суббота, 9 ноября 2019 г.

A Virtual Reality Camera Captures Life and Science Aboard the Space Station













ISS - International Space Station patch.

Nov. 5, 2019

Inside ISS at 360°. Image Credits: Courtesy of Felix & Paul Studios / Time

With only minutes until sunrise aboard the International Space Station (ISS), astronaut Nick Hague rushed to shut off the lights in the Japanese Experiment Module (JEM). Traveling 17,500 miles per hour, the space station orbits Earth 16 times in 24 hours, so every 90 minutes, the space station experiences a sunrise. For this sunrise, though, the speed of their approach was putting a time crunch on Hague. To capture this moment, timing was everything as he worked diligently to set up the perfect camera shot.

With moments to spare, the camera was ready, the module was dark, and Hague positioned at the window of the JEM. The first orange light shot into the orbiting laboratory. Within a minute, the module of the space station was bright again, this time from the natural light of the sun.


Animation above: NASA astronaut Nick Hague looks out the window in the Japanese Experiment Module (JEM) as the sun rises and the ISS Experience camera films the moment. Animation Credit: NASA.

Only a few humans ever get to experience this unique vantage point. The virtual reality (VR) project Hague was filming for, Space Explorers: The ISS Experience (ISS Experience), attempts to bring this perspective back to Earth for the rest of us.

Partnering with the ISS National Lab and Time Magazine, a team from Felix and Paul Studios launched a high quality 360 degree camera to space to help tell the story of science and life aboard the orbiting laboratory. The project, currently in the process of being filmed, serves as an outreach project as well a technology demonstration, testing the limits of filming in the harsh environment of space.

The idea for the project came about after the studio worked on episodes of a virtual reality series called Space Explorers that showed astronauts training on Earth.


Image above: A view of Canadian Space Agency (CSA) astronaut David Saint-Jacques setting up the Z-CAM V1 Pro Cinematic camera for the ISS Experience payload. The International Space Station Experience (ISS Experience) creates a virtual reality film documenting daily life aboard the space station. Image Credit: NASA.

“The natural next step was to actually take the viewer to space,” says Felix and Paul Studios co-founder and creative director Félix Lajeunesse. “We wanted to bring the viewer to the International Space Station to be alongside astronauts to experience the reality and challenges of life in microgravity and be part of the journey of learning to live and do science in space.”

That step required the team to start from scratch when it came to the camera. The studio had experience creating virtual reality films, but their typical camera was the size and shape of a four-foot-tall tree. That was not going to work in the tight confines of the space station. Instead, they collaborated with camera company Z-Cam to develop a new virtual reality camera system much smaller in size.

The resulting device launched on the 16th SpaceX commercial resupply services mission in December 2018 along with a number of other scientific experiments. Since then, the team has recorded many moments, including a jam session among the astronauts, crew meals and the arrival of new astronauts. The team is recording a few hours a week to document life in space. One of Felix and Paul’s primary concentrations is filming science on station.


Image above: A 360 image of the Cupola of the International Space Station taken as a part of the ISS Experience. Image Credits: Courtesy of Felix & Paul Studios / Time.

“Our focus has been thinking about and finding science experiments that when you see them, you're immersed in them,” says Lajeunesse. “Your mind can start spinning, thinking about what technologies are going to come next and how that research leads to a future path.”

The experiments filmed for ISS Experience so far include the SPHERES robots as they are flying around the station, as well as the growing and harvesting of vegetables.

“The science is ultimately the most important thing we are doing on the space station,” says Dylan Mathis, NASA’s communications manager for the International Space Station Program. “We are conducting science every day and it is science we can't do anywhere else. VR allows us to show people that in a different way.”


Animation above: NASA astronaut Drew Morgan sets up the ISS Experience camera for a recording session in the Cupola of the space station as Earth goes by through the window. Animation Credit: NASA.

The astronauts are the main subjects of the film, but since they are the sole residents of the space station, they are also the videographers behind the camera. That meant learning the basics of filming for virtual reality.

By the time each astronaut nears the end of their mission, most have become experts at setting up and using the camera, sometimes choosing to film moments on their own. This ease is what enabled Hague to capture the sunrise with only moments to spare.

So far, the footage coming back seems to be achieving the goal of immersing audiences in life aboard the space station. NASA astronaut Sunita Williams, who lived on the space station during Expedition 14/15 and Expedition 32/33, got the chance to watch some of the initial footage.

