dr Márton Rabi.


What led to the extinction of these mainland giants remains enigmatic. For the ice age species, it may have been a combination of predatory (including human) pressure and climate change. It is likewise unclear, if not the island rule, then what is driving tortoises to repeatedly evolve into giant forms?


“We expect that warmer climate and predator pressure plays a role in the evolution of giant size but the picture is complex and our sampling of the fossil record is still limited.” – Vlachos adds.


An unexpected outcome of the study was that the Mediterranean tortoises (familiar due to their popularity as pets) actually represent a dwarf lineage as their ancestors turned out to be considerably larger.


“Tortoises have been around for more than 55 million years and we are now able to better understand the evolution of this successful group. Today, however, out of the approximately 43 living species 17 are considered endangered and many more are vulnerable largely due to human-induced habitat loss; this is a disappointing fact.” – Rabi points out.


Source: Martin-Luther-University Halle-Wittenberg [October 23, 2018]



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9,000-year-old seal unearthed in southern Turkey

An ancient seal dating back to some 9,000 years ago was unearthed at a mound in the southern coastal Turkish city of Mersin.











9,000-year-old seal unearthed in southern Turkey
Credit: AA

The seal – dating back to 7,000 BC – was uncovered in excavations at Yumuktepe Höyük, located four kilometers west of the city center.
During the two-and-a-half month excavations in the mound, the team of 25 – led by Isabella Caneva, an archaeology professor at Italy’s Lecce University – discovered an arrowhead belonging the Neotlithic era and scores of sling stones in addition to the seal.


The seal is incised with geometric patterns was used to mark ownership of property, or perhaps even provenance in a developing trade system.


“The obsidian arrowhead which belongs to the Neolithic period was removed and a large number of sling stones which were used for counting the Chalcolithic layer with a geometric pattern seal were discovered,” Caneva said.


The team acquired a great deal of information about the region’s history during the excavation, she added.


Source: Anadolu Agency [October 23, 2018]



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Bronze Age dagger unearthed in Slovakia

A local man has found a unique Bronze Age dagger on the banks of the Slanec stream in Hriňová. The dagger is probably between 3200 and 3600 years old. More specific data will be available after more detailed research by preservation offices.











Bronze Age dagger unearthed in Slovakia
Credit: Jozef Poliak, TASR

“It is the oldest finding from the area around our town and may reveal significant new historical connections to the region,” said the Hriňová project manager, Michal Machava, as quoted by the TASR newswire.


Until now, Roman coins from the first century have been the oldest discoveries from the area.


The bronze dagger was particularly well preserved and was handed to the Regional Monument Board in Banská Bystrica.


Archaeologist Ján Beljak from the Zvolen department of the Archaeological Institute of the Slovak Academy of Sciences in Nitra said that the finding is unique because nothing from this time period has ever been found in the mountain area of Hriňová before.


“We are assuming that in the future we will also discover a Bronze Age settlement in the same vicinity,” he said, as quoted by TASR.


Source: The Slovak Spectator [October 23, 2018]



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6,4 Million Euros for research into the birth of agriculture in Europe

An interdisciplinary team from the universities of Bern, Oxford and Thessaloniki was awarded a grant of 6.4 million euros from the European Research Council (ERC). The team included researchers from the fields of archaeology and biology. They received one of the highly competitive “ERC Synergy Grants”. Aided by studies conducted in the lakes in Greece and in the south of the Balkans, the project should show how the climate, environment and agriculture have developed over the last 10,000 years and what influences these factors have had on each other.











6,4 Million Euros for research into the birth of agriculture in Europe
Platform for exploration drilling of the University of Bern for sea sediments at Lake Kastoria, 2017 
[Credit: © University of Bern/André Lotter]

The lakes in the north of Greece and in the south of the Balkans are a unique archive of European cultural and environmental history which have hardly been explored until now. Now this international team, created at the initiative of the University of Bern, wants to use this treasure trove of information.
The five-year project is named EXPLO (Exploring the dynamics and causes of prehistoric land use change in the cradle of European farming) and will break new ground by combining underwater archaeology with methods used by ecologists, biologists and climate scientists for the very first time. And it employs dynamic computer models in order to reconstruct the interaction between the climate and humans. The aim is to try to understand the adjustment strategies used by early farming communities to react to changing climate and environmental conditions.











