пятница, 15 ноября 2019 г.

Last Arctic ice refuge is disappearing


The oldest and thickest Arctic sea ice is disappearing twice as fast as ice in the rest of the Arctic Ocean, according to new research.

Last Arctic ice refuge is disappearing
New research finds the Arctic’s oldest and thickest ice is more mobile and is vanishing
twice as fast as ice in the rest of the Arctic [Credit: NOAA]
A new study in AGU's journal Geophysical Research Letters finds ice in the Arctic Ocean north of Greenland is more mobile than previously thought, as ocean currents and atmospheric winds are likely transporting the old, thick ice found there to other parts of the Arctic. As a result, ice mass in the area - the last place researchers think will lose its year-round ice cover - is declining twice as fast as ice in the rest of the Arctic, according to the new findings.

Climate models predict Arctic summers will soon be ice-free - perhaps as early as 2030 - meaning less than 1 million square kilometers (386,000 square miles) of summer sea ice will blanket the Arctic Ocean. Arctic warming has already created an environment which leads to younger sea ice. Watch a visualization of the age of Arctic sea ice over time here.


Most ice covering the Arctic is only one to four years old, according to the National Snow and Ice Data Center. As thin, young ice melts in future summers, only a 2,000-kilometer (1,240-mile) arc of ice will remain, stretching from the western Canadian Arctic Archipelago to Greenland's northern coast. In this slice of the Arctic, which experts call the Last Ice Area, sea ice is more than five years old and can measure more than four meters (13 feet) thick.

The new research suggests the Last Ice Area is a dynamic place encompassing two sub-regions where ice thickness fluctuates by 1.2 meters (4 feet) from year to year. Ice is becoming thinner in two distinct subregions, which are losing 0.4 meters (1.3 feet) of ice thickness per decade, amounting to a 1.5-meter (5 foot) loss of ice since the late 1970s, according to the new study.

Last Arctic ice refuge is disappearing
Annual mean sea ice thickness (m) over the Arctic Ocean from 1979 – 2018. The black line
 surrounds the area where the ice thickness exceeds 3 m and can be considered as the
 region known as the Last Ice Area. The white lines surround the two areas where
the ice thickness exceeds 4m [Credit: Kent Moore/University of Toronto]
"We can't treat the Last Ice Area as a monolithic area of ice which is going to last a long time," said Kent Moore, an atmospheric physicist at the University of Toronto in Canada and lead author of the new study. "There's actually lots of regional variability."

For wildlife who rely on sea ice for survival, the Last Ice Area offers a sanctuary, and is the final place they can retreat to in a warming world. Understanding how the Last Ice Area changes throughout the year could help pinpoint which spots are best suited to provide a refuge for wildlife who are dependent on sea ice, according to the study's authors.


Places with less ice movement, for example, may provide more suitable conditions for a wildlife sanctuary, as the ice will remain longer. The new study presents context for policymakers to consider when they establish protected areas in the Arctic, Moore said.

"Eventually the Last Ice Area will be the region that will repopulate the Arctic with wildlife," Moore said. "If we lose all the ice, we lose those species. This area will be a refuge where species can survive and hopefully expand their regions once the ice starts returning."

A dynamic zone

The Last Ice Area is home to the Arctic's oldest and thickest ice because ocean currents and atmospheric winds carry patches of floating ice in a circular pattern. These blocks of ice crash into each other and pile up along the northern edges of Greenland and Canada. Researchers, however, know little about how ice in this region moves and melts during the year.


This lack of knowledge prompted Moore and his colleagues to track changes in the Last Ice Area. In the new study, the team modeled sea ice cover, thickness and motion across the zone from 1979 to 2018. Their model, based on satellite observations and atmospheric data, revealed two regions with distinct seasonal and inter-annual fluctuations - one to the east and one to the west.

In both regions, sea ice was thinner and covered less area in the summer and early fall than in the Arctic winter, though ice thickness in the west tended to hit its minimum earlier in the season. Ice motion in the eastern portion of the Last Ice Area appeared to be more stable. Western ice - controlled by winds blowing clockwise - has begun moving faster, which could be the result of thinning ice.

According to Moore, the loss of ice in the Last Ice Area is likely due to ice movement out of the region, particularly in the west. If sea ice is thinner and moving faster, pieces at the margins will flow first into the open ocean, followed by larger bits from the center, like a big traffic jam.

"Historically, we thought of this place as an area that just receives ice," said David Barber, an Arctic climatologist from the University of Manitoba in Canada who was not involved in the new study. "But these results are teaching us that this is a dynamic area."

Source: American Geophysical Union [November 12, 2019]



* This article was originally published here

Ancient rain gauge: New evidence links groundwater, climate changes in deep time


Changes in groundwater millions of years ago created alternating layers of vivid yellow and brown in the mineral sphalerite, and those variations align with movements in Earth's orbit that impacted climate in the deep past, Penn State scientists found.

Ancient rain gauge: New evidence links groundwater, climate changes in deep time
Yellow and brown banding in the mineral sphalerite are caused by changes in rainfall and groundwater.
Penn State scientists found patterns in the banding match movement in Earth's orbit
that impacted climate in the deep past [Credit: Mingsong Li]
The findings provide new evidence for how changes in climate influenced the planet's rainfall and groundwater, a process that scientists have not well documented, the researchers said.

"This study shows sphalerite banding can be used as a fingerprint of groundwater in the geological past," said Mingsong Li, assistant research professor of geosciences at Penn State. "Groundwater is crucial for understanding global sea level change, chemical weathering and landscape evolution, and this study presents a new idea to help discern the role of groundwater in the Earth system."

Increased precipitation influenced the colored banding in sphalerite samples from the Upper Mississippi Valley Ore Mineral District in the U.S. Midwest, the scientists said. More rainfall lead to oxygen-rich groundwater flowing to depths where the mineral formed, and the increased oxidation resulted in lighter yellow bands. Drier times yielded darker brown colors.


Using new dating technology, the scientists found these deposition patterns corresponded with changes in Earth's orbit over tens of thousands to hundreds of thousands of years, known as Milankovitch astronomical cycles.