It was like I was back there in and on the International Space Station,” says Williams. “You forget you have [a VR headset] on your head, and you just keep looking around. It gives a huge appreciation to all that is inside the space station and how people live and work.”


Animation above: NASA astronaut Anne McClain works on setting up the ISS Experience camera aboard the International Space Station. Animation Credit: NASA.

While most of the filming has been completed, the biggest technical challenge is yet to come: capturing a spacewalk in virtual reality. This task requires an entirely new camera that Felix and Paul have been developing alongside their partner, Nanoracks. The team expects to launch the camera and begin production of spacewalk filming in 2020. Since they have no solid end dates for filming, the team has yet to announce a release date for the series.

The footage is being shot not only as entertainment and outreach but also as a test of virtual reality technologies as a means of documenting space travel and camera operations in space. Lajeunesse anticipates future spacecraft being equipped with virtual reality technology.


Image above: A 360 photo of NASA astronaut Anne McClain performing her daily training sessions. Daily exercise in space is crucial for astronauts to prevent muscle loss. Image Credits: Courtesy of Felix & Paul Studios / Time.

“I think it is inevitable that VR is going to be the default way to document space exploration moving forwards. It is a perfect match between medium and story,” he says. “Space exploration is something that you want to live. You want to be there. You want to experience it. Everything we're doing on station right now is a demonstration for the spaceflight industry and the entertainment industry of how we can use this medium moving forward in the space world.”

Related links:

ISS Experience: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7877

ISS National Lab: https://www.issnationallab.org/blog/experience-the-international-space-station-like-never-before/

Felix and Paul Studios: https://www.felixandpaul.com/?projects/intro

Time Magazine: https://time.com/space-explorers/

SPHERES: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=1760

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Animations (mentioned), Images (mentioned), Text, Credits: NASA/Carrie Gilder/JSC/International Space Station Program Science Office/Erin Winick.

Greetings, Orbiter.ch

* This article was originally published here

Rock Crystal Ball, Wigber Low Anglo-Saxon and Bronze Age Burial Grounds, Weston Park Museum,...

Rock Crystal Ball, Wigber Low Anglo-Saxon and Bronze Age Burial Grounds, Weston Park Museum, Sheffield, 20.10.19.

This unusual item of grave goods was found with the burial of a young woman and may have been a charm or amulet.



* This article was originally published here

A novel method for analyzing marine sediments contributes to paleoclimate reconstitution


The analysis of marine sediments has become a powerful research method in paleoclimatology. The composition of the sediments carried by rivers from the mainland to the ocean can be used as a basis for calculating variables such as temperature, precipitation and marine salinity. In the context of ongoing global climate change, the study of the past is fundamental to validating the accuracy of the climate models used to make predictions.

A novel method for analyzing marine sediments contributes to paleoclimate reconstitution
Storm over Campo de Sao Joao, Piaui State, where sediment samples for paleoclimate
research were collected [Credit: Vinicius Mendes]
A novel method of sediment analysis was proposed by Vinicius Ribau Mendes, a professor at the Federal University of Sao Paulo (UNIFESP), in Brazil, in an article published in Paleoceanography and Paleoclimatology, a journal of the American Geophysical Union (AGU). As a tribute to its originality, the study was also featured in the section “Research Spotlights” of EOS: Earth & Space Science News, another AGU publication.

The study was conducted during Mendes’s PhD research with the support of a scholarship from FAPESP and was supervised by Paulo Cesar Fonseca Giannini. The study also received funding via a Young Investigator Grant awarded to Cristiano Mazur Chiessi, a co-author of the article, and a research grant under FAPESP’s Multiuser Equipment Program awarded to Giannini.

Mendes and collaborators analyzed marine sediment cores collected off Brazil’s northeastern coast. A marine sediment core is a tubular sample of mud extracted from the sea bed to capture stratigraphic layers while preserving the depositional sequence; younger sediments are at the top, and older sediments are at the bottom.

The cores analyzed by the researchers contained clay minerals, quartz and feldspar transported from the continent by the Parnaiba, the most important river in the region. Feldspars, a group of aluminosilicate minerals containing calcium, sodium and potassium, make up more than half of the Earth's crust.


Any substantial change undergone by the river, such as variations in the rainfall regime, is potentially reflected by these sediments. “We propose a new method of reconstructing the changes that have occurred in continental precipitation during the past 30,000 years based on the luminescence of quartz and feldspar grains. This luminescence varies according to the geological constitution of the areas in which the crystals originated and the length of time they were exposed to surface processes before reaching the ocean bottom. A crystal from the headwaters of the river has a specific signature that differs from the signature of a crystal from the middle or lower reaches of the river. In the case of the Parnaiba, an increase in rainfall has a significant impact on its source, so a larger proportion of grains from this area in a marine sediment core reflects a rise in precipitation,” Mendes told Agencia FAPESP.