6,4 Million Euros for research into the birth of agriculture in Europe
Example of a sea sediment core (here from Lake Moossee near Bern): yearly layered sediment, around 3800-3600 BC. 
At that time, a settlement of the western Switzerland Cortaillod Culture was situated near a present-day 
swimming pool at Lake Moossee [Credit: © University of Bern/Fabian Rey]

This innovative approach won over the experts on the European Research Council. EXPLO is one of 27 European projects that has been awarded an “ERC Synergy Grant” this week. This grant is the highest level of the Excellence Funding of the European Commission. The generously equipped funding instrument supports interdisciplinary projects, which must satisfy the highest scientific criteria, and is highly coveted among researchers.


Less than 10 percent of the applications submitted are approved. The “Synergy Grant” was given out for the second time and was awarded to the University of Bern for the first time. EXPLO was initiated by Albert Hafner, professor of prehistoric archaeology, and Willy Tinner, professor of paleoecology, both from Bern. Professors Amy Bogaard and Kostas Kotsakis, from the Universities of Oxford and Thessaloniki respectively, are also involved in the project.











6,4 Million Euros for research into the birth of agriculture in Europe
Diving work in staked out squares in front of the reconstruction of the Ploča settlement at Lake Ohrid 
[Credit: © University of Bern/Marco Hostettler]

The cradle of European agriculture


Albert Hafner has made a name for himself internationally as a prehistorian and specialist in lakeside settlements and underwater archaeology, amongst other things. The UNESCO World Heritage Site “Prehistoric Pile Dwellings around the Alps”, comprising of 111 sites in the six Alpine states, is an initiative that Albert Hafner came up with. The shores of roughly a dozen lakes in the South Balkans were settled during the Neolithic period and the Bronze Age.


But in comparison to the excavation sites which have been explored in the Alps over the past 150 years, very little is known about these lakeside settlements. “The excavation sites which have virtually not been studied at all until now are of outstanding scientific value”, explains Albert Hafner. “They could prove to be just as important as Neolithic and Bronze Age lakeshore settlements around the Alps.”











6,4 Million Euros for research into the birth of agriculture in Europe
Recovering wooden samples at Ploča [Credit: © University of Bern]

EXPLO wants to examine prehistoric settlement sites in lakes and shore zones. Here, thousands of wooden building structures have been preserved. This wood is used as a base for dendrochronology, a method which uses the growth rings of oak and conifer trees to work out the age of the wood. This method allows for a highly precise dating and is the backbone of the project.


Excavations and sample collections are planned in the large lakes; Ohrid, Prespa and Orestiada. All of these sites are in an incredibly interesting historico-cultural area: the cradle of European agriculture. Here, agricultural techniques from Western Asia reached Europe over 8,000 years ago. The analysis of lake sediments should show how land use and also how the climate conditions in this region have changed over time.



Underwater archaeological work at Lake Ohrid in a prehistoric settlement with layers from the Neolithic and the Bronze Age 


in a water depth of about 4m [Credit: © University of Bern/Marco Hostettler]


Learning from prehistoric farmers


Willy Tinner is a world-leading paleoecologist who has studied climate and vegetation history in many regions of the world. He wants to draw useful lessons for the future from the eventful past. “The aim of EXPLO is to understand the complex relationship between the prehistoric people and their environment”, says Tinner, “and to gain new information about the long-term consequences that the transition to agriculture had on the ecosystem.”


Conversely, the project should also show how early agriculture coped with environmental changes. Knowledge about how human societies reacted to such challenges in the past is becoming increasingly important in view of the effects of climate change happening at the moment.











6,4 Million Euros for research into the birth of agriculture in Europe
Tagged piles at Ploča [Credit: © University of Bern]

The project that has been awarded funding from the European Commission is the result of years of research and establishing and maintaining contacts. Albert Hafner built a scientific network in the Southern Balkans through projects funded by the Swiss National Fund, and trained underwater archaeologists on-site.
Teams from the University of Bern performed test drillings and excavations in the lakes in Northern Greece and in Lake Ohrid in 2016 and 2018. These tests showed that the sediment cores collected represented an incredibly rich environmental archive and that the archaeological sites were of the highest quality.