These cycles refer to changes in the shape of Earth's orbit and variations in the tilt of its rotation that may have led to warmer, wetter conditions for periods from 299 million to 252 million years ago, when the sphalerite formed, the scientists said.

"What we are doing is marrying geochemical research on ores with what we know about astronomical cycles from very different research," said Hubert Barnes, distinguished professor emeritus at Penn State. "No one has ever made an attempt at this before."


The research builds on previous work that shows hydrothermal fluids that created ore deposits in modern day Iowa, Illinois and Wisconsin started as groundwater in the Appalachian Mountains. The water was heated by geothermal processes and picked up metals and solutes along it journey.

But during times of high precipitation, new sources of groundwater flowed to roughly 3,000 feet below the surface carrying higher oxygen levels and mixing with the hydrothermal fluids to create different colored bands in the sphalerite.

The researchers digitized a grayscale profile of the sphalerite from Wisconsin and analyzed the bands using new computer software that can detect periodic signals in the samples. They found distinct frequency peaks in the banding that correlate with the Milankovitch cycles.


The results - published in the journal Geochemical Perspective Letters - could help explain changes in sea level during times in Earth's history when the planet was too warm for ice, the scientists said.

Changes in groundwater can have real impacts on sea level. If all groundwater drained into oceans today, sea level would rise more than 180 feet, according to the scientists.

Yet projections of long-term global mean sea level on times scales of hundreds to thousands of years often do not include the contributions of land water storage, the scientists said. The Intergovernmental Panel on Climate Change, for instance, considers water storage on land contribution to sea level rise to be small.

"This research opens a new way to evaluate climate control on groundwater activities linked to global water cycles," Li said. "This is the first direct evidence to show groundwater activities in the deep past."

Author: Matthew Carroll | Source: Pennsylvania State University [November 12, 2019]



* This article was originally published here

First All-Woman Spacewalk

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NASA astronauts and best friends, Christina Koch and Jessica Meir, made history Friday, October 18, 2019, by conducting the first all-woman spacewalk outside the International Space Station (ISS)! The Expedition 61 flight engineers ventured into the vacuum of space at 7:38 a.m. EDT to swap out a failed power controller that regulates the batteries used to collect and distribute power to the orbital laboratory – a task that took a total of seven hours and 17 minutes to complete.

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This was Koch’s fourth spacewalk and Meir’s first. Both women, selected as astronaut candidates in 2013, are on their first trip to work and live aboard the space station. Meir will be the 15th woman to spacewalk, and the 14th U.S. woman.

Get to know the astronauts

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In addition to being an astronaut, Christina Koch is an engineer and physicist. Her career has taken her to extreme parts of the planet to conduct scientific field missions in places like the Antarctic South Pole and Greenland’s Summit Station. Prior to being selected as an astronaut candidate in 2013, she worked as an Electrical Engineer at our Goddard Space Flight Center’s Laboratory for High Energy Astrophysics.

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Koch left Earth on March 14, 2019, and is slated to set a record for the longest single spaceflight by a woman with an expected total of 328 days in space. Her extended mission will provide researchers the opportunity to observe the effects of long-duration spaceflight on a female body in preparation for human missions to the Moon and Mars.

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Jessica Meir dreamed of the day she would make it to space since the age of five. That dream became a reality on Wednesday, Sept. 25, 2019 as she left Earth on her first spaceflight – later floating into her new home aboard the International Space Station.

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While Meir’s new home is more than 200 miles over the Earth, she is no stranger to extreme environments. She studied penguins in Antarctica and mapped caves in Italy  –  both of which prepared her for the ultimate extreme environment: space.

#AllWomanSpacewalk, what’s the deal?

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The all-woman spacewalk wasn’t something we purposefully planned; it is a testament to the increasing number of female astronauts in the space program. For example, Koch’s and Meir’s 2013 class of astronaut candidates was 50 percent women!

When asked in an interview about the importance of conducting her mission and this spacewalk, Koch said,  

“In the end, I do think it’s important, and I think it’s important because of the historical nature of what we’re doing. In the past women haven’t always been at the table. It’s wonderful to be contributing to the space program at a time when all contributions are being accepted, when everyone has a role. That can lead in turn to increased chance for success. There are a lot of people who derive motivation from inspiring stories of people who look like them, and I think it’s an important story to tell.” 

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It’s important to note that spacewalks are not easy; astronauts typically describe them as the most physically challenging thing they do. Assignments are made on the basis of which astronauts are the best prepared to accomplish the tasks at hand under the conditions at the time. Today, Koch and Meir were the top astronauts for the job.

Women are no stranger to spacewalks!

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While this was the first spacewalk to be conducted entirely by women, women are no strangers to spacewalks. Exactly 35 years and one week ago, Kathryn Sullivan (pictured above) made her own historic debut as the first U.S. woman to conduct a spacewalk. Since then, a total of 14 women (15 including Jessica) have ventured into the vacuum of space on 40 different spacewalks. Former Astronaut Peggy Whitson performed a record number of 10! From Astronauts to mission directors, women have been making their mark at the agency for decades now. A few of our recent pioneers are:

  1. Astronaut Kate Rubins: First person to sequence DNA in space
  2. Astronaut Peggy Whitson: First woman to command the ISS
  3. Sandra Cauffman: Director of our Earth Science’s Division
  4. Nicola Fox: Director of our Heliophysics Division
  5. Lori Glaze: Director of our Planetary Science Division

Coming soon: The first woman to walk on the Moon

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The first all-woman spacewalk is a milestone worth noting and celebrating as we look forward to putting the first woman and the next man on the Moon by 2024 with our Artemis lunar exploration program. With today’s historic event, we once again set a precedence for women to lead in space exploration.

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We hope achievements such as this provide inspiration to you all around the world, proving that hard work can lead you to great heights. This is not just a historic day for NASA, but a moment we can all feel proud of.

Didn’t have time to tune in? Check out the replay, here. Koch was wearing the spacesuit with red stripes, while Meir’s had no stripes.