Luminescence is light emitted by materials that have been exposed to ionizing radiation and are subjected to a stimulus such as heat or light. Other studies have discovered that for quartz, the intensity of light emission or sensitivity depends on the geological medium in which the grain was formed and the duration of its exposure to sunlight during successive transportation events down the river until it reached the ocean. “We proved this empirically by collecting quartz and feldspar samples along the Parnaiba. We found significant differences between samples from the headwaters and from the lower reaches of the river,” Mendes said.

The physicochemical basis for these differences is not fully understood. Quartz is a simple material that is more abundant in sediments than feldspar. Quartz mainly consists of silica (silicon dioxide, SiO2) but may contain defects formed by the incorporation of chemical elements other than silicon and oxygen or due to the absence of these elements in the crystal lattice (“vacancies”). Luminescence results from these alterations in the lattice; the alterations depend on the chemical composition of the medium in which the rock was formed. Once formed and transformed into the sediment, the mineral is influenced by other factors, such as fragmentation, which changes the way it interacts with ionizing radiation in the environment, exposure to sunlight, and a high incidence of cosmic rays.

Exactly how these factors influence the capacity of defects to create luminescence is unknown, but a study conducted in the Amazon River basin by Andre Oliveira Sawakuchi, a professor at the University of Sao Paulo’s Institute of Geosciences (IGc-USP), and collaborators showed that the longer quartz remains exposed to terrestrial surface processes, the greater its luminescence.

“These physicochemical hypotheses about the differences are still being studied,” Mendes said. “We don’t have a definitive explanation. What we can say for sure, because we have the empirical data, is that crystals from various sites along the course of the river are different. So when we found grains of these crystals in marine sediment cores, we were able to measure their luminescence to determine where they were formed and map the process that took them from the continent to the ocean.”


Luminescence was measured in samples taken every 2 cm along the core. All samples were exposed to the same type and quantity of ionizing radiation and then stimulated by heat or light.

“Our novel method complements two others that are well established in the scientific literature. One produces precise and accurate information about rainfall and is based on measuring the proportion of hydrogen isotopes present in highly resistant molecules of terrestrial plants transported to the ocean. These isotopes, which the plants incorporate into their molecules, come from rainwater,” Mendes explained.

The stable isotopes of hydrogen are protium, with one proton and one electron, and deuterium (heavy hydrogen), with one proton, one neutron and one electron. Protium, the most abundant isotope, combines with oxygen to form ordinary water (H2O), and deuterium combines with oxygen to form heavy water (D2O).

Rainclouds in Brazil’s Northeast region travel from the ocean to the continent, so the more it rains, the less deuterium falls on the land because heavy water is denser and tends to fall first. The proportions of deuterium and protium in plants deposited at different depths of marine sediments therefore provide very precise information on variations in the amount of precipitation over time.

“Despite its precision, however, this method is very laborious and costly. It also depends on the preservation of the organic matter in the sediment, which isn’t always the case,” Mendes said.

The second method is based on analyses of the chemical composition of sediments using X-ray fluorescence. The technique entails exciting the sample with X-rays and analyzing the characteristics of the electromagnetic signal emitted in response. Each chemical element emits information in a specific frequency band, and the elements present in the sample can be identified based on this information. The goal is to determine the proportions of titanium and iron, which are continental elements, and that of calcium, which is from the shells of marine animals. Increases in the percentages of titanium and iron indicate that more material was transported from the land into the ocean due to more intense rainfall in a given period compared to the conditions in previous periods.


This second method is simple, fast and inexpensive. Although determining the percentages of hydrogen isotopes takes several months of analysis in a laboratory, samples can be scanned for titanium, iron and calcium in a day. The problem is a lack of precision compared with the first method. Variations in the percentages of titanium and iron indicate an increase or decrease in precipitation in a given period, but the variations are not proportional to the amount of rainfall because they are also affected by rising and falling sea levels. If the sea level falls, the mouth of the river moves closer to the area from which the sediment is collected. If the sea rises, the distance to the river mouth increases. In this case, any increase or decrease in the proportions of titanium and iron in the sediment core may not be caused by rain variations. Thus, the lack of precision of this method offsets its advantages in terms of speed and cost.