6,4 Million Euros for research into the birth of agriculture in Europe
Wood samples from Lake Ohrid [Credit: © University of Bern]

Albert Hafner and Willy Tinner are members of the Oeschger Centre for Climate Change Research (OCCR) at the University of Bern. Their interdisciplinary orientation will be vitally important when it comes to the evaluation of the data sources collected as part of EXPLO. More than 1000 radiocarbon datings will be carried out in the OCCR’s C14 dating laboratory.


Source: University of Bern [October 23, 2018]



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Five skeletons found at Pompeii

The remains of five people, probably two women and three children, were found in a bedroom in Pompeii on Wednesday.











Five skeletons found at Pompeii
Credit: Pompeii – Parco Archeologico/ANSA

The group probably took refuge in the bedroom in a desperate attempt to escape a shower of volcanic rocks that had filled the house, Pompeii director Massimo Osanna told ANSA.
“It’s a shocking discovery, but also very important for the history of studies,” Osanna said.


Five skeletons found at Pompeii

Five skeletons found at Pompeii

Five skeletons found at Pompeii


Five skeletons found at Pompeii

Five skeletons found at Pompeii

Five skeletons found at Pompeii










Five skeletons found at Pompeii
Credit: Pompeii – Parco Archeologico/ANSA

The skeletons were found in a house where a charcoal inscription was recently found backing the theory that the Mount Vesuvius eruption that destroyed the ancient Roman city took place in October of 79 AD, not August.
New excavations have taken place at the site, in the Regio V of Pompeii.


Source: ANSA [October 24, 2018]



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Sensing Victory This video shows a zebrafish embryo as it…


Sensing Victory


This video shows a zebrafish embryo as it develops an elaborate network of neurons, the sensory nervous system, which will allow it to make sense of the world around it. Sights, smells and tastes are detected by receptors then encoded into electronic signals that are transmitted along the wire-like axons of sensory neurons. Captured here, developing axons are sprouting upwards, away from the circular cell body of each neuron. The axons form an elaborate, spider-web like network. Sixteen hours of time-lapse footage were sped-up to form this short clip. It was captured with an unconventional microscope technique that allowed the embryo to grow in water, its natural environment. This was more challenging than standard techniques that typically hold specimens in place during filming. Such high-quality footage helps researchers to investigate how healthy neurons develop and what might go wrong in neurodegenerative diseases.


Written by Deborah Oakley



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Copernicus Sentinel-5P reveals new nasties


ESA – Sentinel-5P Mission logo.


24 October 2018



Sentinel-5P

With air quality a serious environmental health problem, the Copernicus Sentinel-5P satellite is tasked with mapping air pollutants around the entire globe every day. This new mission has been providing data on carbon monoxide, nitrogen dioxide and ozone since July and now other polluting nasties such as sulphur dioxide and formaldehyde have joined the list of data products available to monitor the air we breathe.


Air pollution affects people in developed and developing countries alike. In Europe alone, it is estimated that every year 400 000 people die prematurely because of poor air quality.



Formaldehyde

Satellite data and computer models are the only real way of showing how pollution accumulates around the world as a whole. In the immediate term, these tools are essential for forecasts and warnings on air quality. In the longer term they are indispensable for providing accurate information for decision-makers developing strategies to tackle this major problem.


Launched in October 2017, Copernicus Sentinel-5P – short for Sentinel-5 Precursor – is the first Copernicus satellite dedicated to monitoring our atmosphere. It is part of the fleet of Copernicus Sentinel missions that ESA develops for the European Union’s environmental monitoring programme.


The satellite carries an advanced multispectral imaging spectrometer called Tropomi. What sets Tropomi apart is that it detects the unique fingerprints of atmospheric gases in different parts of the electromagnetic spectrum to image a wide range of pollutants more accurately and at a higher spatial resolution than ever before.