If you’d like to keep up with Christian Koch and Jessica Meir’s work 254 miles above planet Earth, follow them on Twitter at @Astro_ Christina and @Astro_Jessica

Be sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Geoscientists reconstruct the climate of the past by analysing dripstones


In the last interglacial period on Earth about 125,000 years ago, the Indian monsoon was longer, more extreme and less reliable than it is today. This is the conclusion drawn by geoscientists from Ruhr-Universitat Bochum (RUB) and the University of Oxford, together with other colleagues from the UK, New Zealand, China and the USA. The team analysed a dripstone from a cave in north-eastern India, combining various methods that provide information about supra-regional and local weather phenomena and the climate dynamics of the past.

Geoscientists reconstruct the climate of the past by analysing dripstones
Five centimetres of this dripstone sample contain 40,000 years of climate history
[Credit: RUB, Marquard]
The team headed by Matthias Magiera, Dr. Franziska Lechleitner, Professor Ola Kwiecien and Dr. Sebastian Breitenbach describe the results in the journal Geophysical Research Letters.

Last and next interglacial period

"The last interglacial period is often considered an analogy to the expected climate changes," says Ola Kwiecien from the RUB Institute of Geology, Mineralogy and Geophysics. "Even though the factors that led to the warming were different then than they are today, of course." Findings about weather and climate phenomena from the last interglacial period provide researchers with clues as to how the climate might change as the earth warms up.

Geoscientists reconstruct the climate of the past by analysing dripstones
Just like a tree has annual rings, a dripstone has a lamination that develops over time when the
dripstone grows under different environmental conditions [Credit: RUB, Marquard]


The team analysed a dripstone from the Mawmluh Cave in north-eastern India. For one, the researchers determined so-called delta-18-O values, which are a measure of the strength of the Indian monsoon. In the process, they compared the ratio of heavy and light oxygen in the dripstone; this depends on the one hand on the source area of the monsoon, but also on the seasonal distribution of rainfall, temperature and intensity of precipitation. These factors play an important role for the strength of the monsoon weather phenomenon.

Relevant for farmers in the region

"The delta-18-O value tells us something about the strength of the monsoon, but not how much precipitation falls and how the rain spreads over time," explains Sebastian Breitenbach from the RUB Institute of Geology, Mineralogy and Geophysics. "But that is in fact the crucial information," adds Ola Kwiecien. "For a farmer, it makes a big difference whether precipitation falls constantly and reliably over a certain period of time, or whether surprising and extreme rainfall alternates with longer dry periods."

Geoscientists reconstruct the climate of the past by analysing dripstones
The Mawmluh Cave in north-eastern India is located in the most humid place on Earth
[Credit: Franziska Lechleitner]


In order to gather clues on the seasonal distribution of rainfall, the researchers defined additional measured values. While the delta-18-O value is a supra-regional parameter that tells them something about the distant sources of monsoon rainfall, other parameters record local phenomena, including the ratio of different elements such as strontium or magnesium to calcium or the ratio of different calcium isotopes in the dripstone. This isotope ratio, known as the delta-44-Ca value, has so far rarely been applied to cave samples.

Precipitation in the vicinity of the cave

During dry winter and longer dry periods, a phenomenon occurs in the karst rock above the cave that affects the elemental conditions in the dripstone. If rain falls over the Mawmluh Cave, it seeps through the soil, dissolves calcium from the rock and transports it into the cave. The calcium is stored in a dripstone formed by the water; the dripstone, which grows during a moist phase, thus has a high calcium content compared to other elements.

Geoscientists reconstruct the climate of the past by analysing dripstones
The composition of the dripstones in the cave reveals something about the climate of the past
Credit: Franziska Lechleitner]


However, during the dry period between November and May, some of the calcium can get lost on the way, if there are any air-filled cavities in the rock. These cause calcium to precipitate before it reaches the cave, while elements such as strontium and magnesium remain in the water, are transported to the dripstones and integrated into them. The ratio of magnesium or strontium to calcium in the dripstone thus indicates whether there was much or little rain in the immediate vicinity of the cave. The delta-44-Ca value also provides clues on the precipitation near the cave and, moreover, allows researchers to gain more information on the intensity of the dry phase.

The combination of these different parameters enabled the researchers to reconstruct changes in precipitation during the monsoon and non-monsoon periods and, consequently, to gain insight into the distribution of precipitation before, during and after the last interglacial period.

Monsoon was less reliable

"On the whole, our data show that the Indian monsoon was less reliable in the last interglacial period than it is today, which suggests that global warming today might be having the same effect," concludes Ola Kwiecien. "This tallies with the tendency for weather extremes to become more frequent." According to the researchers, human impact on the climate in the Indian summer monsoon has not yet fully manifested itself. If the assumptions underlying the current study are correct, however, this could change in the next 20 to 30 years.

Source: Ruhr-University Bochum [November 12, 2019]



* This article was originally published here

2019 November 15 M16 and the Eagle Nebula Image Credit &...



2019 November 15

M16 and the Eagle Nebula
Image Credit & Copyright: Martin Pugh

Explanation: A star cluster around 2 million years young surrounded by natal clouds of dust and glowing gas, M16 is also known as The Eagle Nebula. This beautifully detailed portrait of the region was made with groundbased narrow and broadband image data. It includes cosmic sculptures made famous in Hubble Space Telescope close-ups of the starforming complex. Described as elephant trunks or Pillars of Creation, dense, dusty columns rising near the center are light-years in length but are gravitationally contracting to form stars. Energetic radiation from the cluster stars erodes material near the tips, eventually exposing the embedded new stars. Extending from the ridge of bright emission at lower left is another dusty starforming column known as the Fairy of Eagle Nebula. M16 lies about 7,000 light-years away, an easy target for binoculars or small telescopes in a nebula rich part of the sky toward the split constellation Serpens Cauda (the tail of the snake).

∞ Source: apod.nasa.gov/apod/ap191115.html

ESA missions team up to map cosmic rays across Solar System









ESA - European Space Agency patch.

November 13, 2019

ESA spacecraft dotted across the inner Solar System carried out a census of deep space radiation during an entire 11-year solar cycle – and discovered a location where radiation levels remained mysteriously lower than elsewhere.

Cosmic rays across Solar System

The survey was based mainly on results from a shoebox-sized instrument called the Standard Radiation Environment Monitor (SREM), placed aboard several ESA spacecraft.