“Our new method lies somewhere between the two,” Mendes said. “It is less precise than the first and more precise than the second. It is also intermediate in terms of difficulty and cost. Additionally, quartz is a highly resistant material, so there is no risk it will degrade in the sediment, as can happen with organic molecules in the first method. Because the new method is based on the intrinsic properties of these crystals, there is also no risk they will be affected by external factors such as rising sea levels, as there is with the second method. We do not propose substitution of one method for another. They’re complementary and should be used as appropriate in each case.”

The researchers are also assessing the possibility of constructing a luminescence scanner for marine sediment cores.

“The equipment used to measure luminescence sensitivity is sophisticated, but the laboratory procedure involved is relatively simple and fast, and the targeted minerals are more common in sediments coming from the continent. The method developed by Vinicius Mendes therefore promises to become routine from now on in the study of paleoprecipitation based on marine sediments in the areas of influence of major rivers,” Giannini said.

Source: Fundacao de Amparo a Pesquisa do Estado de Sao Paulo [November 06, 2019]



* This article was originally published here

2019 November 4 Near the Center of the Lagoon Nebula Image...



2019 November 4

Near the Center of the Lagoon Nebula
Image Credit & Copyright: Zhuoqun Wu, Chilescope

Explanation: Stars are battling gas and dust in the Lagoon Nebula but the photographers are winning. Also known as M8, this photogenic nebula is visible even without binoculars towards the constellation of the Archer (Sagittarius). The energetic processes of star formation create not only the colors but the chaos. The glowing gas results from high-energy starlight striking interstellar hydrogen gas and trace amounts of sulfur, and oxygen gases. The dark dust filaments that lace M8 were created in the atmospheres of cool giant stars and in the debris from supernovae explosions. The light from M8 we see today left about 5,000 years ago. Light takes about 50 years to cross this section of M8.

∞ Source: apod.nasa.gov/apod/ap191104.html

Faience Bead and Flint Arrowhead, Bronze Age Burial near Doll Tor Stone Circle, Derbyshire, Weston...

Faience Bead and Flint Arrowhead, Bronze Age Burial near Doll Tor Stone Circle, Derbyshire, Weston Park Museum, Sheffield, 20.10.19.



* This article was originally published here

Jovian Vortex View













NASA - JUNO Mission logo.

Nov. 9, 2019


NASA’s Juno spacecraft captured this stunningly detailed look at a cyclonic storm in Jupiter’s atmosphere during its 23rd close flyby of the planet (also referred to as “perijove 23”).

Juno observed this vortex in a region of Jupiter called the “north north north north temperate belt,” or NNNNTB, one of the gas giant planet’s many persistent cloud bands. These bands are formed by the prevailing winds at different latitudes. The vortex seen here is roughly 1,200 miles (2,000 kilometers) wide.

Jupiter is composed mostly of hydrogen and helium, but some of the color in its clouds may come from plumes of sulfur and phosphorus-containing gases rising from the planet's warmer interior.

Citizen scientist Kevin M. Gill created this image using data from the spacecraft's JunoCam imager. It was taken on Nov. 3, 2019, at 2:08 p.m. PST (5:08 p.m. EST). At the time, the spacecraft was about 5,300 miles (8,500 kilometers) from Jupiter’s cloud tops above a latitude of about 49 degrees. ​

Juno spacecraft orbiting Jupiter

JunoCam's raw images are available for the public to peruse and process into image products at https://missionjuno.swri.edu/junocam/processing.   

More information about Juno is at https://www.nasa.gov/juno and https://missionjuno.swri.edu.

Image credit: Image data: NASA/JPL-Caltech/SwRI/MSSS/Image processing by Kevin M. Gill, © CC BY/Animation Credit: NASA/Text Credits: NASA/Tony Greicius.

Greetings, Orbiter.ch

* This article was originally published here

Stave churches in Norway older than thought


What's the real age of Norwegian stave churches? The usual method for dating wood is to measure the variation in the width of the tree rings and compare them to already dated samples.

Stave churches in Norway older than thought
Hopperstad Stave Church in Sogn og Fjordane county is dendro-dated to 1131-1132. Previously,
the date was estimated at 1125-1250 [Credit: Jan Michael Stornes]
Recently, researchers have used a different measurement method called photodendrometry. With this technique, the material can be photographed in place. The method has the advantage of not needing to take core samples, and scientists can photograph large amounts of material in a protected building and procure larger amounts of data. This provides more precise knowledge of the estimated construction date, because it allows wood that cannot be core sampled to also be dated.