Since this state-of-the art satellite mission was launched, scientists have been carefully evaluating its data and, in turn, releasing the data to users.


Streams of data on carbon monoxide, nitrogen dioxide, ozone, along with information on aerosols and clouds have been available since July. On 17 October, sulphur dioxide and formaldehyde joined the list of air pollutants routinely available for services such as air-quality forecasting and volcanic ash monitoring.



Sulphur dioxide

The Copernicus Atmospheric Monitoring Service is a key user of these data products.


Head of the service, Vincent-Henri Peuch, said, “Even looking at social media, we see that Copernicus Sentinel-5P is proving to be a great ambassador for environmental monitoring and for taking action on air pollution. But the mission does much more than give us images.


“This is a sophisticated mission designed to measure the comprehensive set of atmospheric constituents for underpinning several of the CAMS information products. We are already using observations of ozone and nitrogen dioxide, which have been available routinely since July.


“We are really excited about using these new sulphur dioxide and formaldehyde data in our operational services. Copernicus Sentinel-5P data is also about to make its way into everyone’s pockets as our products are being taken up by leading smartphone applications to inform the public on current air quality.”


Sulphur dioxide affects air quality badly and can lead to breathing problems. While it is released into the atmosphere mainly through industrial processes, it is also present in volcanic plumes.


Monitoring the spread of volcanic plumes is critical for aircraft safety.



Sulphur dioxide from Fuego volcano



Nicolas Theys from the Royal Belgian Institute for Space Aeronomy said, “Copernicus Sentinel-5P’s near-realtime data on sulphur dioxide and aerosols are being used in the Support to Aviation Control Service and in the European Natural Disaster Coordination Information System for Aviation.


“The unprecedented level of details offered by the mission allows Volcanic Ash Advisory Centre users to better track and forecast the dispersion of volcanic plumes.”


The latest data release also includes formaldehyde, which tends to enter the atmosphere from forest fires and wood processing, for example. It is an important intermediate gas in the oxidation of methane and other hydrocarbons. While it is short-lived in the atmosphere, it reacts chemically to become a major source of carbon monoxide – another harmful pollutant.


Improved total ozone columns are now also available to enable long-term ozone monitoring from space.


Each of the Copernicus Sentinel missions carries state-of-the-art technology to deliver a stream of complementary imagery to help manage the environment effectively and respond to global change. The European Commission leads the Copernicus programme. ESA is responsible for the space component, which includes the family of Copernicus Sentinel satellite missions. Data are used worldwide and are free of charge.



Ozone hole over Antarctica

Josef Aschbacher, Director of ESA’s Earth Observation Programmes, underlined, “The Copernicus Sentinel-5P mission is a prime example of how Europe works together for the benefit of its citizens.


“The European Commission as leader of the Copernicus programme, ESA as the coordinator, developer and operator of the space component are, together with the respective Member States, the prime drivers of Copernicus.


“In the case of Sentinel-5P, the Tropomi instrument provided by The Netherlands highlights the tight cooperation across Europe. Copernicus is indeed a success story for Europe in space.”


Related links:


Sentinel-5P: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus/Sentinel-5P


Copernicus: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus


Copernicus Atmosphere Monitoring Service: http://atmosphere.copernicus.eu/


Netherlands Space Office: http://www.spaceoffice.nl/en/


Royal Netherlands Meteorological Institute: http://www.knmi.nl/over-het-knmi/about


DLR: http://www.dlr.de/dlr;internal&action=_setlanguage.action?LANGUAGE=en


Royal Belgian Institute for Space Aeronomy: http://www.aeronomie.be/en/index.htm


BIRA Support to Aviation Control Service: http://sacs.aeronomie.be/


European Natural Disaster Coordination and Information System for Aviation: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus/Sentinel-5P/www.eunadics.eu


Images, Animation, Text, Credits: ESA/Contains modified Copernicus data (2018), processed by BIRA–IASB/DLR.


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NASA’s Juno Mission Detects Jupiter Wave Trains


NASA – JUNO Mission logo.