“The SREM has been flown on multiple ESA missions, mainly for engineering purposes,” says ESA astronomer Erik Kuulkers. “It is used to monitor the rates of highly energetic particles that can cause damage to spacecraft components – as well as living tissue.”

Standard Radiation Environment Monitor (SREM)

“Its results help us to protect spacecraft systems by alerting us to high radiation events, so we can switch operating modes accordingly,” adds ESA space environment specialist Hugh Evans. “SREM data have also served to improve the accuracy of our radiation environment models.”

“But as this study demonstrates, the instrument’s data also have wider scientific value,” explains Thomas Honig, the ESA trainee overseeing the study.

“Our focus here was on galactic cosmic rays – protons and heavy atomic nuclei, typically produced by supernovas or other violent cosmic events – to see how their incidence changed in line with the shifting nature of our own Sun as it went through its 11-year solar cycle.”

Integral gamma-ray observatory

The work was based on cross-calibrated results from the SREM units on ESA’s Rosetta comet chaser beyond Mars; the Herschel infrared and Planck microwave observatories at Lagrange point 2, 1.5 million km from Earth; the Integral gamma-ray observatory with its elongated orbit that takes it a maximum 153 000 km from Earth; and the Proba-1 Earth-observing mission in a 600-km altitude Earth orbit.

As an additional data point the team included radiation data from NASA’s Mars Odyssey spacecraft in orbit around the Red Planet. Its High-Energy Neutron Detector (HEND) detects secondary particles produced by interactions of primary galactic cosmic rays with the martian surface, so its results provided indirect cosmic ray measurements.

“We were able to observe the same radiation from different locations in the Solar System using mostly the same instrument,” says ESA planetary scientist Olivier Witasse.

 SREM mounted on Rosetta

“We found that the intensity of galactic cosmic rays within the inner Solar System are related to the Sun’s current activity, because the Sun’s magnetic field and solar wind can cause them to dissipate – in the same way that Earth’s own magnetic field keeps us safe from space radiation.”

A ‘radial gradient’ was also observed, due to the diminishing shielding provided by the solar magnetic field towards the outer solar system.

To ensure the count rates they were collating came from cosmic rays rather than other radiation sources, the team used the highest-energy channel of the SREM. They also eliminated time periods known to be associated with ‘solar proton events’ from Sun-emitted particles, using ESA’s Solar Proton Event Archive gathered from satellites in geostationary orbit. In the case of Integral, whose orbit passes through energetic particles trapped within Earth’s magnetic field, only high-altitude data was included.

Rosetta at comet

Rosetta was the most far-travelled of all the missions, venturing up to 4.5 times the distance from Earth to the Sun due to its rendezvous with target Comet 67P/Churyumov–Gerasimenko in 2014. It also diverted from the Solar System’s ‘ecliptic plane’ – the roughly flat plane within which the planets orbit around the Sun.

“Rosetta’s SREM showed a mysterious 8% reduction in cosmic ray flux compared to interplanetary space, as the spacecraft reached the comet,” explains ESA’s Rosetta project scientist Matt Taylor. “We could not account for this due to the spacecraft’s position relative to the Sun, or the comet nucleus serving as a shield, since for the majority of the time its angular size relative to Rosetta would have been insignificant.

Tracking the sun

“Similarly, there is no obvious link between the increasing level of nucleus activity as the comet got closer to the Sun, and its surrounding ‘coma’ cloud extended – but the potential shielding of the plasma environment associated with the cometary gas and dust emission cannot be ruled out.”

This most recent solar cycle minimum has been exceptionally long and quiet, notes ESA space environment specialist Petteri Nieminen.

Comparing Rosetta and Integral SREM results

“This has resulted in much higher cosmic ray incidence and related doses than our engineering models would have predicted for a ‘traditional’ solar minimum. So our findings are of interest when it comes to predicting the resilience of future missions into deep space – including human expeditions – since for these the radiation doses and effects will be dominated by cosmic rays.”

A report on the results was published in the European Geoscience Union’s Annales Geophysicae journal.

Space risks – Fighting radiation

This was a joint study between ESA’s Directorate of Science and Directorate of Technology, Engineering and Quality, collaborating with researchers from the Institute of Experimental and Applied Physics of Germany’s Kiel University, the School of Earth and Space Sciences of the University of Science and Technology of China, the Department of Physics and Astronomy of the UK’s Leicester University and Johannes Gutenberg University in Germany.

Related links:

Space Engineering & Technology: http://www.esa.int/Enabling_Support/Space_Engineering_Technology

ESA’s Rosetta: http://www.esa.int/Science_Exploration/Space_Science/Rosetta_overview

Herschel: https://www.esa.int/Science_Exploration/Space_Science/Herschel_overview

Planck: http://www.esa.int/Science_Exploration/Space_Science/Planck_overview

Integral: http://www.esa.int/Science_Exploration/Space_Science/Integral/Integral_overview

NASA’s Mars Odyssey: https://mars.nasa.gov/odyssey/

High-Energy Neutron Detector (HEND): https://mars.nasa.gov/odyssey/mission/instruments/grs/

European Geoscience Union’s Annales Geophysicae journal: https://www.ann-geophys.net/37/903/2019/

Images, Text, Credits: European Space Agency (ESA).

Greetings, Orbiter.ch

* This article was originally published here

First evidence of feathered polar dinosaurs found in Australia


A cache of 118 million-year-old fossilized dinosaur and bird feathers has been recovered from an ancient lake deposit that once lay beyond the southern polar circle.

First evidence of feathered polar dinosaurs found in Australia
Australian Feathered Polar Dinosaur
[Credit: Peter Trusler]
Feathered dinosaur fossils are famous, but known from a handful of localities worldwide. Examples from the Southern Hemisphere are especially rare, and mainly include only isolated feathers.

An international team of scientists has analyzed a collection of 10 such fossil feathers found in Australia, which reveal an unexpected diversity of tufted hair-like 'proto-feathers' from meat-eating dinosaurs, together with downy body feathers, and wing feathers from primitive birds that would have been used for flight.

Uniquely, the fossil feathers from Australia were all entombed in fine muddy sediments that accumulated at the bottom of a shallow lake close to the South Pole during the Age of Dinosaurs.