Through the Stave Church Preservation program headed by the Norwegian Directorate for Cultural Heritage, dendrochronologists at NTNU received money to study the country's stave churches more closely. The program has yielded results.

"We now know the age of some stave churches almost to the year," says Terje Thun. He is an associate professor at the NTNU University Museum in Trondheim. Thun is one of the country's foremost experts in dendrochronology, or tree ring dating.

Photodendrometry less invasive

Thun explains that the original dating method of measuring tree rings with a magnifying glass has some limitations. If tree rings cannot be measured on the surface or end of a plank or log, then researchers need core samples. This is not always possible—or desirable.


During the stave church program, photodendrometry was tested as a non-destructive method. The researchers photographed the wall boards in various churches, and did the actual measuring of the tree rings in the laboratory with the photos.

"In this way, researchers were able to examine all parts of the stave churches without any invasive techniques," Thun said.

Urnes Stave Church older than assumed

Over a long research career, Thun has studied wood samples from stave churches in order to more accurately pinpoint Norway's most important contribution to world architecture.

Stave churches in Norway older than thought
Photo from Urnes Stave Church, taken while photographing tree rings in the church choir
[Credit: Jan Michael Stornes]
The stave church preservation program, which lasted until 2016, accelerated that research. Thun and his staff were able to conduct more systematic analyses of various building sections in several of the churches.

"Urnes Stave Church was especially thoroughly studied, since it's considered to be the oldest stave church in Norway," says Thun.

He and several of his colleagues and researchers in Norway and Denmark can now confirm that several of the churches are older than many historians previously believed.

Dendrodating indicates that part of Urnes Stave Church, which was estimated built before 1100, was constructed using timber from 1069 and 1070. The slightly younger part of Urnes is dated to 1129-1130.

For the sake of clarity: dendrochronology can date the year a tree was felled for the stave churches. The likelihood is that the felling year was also when the construction began.

Several stave churches older than presumed

According to Thun, Urnes Stave Church is interesting in several ways.

Already in the 1950s, archaeological excavations were being carried out to learn more about this special church at the head of the Sognefjord. Norway's oldest stave church is also on the UNESCO World Heritage list, and many books have been written about the unique church building.


"Research has been done on the stave churches in the past, too, but not as systematically as under the stave church program. Over the years, dating estimates were based on construction technique and style and spanned almost a hundred years.

"Now we're sure of the age, and several of our stave churches are older than first thought," Thun says.

Stave churches in Norway older than thought
Using a method called photodendrometry, researchers can reduce the number of core samples they need to take for
dating wooden buildings. They can now get enough information from photographs, which yields more data
and more precise information. Pictured: Thomas Bartholin (at left) and Jan Michael Stornes
[Credit: Leif Anker]
Researchers thoroughly examined the stave churches in Kaupanger, Hoppestad and Urnes using photodendrometry. Some parts of the Gol and Borgund stave churches were also documented using the same method.

The work of dating the stave churches has also given the researchers knowledge of building practices and material choices.

"Among other things, we can now study what kinds of forests were available at different periods," Thun says.

The preparatory work of the stave church program showed that many of the churches had serious construction problems and required a great deal of maintenance. So building historians, art historians, conservators, archaeologists, craftsmen and other professional groups were all involved in the project.

Dendrochronology method can tell us about climate

Thun's colleague, researcher Helene Lovstrand Svarva, also participated in the stave church program.

They both work at The National Laboratory for Age Determination that is part of the NTNU University Museum in Trondheim.

Svarva is particularly concerned with how climate can be studied using dendrochronology.

"Dendroclimatology is a major field of study, and here in Northern Europe we can use the trees' response to summer temperatures to find out more about climate variations over time," she says.


According to the researcher, the tree-ring chronology of the stave churches covers a climatically interesting period, which is often called the Medieval Climate Anomaly. This was a period that was assumed to be warmer than the periods before and after.

By comparing summer temperatures over time, Svarva can find out how the climate has changed throughout history.

"Long chronologies allow us to see variations over time that can give us a picture of how temperatures have changed. It's especially interesting to find out how today's climate can be seen in light of the climate almost a thousand years ago," she says.

But, Svarva points out, "trees are also affected by forces other than temperature, so we need a lot of trees as a source. We also need chronologies from many parts of the world to create a picture of how temperature has changed in time and space."