October 24, 2018


Massive structures of moving air that appear like waves in Jupiter’s atmosphere were first detected by NASA’s Voyager missions during their flybys of the gas-giant world in 1979. The JunoCam camera aboard NASA’s Juno mission to Jupiter has also imaged the atmosphere. JunoCam data has detected atmospheric wave trains, towering atmospheric structures that trail one after the other as they roam the planet, with most concentrated near Jupiter’s equator.



Image above: Three waves can be seen in this excerpt of a JunoCam image taken on Feb. 2, 2017, during Juno’s fourth flyby of Jupiter. The region imaged in this picture is part of the visibly dark band just north of Jupiter’s equator known as the North Equatorial Belt. Image Credits: NASA/JPL-Caltech/SwRI/MSSS/JunoCam.


The JunoCam imager has resolved smaller distances between individual wave crests in these trains than ever seen before. This research provides valuable information on both the dynamics of Jupiter’s atmosphere and its structure in the regions underneath the waves.


“JunoCam has counted more distinct wave trains than any other spacecraft mission since Voyager,” said Glenn Orton, a Juno scientist from NASA’s Jet Propulsion Laboratory in Pasadena, California. “The trains, which consist of as few as two waves and as many as several dozen, can have a distance between crests as small as about 40 miles (65 kilometers) and as large as about 760 miles (1,200 kilometers). The shadow of the wave structure in one image allowed us to estimate the height of one wave to be about 6 miles (10 kilometers) high.”


Most of the waves are seen in elongated wave trains, spread out in an east-west direction, with wave crests that are perpendicular to the orientation of the train. Other fronts in similar wave trains tilt significantly with respect to the orientation of the wave train, and still other wave trains follow slanted or meandering paths.


“The waves can appear close to other Jovian atmospheric features, near vortices or along flow lines, and others exhibit no relationship with anything nearby,” said Orton. “Some wave trains appear as if they are converging, and others appear to be overlapping, possibly at two different atmospheric levels. In one case, wave fronts appear to be radiating outward from the center of a cyclone.”


Although analysis is ongoing, most waves are expected to be atmospheric gravity waves – up-and-down ripples that form in the atmosphere above something that disturbs air flow, such as a thunderstorm updraft, disruptions of flow around other features, or from some other disturbance that JunoCam does not detect.



JUNO orbiting Jupiter. Animation Credit: NASA

The JunoCam instrument is uniquely qualified to make such a discovery. JunoCam is a color, visible-light camera which offers a wide-angle field of view designed to capture remarkable pictures of Jupiter’s poles and cloud tops. As Juno’s eyes, it helps provide context for the spacecraft’s other instruments. JunoCam was included on the spacecraft primarily for public engagement purposes, although its images also are helpful to the science team.


Juno launched on Aug. 5, 2011, from Cape Canaveral, Florida, and arrived in orbit around Jupiter on July 4, 2016. To date, it has completed 15 science passes over Jupiter. Juno’s 16th science pass will be on Oct. 29. During these flybys, Juno is probing beneath the obscuring cloud cover of Jupiter and studying its auroras to learn more about the planet’s origins, structure, atmosphere and magnetosphere.


JPL manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the Science Mission Directorate. Lockheed Martin Space Systems in Denver, Colorado, built the spacecraft. JPL is a division of Caltech in Pasadena, California.


More information on the Juno mission is available at:
https://www.nasa.gov/juno


https://www.missionjuno.swri.edu


The public can follow the mission on Facebook and Twitter at:


http://www.facebook.com/NASAJuno


http://www.twitter.com/NASAJuno


Image (mentioned), Animation (mentioned), Text, Credits: NASA/JoAnna Wendel/JPL/DC Agle/Southwest Research Institute/Deb Schmid.


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Battle of Largs Viking Monument, Largs, Ayrshire, Scotland, 24.10.18.Hard to believe that...








Battle of Largs Viking Monument, Largs, Ayrshire, Scotland, 24.10.18.


Hard to believe that it’s just over a month or so since I last visited here. Lot colder and bleaker today!


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Ilton Temple near Masham in Autumn Photoset 3, Yorkshire, 20.10.18.











Ilton Temple near Masham in Autumn Photoset 3, Yorkshire, 20.10.18.


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