"Dinosaur skeletons and even the fragile bones of early birds have been found at ancient high-latitudes before. Yet, to date, no directly attributable integumentary remains have been discovered to show that dinosaurs used feathers to survive in extreme polar habitats", said Dr Benjamin Kear from Uppsala University in Sweden, a leading author on the study.

"These Australian fossil feathers are therefore highly significant because they came from dinosaurs and small birds that were living in a seasonally very cold environment with months of polar darkness every year".

The fossil feathers were discovered in the Koonwarra Fish Beds Geological Reserve, which is a heritage listed site 145 km southeast of Melbourne in Victoria, Australia.

First evidence of feathered polar dinosaurs found in Australia
Carnivourous Dinosaur Protofeather from Koonwarra
[Credit: Melbourne Museum]
"Fossil feathers have been known from Koonwarra since the early 1960s, and were recognized as evidence of ancient birds, but have otherwise received very little scientific attention. Our study is thus the first to comprehensively document these remains, which include new specimens that were examined using cutting-edge technologies", said Dr Thomas Rich of the Melbourne Museum in Australia, who has led numerous expeditions to the Koonwarra locality.

A suite of advanced microscopic and spectroscopic techniques was employed to determine the anatomy and preservation of the Koonwarra fossil dinosaur and bird feathers.

"The Koonwarra feathers are preserved in incredible detail", said fossil bird expert Professor Patricia Vickers-Rich of Monash University and the Swinburne University of Technology in Melbourne.


"There are even tiny filament-like structures that would have 'zipped' the feather vanes together, just as in the flight feathers of modern birds".

However, unlike the structurally complex feathers of birds today, which are characterized by interlocking branches called barbs and barbules, different kinds of small dinosaurs had coverings that comprised much more simpler hair-like 'proto-feathers'.

"Dinosaur 'proto-feathers' would have been used for insulation", said Dr Martin Kundrat, of Pavol Jozef Safarik University in Slovakia, a leading author on the study.

First evidence of feathered polar dinosaurs found in Australia
Early Bird Feather with Colour Patterning from Koonwarra
[Credit: Melbourne Museum]
"The discovery of 'proto-feathers' at Koonwarra therefore suggests that fluffy feather coats might have helped small dinosaurs keep warm in ancient polar habitats".

Microscopic remains of possible melanosomes - cellular structures that contain colour pigments - were also detected on several of the fossil feathers found at Koonwarra.

These traces occurred across the uniformly dark feather surfaces, as well as in distinct bands that might represent original patterning from the polar dinosaurs and birds.

Melanic residues have been reported on fossil feathers from elsewhere around the world, and are widely acknowledged as indicators of dinosaur colouration.


The densely packed fossil melanosomes occurring on the Koonwarra feathers could suggest dark colours that perhaps assisted in camouflage, visual communication, and/or heat absorbance in cold polar climates.

Possible preservation of biomolecules was also assessed, but proved to be too degraded, and were apparently lost during weathering of the rock.

The Koonwarra fossil feathers provide the first record of dinosaur integument from the ancient polar regions, and hint what was once a global distribution of feathered dinosaurs and early birds.

Some of the fossil feathers found at Koonwarra are on display in the '600 Million Years' exhibition at the Melbourne Museum in Australia.

The discovery is published in Gondwana Research.

Source: Uppsala University [November 12, 2019]



* This article was originally published here

50 Years Ago: Return to the Moon













NASA - Apollo 12 Mission patch.

Nov. 14, 2019

The United States was ready to send its second team of astronauts, Commander Charles “Pete” Conrad, Command Module Pilot (CMP) Richard F. Gordon, and Lunar Module Pilot (LMP) Alan L. Bean, on a Moon landing mission. The months of training since they were assigned as the Apollo 12 crew in April 1969 were behind them, and now launch day had arrived. The goal of the first mission was to prove that a human landing on the Moon could be accomplished. Apollo 12 was more ambitious, aiming for a pinpoint landing in the Ocean of Storms and completing two Extravehicular Activities (EVAs) or spacewalks on the lunar surface during a longer stay of 31.5 hours. An added bonus of the pinpoint landing involved a visit to Surveyor 3, a robotic spacecraft that had been on the Moon since April 1967. Scientists and engineers eagerly awaited the astronauts returning pieces of the spacecraft to better understand the effects of the extended stay under lunar conditions.

Left: Apollo 12 crew of (left to right) Conrad, Gordon, and Bean. Right: The Apollo 12 crew patch.

The countdown for the second Moon landing mission continued smoothly until technicians began loading liquid hydrogen into the Apollo spacecraft’s Service Module (SM) fuel cell reactant tank. The tank’s insulation was damaged and wouldn’t hold the required supercold temperatures. Managers decided to hold the countdown while the tank was replaced with the one from the Apollo 13 SM. The repair completed, the countdown continued without further issues. Both President Richard M. Nixon, accompanied by First Lady Pat Nixon, NASA Administrator Thomas O. Paine, and astronaut Frank Borman, as well as Vice President Spiro T. Agnew, accompanied by Apollo 8 astronauts James A. Lovell and William A. Anders (since August 1969, the Executive Secretary of the National Space Council chaired by Agnew), attended the Apollo 12 launch – Nixon’s presence marking the first time a sitting President attended a human spaceflight launch.

Left: President Nixon (left of center), with the First Lady and NASA Administrator Paine (holding umbrella) watch the Apollo 12 launch. Right: Vice President Agnew (center) watches the launch from Firing Room 2, accompanied by astronauts Lovell (left) and Anders.

The astronauts’ day began with a 6 AM wake-up call from Chief of the Astronaut Office Thomas P. Stafford. They enjoyed the traditional prelaunch breakfast with Stafford, Apollo Spacecraft Program Manager James A. McDivitt, backup LMP James B. Irwin, and Charles J. “Chuck” Tringali, the leader of the crew support team, as well as an unofficial crew mascot named “Irving,” a stuffed gorilla dressed in a smock and hard hat. After donning their spacesuits, the crewmembers rode the Astrovan to Launch Pad 39A. Workers in the White Room assisted them into their seats in the Command Module (CM) Yankee Clipper, Conrad into the left hand couch, Bean into the right, and finally Gordon into the middle. After the pad workers closed the hatch to the capsule, the astronauts settled in for the final two trouble-free hours of the countdown.