Authors: Nina Tveter & Kjersti Lunden Nilsen | Source: Norwegian University of Science and Technology [November 06, 2019]



* This article was originally published here

European Log Boat (circa 456CE), McManus Museum and Gallery, Dundee, 24.10.19.

European Log Boat (circa 456CE), McManus Museum and Gallery, Dundee, 24.10.19.



* This article was originally published here

NASA’s TESS Presents Panorama of Southern Sky













NASA - TESS Mission logo.

Nov. 5, 2019


Image above: The plane of our Milky Way galaxy arcs across a starry landscape in this detail of the TESS southern sky mosaic. Image Credits: NASA/MIT/TESS and Ethan Kruse (USRA).

The glow of the Milky Way — our galaxy seen edgewise — arcs across a sea of stars in a new mosaic of the southern sky produced from a year of observations by NASA’s Transiting Exoplanet Survey Satellite (TESS). Constructed from 208 TESS images taken during the mission’s first year of science operations, completed on July 18, the southern panorama reveals both the beauty of the cosmic landscape and the reach of TESS’s cameras.

“Analysis of TESS data focuses on individual stars and planets one at a time, but I wanted to step back and highlight everything at once, really emphasizing the spectacular view TESS gives us of the entire sky,” said Ethan Kruse, a NASA Postdoctoral Program Fellow who assembled the mosaic at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

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New human ancestor discovered in Europe


Our upright posture may have originated in a common ancestor of humans and great apes who lived in Europe - and not in Africa, as previously thought. That’s the conclusion reached by an international research team headed by Professor Madelaine Bohme from the Senckenberg Center for Human Evolution and Palaeoenvironment at the University of Tubingen in a study published Wednesday in the journal Nature and the Journal of Human Evolution. Bohme has discovered fossils of a previously unknown primate in southern Germany. The fossils of Danuvius guggenmosi, which lived 11.62 million years ago, suggest that it was well adapted to both walking upright on two legs as well as using all four limbs while climbing. The ability to walk upright is considered a key characteristic of humans.

New human ancestor discovered in Europe
A male Danuvius guggenmosi probably looked something like this
[Credit: Universitat Tubingen]


The researchers say their analysis of the fossils show that Danuvius were able to walk on two legs nearly twelve million years ago. Up to now, the oldest evidence of an upright gait is a mere six million years old, and was found on the Mediterranean island of Crete as well as in Kenya.

New human ancestor discovered in Europe
On the basis of the fossils, the team reconstructed other bones
[Credit: Universitat Tubingen]
“The finds in southern Germany are a milestone in palaeoanthropology, because they raise fundamental questions about our previous understanding of the evolution of the great apes and humans,” says Bohme. Working with the Professor from Tubingen were researchers from Bulgaria, Germany, Canada and the United States.

New human ancestor discovered in Europe
The 21 bones of the most complete partial skeleton of a male Danuvius
[Credit: Universitat Tubingen]
Ever since Darwin, the early evolution of humans and our cousins, the great apes, has been intensely debated. At the center of these debates is the question of how humans came to walk on two legs. Did bipedal humans evolve from tree-dwelling, monkey-like apes which moved on all fours? From brachiating apes similar to orangutans?  Or from knuckle-walking apes like chimpanzees and gorillas? Over the last 150 years many hypotheses have been advocated, but supporting fossil evidence has so far mostly been lacking.

New human ancestor discovered in Europe
Part of the reconstructed skeleton
[Credit: Universitat Tubingen]


The Danuvius guggenmosi fossils were discovered between 2015 and 2018. Working in the Hammerschmiede clay pit in the Allgau region of Bavaria, Bohme and her team excavated more than 15,000 fossil vertebrate bones from the ancient humid and forested ecosystems that were abundant in southern Germany at that time. The new primate fossils include the remains of at least four individuals.

New human ancestor discovered in Europe
Bones from the hand of a male Danuvius
[Credit: Universitat Tubingen]
The most complete skeleton, of a male Danuvius, has body proportions similar to modern-day bonobos. Thanks to completely preserved limb bones, vertebra, finger and toe bones, the researchers were able to reconstruct the way Danuvius moved about in its environment. “For the first time, we were able to investigate several functionally important joints, including the elbow, hip, knee and ankle, in a single fossil skeleton of this age,” Bohme says. “It was astonishing for us to realize how similar certain bones are to humans, as opposed to great apes.”

New human ancestor discovered in Europe
Reconstruction (white bones) of the skull and lower jaw
[Credit: Universitat Tubingen]
The team’s findings indicate that Danuvius could walk on two legs and could also climb like an ape. The spine, with its S-shaped curve, held the body upright when standing on two legs. The animal’s build, posture, and the ways in which it moved are unique among primates. “Danuvius combines the hindlimb-dominated bipedality of humans with the forelimb-dominated climbing typical of living apes,” says Professor David Begun, a researcher from the University of Toronto.

New human ancestor discovered in Europe
Two chest vertebrae of a male Danuvius
[Credit: Universitat Tubingen]


These results suggest that human bipedality evolved in arboreal context over 12 million years ago. “In contrast to later hominins, Danuvius had a powerful, opposable big toe, which enabled it to grasp large and small branches securely,” says Professor Nikolai Spassov of the Bulgarian Academy of Science.

New human ancestor discovered in Europe
The big toe of a male Danuvius (white bones reconstructed)
[Credit: Universitat Tubingen]
Danuvius was about one meter in height. Females weighed about 18 kg, less than any great ape alive today. The male would have tipped the scales at about 31 kg, also at the low extreme of modern great ape body size. The ribcage was broad and flat, and the lower back was elongated; this helped to position the center of gravity over extended hips, knees and flat feet, as in bipeds. Several key-features of human bipedality have been found on bones from the leg.

New human ancestor discovered in Europe
Bones from the hand of a male Danuvius
[Credit: Universitat Tubingen]
These results received support from a recent independent study of a 10 million-year-old ape hip-bone found in Hungary. “That fossil also indicates that the European ancestors of African apes and humans differed from living gorillas and chimpanzees,” says David Begun, who was also involved in the study of the Hungarian fossil. The researchers point out that the ancestors we share with living African apes were as unique as we are today. “This newly identified pattern of positional behavior helps us to understand the starting point from which African apes and humans diverged,” he said, underlining the team’s basic premise.

Source: Universitat Tubingen [November 06, 2019]



* This article was originally published here

2019 November 9 Saturn the Giant Image Credit:...



2019 November 9

Saturn the Giant
Image Credit: NASA

Explanation: On May 25, 1961 U.S. president John Kennedy announced the goal of landing astronauts on the Moon by the end of the decade. By November 9, 1967 this Saturn V rocket was ready for launch and the first full test of its capabilities on the Apollo 4 mission. Its development directed by rocket pioneer Wernher Von Braun, the three stage Saturn V stood over 36 stories tall. It had a cluster of five first stage engines fueled by liquid oxygen and kerosene which together were capable of producing 7.9 million pounds of thrust. Giant Saturn V rockets ultimately hurled nine Apollo missions to the Moon and back again with six landing on the lunar surface. The first landing mission, Apollo 11, achieved Kennedy’s goal on July 20, 1969.

∞ Source: apod.nasa.gov/apod/ap191109.html

Watch Mercury Travel Across the Face of the Sun Monday














Astronomy.

November 8, 2019

A Transit of Mercury Happens Nov. 11

Artist's view of Mercury transit

The sky will put on a show Nov. 11 when Mercury journeys across the Sun. The event, known as a transit, occurs when Mercury passes directly between Earth and the Sun. From our perspective on Earth, Mercury will look like a tiny black dot gliding across the Sun’s face. This only happens about 13 times a century, so it’s a rare event that skywatchers won’t want to miss! Mercury’s last transit was in 2016.  The next won’t happen again until 2032!

“Viewing transits and eclipses provide opportunities to engage the public, to encourage one and all to experience the wonders of the universe and to appreciate how precisely science and mathematics can predict celestial events,” said Mitzi Adams, a solar scientist in the Heliophysics and Planetary Science Branch at NASA’s Marshall Space Flight Center in Huntsville, Alabama. “Of course, safely viewing the Sun is one of my favorite things to do.”

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Monifieth Pictish Cross Slab 2 Recreation by Artist David McGovern, McManus Museum and Gallery,...

Monifieth Pictish Cross Slab 2 Recreation by Artist David McGovern, McManus Museum and Gallery, Dundee, 24.10.19.



* This article was originally published here

Mammals' complex spines are linked to high metabolisms; we're learning how they evolved


Mammals' backbones are weird. Compared to other four-legged animals like reptiles, mammal spines are a complex mix of sections of differently-shaped bones. Our Frankenstein's monster backbones are a key component of mammals evolving the ability to move in a bunch of different ways--compare a cheetah running, a person walking, a bat flying, and a whale swimming. A new study in Nature Communications delves into the nitty-gritty of how mammals' backbones became so complex. The scientists discovered that the process was marked by big, dramatic evolutionary changes, and that it's linked to mammals being active animals with high metabolisms.