Left: Prelaunch breakfast in crew quarters (left to right, facing the camera) Stafford, Conrad, Gordon, and Tringali; (left to right, backs to the camera) McDivitt, Bean, and Weitz; Irwin is out of the picture to the right; behind Conrad is “Irving,” the crew mascot. Right: Apollo 12 astronauts (front to back) Conrad, Gordon, and Bean leaving crew quarters to board the Astrovan for the ride to Launch Pad 39A.
 
Left: Engineers in KSC’s Firing Room 2 during the final phases of the Apollo 12 countdown. Right: Flight Director Griffin (seated) with Director of Flight Operations Christopher C. Kraft in MCC during the Apollo 12 launch.

Lift off came precisely at 11:22 AM EST on Nov. 14, 1969, with the Saturn V launching Apollo 12 into the dark and rainy morning sky. Engineers in KSC’s Firing Room 2 who had managed the countdown handed over control of the flight to the Mission Control Center (MCC) at the Manned Spacecraft Center (MSC), now the Johnson Space Center in Houston, as soon as the rocket cleared the launch tower. In MCC, the Gold Team led by Flight Director Gerald D. “Gerry” Griffin took over control of the mission. The Capcom, or capsule communicator, the astronaut in MCC who spoke directly with the crew, during launch was Gerald P. “Jerry” Carr. Apollo 11 astronauts Neil A. Armstrong and Edwin E. “Buzz” Aldrin watched the launch from the MCC Visitors Gallery. The flight proceeded normally for the first 36 seconds, with Conrad even commenting that, “It’s a lovely liftoff. It’s not bad at all,” when everything went haywire. With Apollo 12 at about 6,600 feet altitude and flying through clouds, observers on the ground noted lightning striking the launch pad. Onboard the spacecraft, Conrad saw a bright flash, followed by many of the spacecraft’s electronics going offline, causing the three power-generating fuel cells to go offline. Fortunately, the Saturn V rocket that was guiding the launch was unaffected and continued to operate normally. In Mission Control, data on controllers’ displays turned to gibberish.

Liftoff of Apollo 12 as seen from the Launch Umbilical Tower. Note the raindrops on the camera lens.

A second event 52 seconds into the flight caused the spacecraft guidance navigation system to go offline. Flight Director Griffin turned to the Electrical, Environmental, and Communications (EECOM) console, staffed by a young engineer named John W. Aaron, for answers and solutions. Aaron monitored the spacecraft’s systems through the two incidents, especially when his data display went from normal to garbled, and remembering a test a year earlier during which he saw similar signals, he correctly deduced that the spacecraft’s Signal Conditioning Equipment (SCE) must have suffered some unknown upset and went offline. The simple solution to restoring it to normal function involved moving a seldom-used switch from its Normal to its Auxiliary position. He informed Griffin, who instructed Carr to make the call up to the crew. Bean recalled that the switch was located on his panel and carried out the requested action. Several seconds later, Aaron reported seeing good data on his screen. His quick action saved the launch from the results of what turned out to be lightning striking the rocket twice. Once Conrad understood the cause of the excitement, he radioed to Houston, “I think we need to do a little more all-weather testing.” Relive the excitement of the launch and the lightning strikes here: https://www.youtube.com/watch?v=31qt9jgtMMI

Left: Last vestiges of the Saturn V’s exhaust plume on Launch Pad 39A. Right: Lightning striking Launch Pad 39A shortly after the launch of Apollo 12.

The rest of the ascent continued without incident and 11 and a half minutes after liftoff, Apollo 12 was in a near-circular 118-by-115-mile orbit around the Earth. For the next two and a half hours, as the Apollo spacecraft still attached to its S-IVB third stage orbited the Earth, the astronauts and MCC verified that all systems were functioning properly following the lightning strikes. Carr then called up to the crew, “The good word is you’re Go for TLI,” the Trans Lunar Injection, the second burn of the third stage engine to send them on their way to the Moon. In his characteristic fashion, Conrad replied, “Hoop-ee-doo!  We’re ready! We didn’t expect anything else!” The S-IVB’s single J-2 engine fired for 5 minutes and 44 seconds, increasing Apollo 12 speed to 24,145 miles per hour, fast enough to escape Earth’s gravity.

Left: One of the Spacecraft LM Adapter panels silhouetted against the Earth – Central America and the western Pacific Ocean are visible. Right: LM Intrepid still attached to the S-IVB.

The next major event, the separation of the Command and Service Module (CSM) Yankee Clipper from the S-IVB stage, took place about 25 minutes later, by which point Apollo 12 had reached an altitude of 4,300 miles. Gordon turned Yankee Clipper around and slowly guided it to a docking with the LM Intrepid still attached to the top of the S-IVB. Conrad commented during the maneuver, “I got an awful pretty looking Intrepid sitting out the window here, gang. We'll go get her.” The astronauts turned on the color TV camera, providing a detailed view as they approached Intrepid. After the docking, the crew pressurized the LM before Gordon backed away from the third stage, extracting the LM in the process, and completing the Transposition and Docking maneuver. Apollo 12 had now reached an altitude of about 13,000 miles, and the crew described the apparent size of the Earth as that of a basketball. The S-IVB performed an evasive maneuver to ensure it wouldn’t interfere with Apollo 12 as it made its way to the Moon. A second maneuver about 20 minutes later sent the S-IVB toward the trailing edge of the Moon and into solar orbit.

Left: View of the receding Earth shortly after the Transposition and Docking maneuver.
Right: View of MCC during one of the TV broadcasts of the translunar coast.

The astronauts settled down for their first meal since launch, ham sandwiches, and finally removed their suits while in Mission Control Flight Director M.P. “Pete” Frank’s Orange Team took over the consoles, with astronaut Edward G. Gibson the new Capcom. Because of the accuracy of the S-IVB’s TLI burn, controllers decided to cancel the first mid-course correction (MCC-1) maneuver. Conrad and Bean opened the hatches to the LM to conduct their first inspection and found Intrepid to be very tidy. By the time they finished the LM inspection, they described the Earth as the size of a volleyball. Gordon put the stack in PTC mode. Before turning in for their first night’s sleep in space, Conrad requested that the ground play back for them the tape of their conversations during the launch. Flight Director Clifford E. “Cliff” Charlesworth and his Green Team of controllers took over, with Don Lind as the new Capcom. By the time they went to sleep, they had traveled out to more than 90,000 miles.