Mammals' complex spines are linked to high metabolisms; we're learning how they evolved
Early mammal relative, Ophiacodon, whose still has a relatively simple, uniform backbone
[Credit: Field Museum]
"Looking around, the animals and plants that surround us are remarkably complex, but putting a number to that phenomenon is very tricky. With this study, we wanted to take a complex system-the mammal vertebral column-and measure how its complexity changed through time. We show that increases in complexity were discrete steps like rungs on a ladder instead of a smooth increase like a ramp. Adaptations for high activity levels in mammals seem to trigger these jumps in complexity, and they continue to influence its evolution today," says Katrina Jones, the paper's first author and a paleontologist from Harvard's Museum of Comparative Zoology.

"It's basically the story of how weird mammals' backbones are and how they evolved to be like that, starting starting from ancient relatives whose spines were much simpler," says Ken Angielczyk, a paleontologist at the Field Museum and one of the study's authors. "It looks like it's not just a gradual accumulation of little changes over time--it's more discrete changes. And one of these big changes may be related to changes in how mammals are able to move and breathe that let us be so active."


Angielczyk and his co-authors, Jones and Stephanie Pierce of Harvard's Museum of Comparative Zoology, wanted to figure out how and when mammals and their ancestors first evolved these specialized backbones. They examined fossil backbones from mammal relatives called synapsids that lived between 300 and 200 million years ago and took precise measurements of the bones to determine how the spines were changing over time. They then fed all the data into a computer program that modeled the different ways that the spines might have evolved.

Based on the information from all the fossils, the model showed that the changes in synapsid backbones probably developed in comparatively quick bursts, rather than a super-slow, gradual pathway. Of course, explains Angielczyk, evolution is such a slow process that even quick bursts of evolutionary change can take millions of years. "It looks fast from our mountain-top view of evolution, but if you were one of these animals, it's not like your grandchildren would look totally different from you," he says. Rather, these big leaps really just mean that the evolutionary changes happened more quickly than what you'd expect to see in a totally random system where mutations and changes weren't good or bad, just neutral. Basically, big step-wise jumps in evolution mean that the changes that were happening made a big difference in the organisms' lives, making them better able to survive and pass on their genes.

Mammals' complex spines are linked to high metabolisms; we're learning how they evolved
A modern dog skeleton, which has a complex backbone made up of different sections
[Credit: Field Museum]
Increasingly complex spines were such a good thing for mammal ancestors, the researchers argue, because they were part of a suite of changes related to higher activity levels.

Compared to reptiles, modern mammals have very high metabolisms--we have more chemical reactions happening to keep our bodies going--and we're more active. In general, mammals can move more efficiently and have more stamina, but those benefits come with a cost: mammals have to breathe more than reptiles do, we have to eat more, and we need fur to keep our bodies warm enough to keep our systems going. "As part of our study, we found that modern mammals with the most complex backbones also usually have the highest activity levels," says Pierce, "and some changes in in backbone complexity evolved at about the same time that other features associated with a more active lifestyle evolved, like fur or specialized muscles for breathing."


"The uniqueness of mammalian backbones is something that's been recognized for a long time, and our results show that there's a strong connection between the evolution of our backbones and the evolution of the soft tissues in our muscular and respiratory systems," says Angielczyk.

"We're interested in the big picture of how backbones evolve, and there are these long-standing ideas about it being related to the evolution of mammals' respiration, locomotion, and high acitvity levels," Angielczyk adds. "We're trying to test and refine those hypotheses, and to use them to better understand the broader question of how complexity increases through evolution."

And this big picture of how mammals' spines became complex could help to explain a lot about mammals alive today, including us. "Mammals kind of do their own thing," says Angielczyk. "If you look at mammals today, we have lots of weird features in our metabolism and our bodies and reproductive strategies. It would be really confusing to figure out how they evolved if you were only looking at modern mammals. But we have a really good fossil record of early mammal relatives, and that can help us understand the history of many of these very unusual traits."

"This study helps us answer an age-old question - how did life become so complex?" says Jones. By looking at this example system, we show that discreet changes, when added up over the millennia, can produce what seems at first glance to be a long-term trend. The evolution of complexity is, dare I say it, complex!"

Source: Field Museum [November 07, 2019]



* This article was originally published here

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