Left: Capcom Weitz (left) with Apollo 13 astronaut Thomas K. Mattingly and Capcom Carr in MCC. Right: Flight Directors Griffin (left) with Apollo 12 backup Commander David R. Scott and Capcom Gibson in MCC.

While the crew slept another shift change in Mission Control brought Flight Director Griffin back to his console, this time joined by Paul J. Weitz as the new Capcom. By the time the astronauts awoke to start their first full day in space, their distance from Earth had increased to about 125,000 miles. After they finished breakfast, they passed the halfway point on their journey to the Moon, an equidistant 129,947 miles from both the Earth and the Moon. They turned on the color TV to show viewers a midcourse correction maneuver (MCC-2), an 8.8-second firing of the SM’s Service Propulsion System (SPS) engine, to reduce the low point of their approach to the Moon from 822 miles to 69 miles, the correct altitude for the Lunar Orbit Insertion (LOI) burn. The rest of the day was quiet, with the crew monitoring spacecraft systems. Conrad radioed down that the Earth now appeared about the size of a golf ball held at arm’s length. By the time they settled down for their second sleep period of the mission, they had reached a distance of more than 165,000 miles from Earth.

Left: The Earth continuing to shrink in apparent size during the translunar coast. Right: Flight Directors (left to right) Charlesworth (in dark jacket), Lunney, and Griffin discuss the flight’s progress with Scott.

At crew wake up for flight day 3, Apollo 12 had reached a distance of 185,000 miles from Earth and continued slowing as Earth’s gravity maintained its pull on them. The astronauts spent the morning with Capcom Weitz calling up some news and sports scores while they ate breakfast, followed by an exchange over whether a day-old can of tuna spread was still good to eat (the consensus was not). Weitz also informed the crew that since their trajectory was still so precise, Mission Control decided to cancel the third MCC maneuver. As Apollo 12 approached the Moon, the astronauts reported that as they flew out in front of it, they could see less and less of it as a greater portion of the Moon entered into darkness. The astronauts provided a live TV broadcast showing them opening the hatches to the LM Intrepid to begin a more thorough checkout of that vehicle. In the attitude that provided optimal lighting for the TV broadcast, the crew could see the Earth out the left hand window of the CM, the Sun shining through the center window, and the Moon out the right hand window. During the telecast, they provided viewers with excellent shots of the crescent Earth and Moon, now appearing about the same size.  After they settled in for the night, Apollo 12 crossed into the Moon’s gravitational sphere of influence and began to accelerate toward its destination.

Left: The Earth continues to grow smaller. Right: The crescent Moon as it appeared to the Apollo 12 crew shortly before entering orbit.

The Apollo 12 astronauts awoke for their fourth mission day to find themselves a mere 15,671 miles from the Moon and still accelerating. They provided ever increasingly detailed descriptions of the Moon as its apparent size grew larger and larger. Flight Director Glynn S. Lunney decided that the velocity change that would have been accomplished by MCC-4 was so minor that it would be incorporated into the LOI burn. As they slipped into the Moon’s shadow, they were able to observe the solar corona. As they continued to accelerate toward the Moon, they oriented their spacecraft into the correct attitude for the LOI maneuver. Shortly after, as previous missions had done before them, Apollo 12 sailed behind the Moon and all contact with Earth was cut off. Thirteen minutes later, they fired the SPS engine for the six-minute Lunar Orbit Insertion-1 (LOI-1) burn, reducing Apollo 12’s velocity to allow it to enter into an elliptical 194-by-72-mile orbit around the Moon. Back in Houston, mission controllers and managers anxiously awaited the reacquisition of signal with Apollo 12 – if the engine fired successfully, they would receive the signal after 32 minutes; if it didn’t fire, that signal would arrive 7 minutes earlier.

To be continued….

Related links:

Apollo: https://www.nasa.gov/mission_pages/apollo/index.html

Apollo 12: https://www.nasa.gov/mission_pages/apollo/apollo-12

NASA History: https://www.nasa.gov/topics/history/index.html

Images, Text, Credits: NASA/Kelli Mars/JSC/John Uri.

Greetings, Orbiter.ch

* This article was originally published here

Why words make language


From hieroglyphics to emojis, and grunts to gestures, humans have always used multiple modes to communicate, including language.

Why words make language
Modes of communication [Credit: Wits University]
If you've ever sent a text using emojis, which the recipient received and understood, then you've communicated in a new language code. Communication codes have been with us since the grunts of our ancestors developed in to the first languages—Aramaic, Sanskrit, Tamil—the latter having made an appearance in 300 BC and considered the world's oldest language.

Dr. Gilles Baro, a sociolinguist at Wits, says that what we consider languages today are "organised, systematised guides to communication". "People have always communicated using multiple modes, such as gestures, sounds, words, scripts and images. Languages are one of those modes and they are not 'invented'. Rather, people—usually the elite—decide on a norm for communication, and that is what we consider 'language' today."

Linguistic migration

Over time, this code evolves, says Maxwell Kadenge, Associate Professor and Head of the Department of Linguistics in the School of Literature, Language and Media at Wits. And where this code will be in future is anyone's guess.


"Languages evolve naturally as a result of the migration of people, which in turn results in languages getting into contact with each other. Think of Afrikaans, which was originally spoken by the Dutch, but began to develop distinct characteristics as a result of its contact and borrowing from South African languages, especially Khoe and San languages."

Similarly, says Kadenge, South African spoken languages that evolved because of contact between existing languages include Fanagalo and Tsotsitaal. "Both of them have borrowings from Bantu languages like Zulu, Xhosa, English and Afrikaans. Chilapalapa developed in Zimbabwe [then Rhodesia] from the contact between English, Shona varieties and Zambia languages," he says.

Brave new word

Baro says that along with migration, new environments and technology also influence how language evolves. Emojis and text language are an example of how spoken language has merged with digital communication.

"Today, considering the internet, language is more open and in a way more vulnerable to be changed or influenced. We are exposed to a lot more variations than in the past. For example, a study done at the University of Cape Town showed the increasing use of the word 'like' as a quotative, hedge, or discourse particle by young South Africans was influenced by their exposure to North American popular culture, via movies and songs. Often the accent and vocabulary of a nearby community will influence a language too, through the borrowing of words."

A quotative is a grammatical device to mark quoted speech—essentially "spoken quotation marks"—while hedge and discourse particles make speech less direct and manage the flow of dialogue.

Degrees of understanding

"The word 'language' is broad and fluid, as it has both linguistic and political connotations. In simple terms, a language is a communally owned means of communication, which is passed on from one generation to the other through the process of socialisation," says Kadenge.


The reason we have differences in languages and dialects is essentially to understand each other in a particular space and time. "One of the criterion that are used to consider varieties such as dialects of the same language, or as distinct languages, is mutual intelligibility. This simply refers to the degree to which speakers of different languages understand each other in the same conversation," he says.

Kadenge explains: "Normally, varieties that are mutually intelligible are considered dialects of the same language. For example, the Zimbabwean language—Shona—is made up of four main dialects, namely Karanga, Zezuru, Korekore and Manyika, whose degree of mutual intelligibility varies. These varieties are considered dialects of the Shona language. However, Scandinavian languages—Danish, Norwegian and Swedish—are mutually intelligible, just like the Shona dialects, but are considered different languages, probably because they are spoken in different countries. Against this background, the question on what makes a language a language is not easy to define."

EmpoWORDment

Some would argue that language is steeped in our identity, and can separate communities. Baro says variations in language are also clues to particular traits of identity. "So when hearing someone use language, we can guess their gender or sex, race, class, etc."

Language, being a social aspect of life, has the power to divide as much as it brings people together. In South Africa particularly, it is contentious when public discussions are held in a language that only some can understand. People who cannot speak the language would undoubtedly feel excluded from the group.

"Languages signify identity and belonging. This is primarily because people who speak the same language understand each other, the languages contain words that all the members of a community understand," Kadenge says.

"In South Africa, due to internal colonialism, some big and politically powerful groups tend to suppress smaller groups. This is evident in language policies and practices. Why is it that the national anthem has English, Afrikaans, Nguni and Sotho languages but does not include Venda and Tsonga languages? The national anthem is one of the main national symbols; sacrosanct heritage and rallying point of the country. This tells you who is in power and who is not. Language symbolises power, and when you exclude some languages in the linguistic landscape, such as a national anthem, you are disempowering the speakers."

Culture carrier

But language also allows us to pass our cultural values and sensibilities from one generation to another, says Kadenge. "Hence, we usually say language is a carrier of culture. It is the means through which we share our values and socialise our children."


Simultaneously, language also allows us access into other cultures. "Many people around the world now have access to the Chinese culture because the Chinese language is spreading around the world through the establishment of Confucius Institutes and the teaching of the language all over the world. This is how English culture has spread around the world. English is now considered a global language. Right now, South Africa is strengthening its links with East Africa by introducing the teaching of Swahili in its education system. It is why Swahili has been taught at the University of Zimbabwe for a while."

Thinking aloud

While the number of spoken languages is said to be reducing globally, language code is developing in other ways. English is being manipulated, moulded and restructured using psycholinguistics, or psychology of language, which considers the way that it is shared and understood.

Baro adds, "Agency is important, meaning that people purposefully make use of different variations of language in order to perform aspects of identity. Formality versus informality, humour, or wanting to sound serious, for example."

"Because of our agency to use language as one form of communication, we get to express ourselves using language based on how the language and its different forms or variations are perceived in society. One will use different forms of language if they want to appear friendly or unfriendly, for example. This is why language is considered a system, because each word, sound, accent, variant, indexes a particular meaning," says Baro.

Author: Shanthini Naidoo | Source: Wits University [November 12, 2019]



* This article was originally published here

Final Spacewalk Preps During Biology, Physics Studies













ISS - Expedition 61 Mission patch.

November 14, 2019

The Expedition 61 crew is about to kick off a series of complex spacewalks on Friday to repair the International Space Station’s cosmic particle detector. They will have one more spacewalk review today while continuing advanced biology research.

Spacewalkers Luca Parmitano and Andrew Morgan readied the Quest airlock, their U.S. spacesuits and tools for Friday’s excursion set to begin at 7:05 a.m. EST. The duo then joined Flight Engineers Jessica Meir and Christina Koch for a final procedures review. All four astronauts called down to Mission Control to discuss their readiness with spacewalk experts on the ground. Live NASA TV coverage begins at 5:30 a.m.


Image above: The six-member Expedition 61 crew, wearing t-shirts printed with their crew insignia, gathers for a playful portrait inside the International Space Station’s Zvezda service module. From left are, Flight Engineers Andrew Morgan, Oleg Skripochka, Jessica Meir, Christina Koch and Alexander Skvortsov and Commander Luca Parmitano. Image Credit: NASA.

Meir and Koch spent the rest of Thursday on space research and lab upkeep. Meir conducted a test run of a 3-D bioprinter before the device will manufacture complex human organ tissue shapes. Koch measured airflow in the station then serviced microbe samples to extract and sequence their DNA.

Cosmonauts Alexander Skvortsov and Oleg Skripochka focused on their complement of science and maintenance in the station’s Russian segment. Skvortsov updated cargo inventory and explored plasma physics for insights into advanced spacecraft designs. Skripochka collected radiation readings and studied how a crew adapts to piloting in space.

Related links:

Expedition 61: https://www.nasa.gov/mission_pages/station/expeditions/expedition61/index.html

NASA TV: https://www.nasa.gov/multimedia/nasatv/index.html

3-D bioprinter: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=7599

Sequence astronaut DNA: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7687

Plasma physics: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1192

Piloting in space: https://www.energia.ru/en/iss/researches/human/24.html

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

Image (mentioned), Text, Credits: NASA/Mark Garcia.

Best regards, Orbiter.ch

* This article was originally published here

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