пятница, 24 августа 2018 г.

Global25 workshop 3: genes vs geography in Northern Europe

To produce the intra-North European Principal Components Analysis (PCA) plot below, download this datasheet, plug it into the PAST program, which is freely available here, then select all of the columns by clicking on the empty tab above the labels, and choose Multivariate > Ordination > Principal Components.



Of course, if you’re in the possession of your own personal Global25 coordinates, you can add yourself to this plot. Please keep in mind, however, that the vast majority (>90%) of your ancestry must be from north of the Alps, Balkans and Pyrenees to receive a sensible outcome. Also please ensure that all of the columns in the datasheet are filled out correctly, including the group column, otherwise your position on the plot will be skewed.
See also…
Global25 workshop 1: that classic West Eurasian plot
Global25 workshop 2: intra-European variation
Global25 PAST-compatible datasheets
Modeling genetic ancestry with Davidski: step by step

Source


Clay pot with hundreds of silver and gold coins found at Bulgaria’s Kaliakra Fortress

An archaeological team working at the site of the Kaliakra Fortress on Bulgaria’s northern Black Sea coast have found a small clay pot containing close to 1000 objects, including silver and gold coins and jewellery, the National History Museum announced.











Clay pot with hundreds of silver and gold coins found at Bulgaria’s Kaliakra Fortress
Credit: National History Museum

The find was made on August 17 2018. The items in the clay pot included 873 silver and 28 gold coins, 11 appliqués and buckles, 28 silver and bronze buttons, 11 gold earrings, two rings, one of them gold, and four beads made of precious stones and gold.
The discovery, beneath the floor of a room that was burnt in the 14th century, happened during the 15th year of excavations at the fortress. The archaeological investigations are funded by the Ministry of Culture, Kavarna municipality and the National History Museum. The team is headed by the director of the National History Museum, Associate Professor Bonnie Petrunova.











Clay pot with hundreds of silver and gold coins found at Bulgaria’s Kaliakra Fortress
Credit: National History Museum

An initial examination of a small part of the coins established that not only are there silver Ottoman coins, but also many Bulgarian ones. The Ottoman coins make up about 60 per cent. Basically, they are from the time of Sultan Bayazid Yildirum (1389-1402), and a small part from that of his predecessor, Murad I (1362-1389).
All the jewels were concealed at the end of the 14th century during one of the dramatic attacks on the capital of the Despotate of Dobruja, the National History Museum’s statement said .











Clay pot with hundreds of silver and gold coins found at Bulgaria’s Kaliakra Fortress
Credit: National History Museum

One of these events is described in one of the chronicles of this time, which notes that in 1399 the Tatars of the Aktav horde invaded Varna and other towns along the Northern Black Sea coast. In 1401, the Tatars of Aktav, who was known as the Dobrudzha Tatar, were defeated and displaced in various villages such as Provadia, Rusokastro and others. It is possible that one of their commanders has gathered the treasure discovered at Kaliakra. It appears that he had seized them from different people and places and hid them under the floor of his house shortly before it was burnt.
In the same building, during the 2014-2017 surveys, part of a silver church bookcase, a white jade belt buckle, and 26 small copper coins from the time Bayezid I Yilderham (1389-1402) ), were found.











Clay pot with hundreds of silver and gold coins found at Bulgaria’s Kaliakra Fortress
Credit: National History Museum

The building itself was built directly on the ruins of ancient buildings. Burial sites were found nearby. In one of the graves, in 2014, three gold coins, dating from the Nicene dynasty in the 13th century were found.


This is the third treasure to be found at the site, following two finds in earlier years, one of 60 coins, and another of 80 coins, gold earrings and small ornaments.


Source: The Sofia Globe [August 22, 2018]



TANN



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Napoleon’s defeat at Waterloo caused in part by Indonesian volcanic eruption?

Electrically charged volcanic ash short-circuited Earth’s atmosphere in 1815, causing global poor weather and Napoleon’s defeat, says new research.











Napoleon's defeat at Waterloo caused in part by Indonesian volcanic eruption?
Napoleon’s retreat from the Battle of Waterloo. Image: After a painting by Steuben
[Credit: Hulton Archive/Getty Images]

Historians know that rainy and muddy conditions helped the Allied army defeat the French Emperor Napoleon Bonaparte at the Battle of Waterloo. The June 1815 event changed the course of European history.


Two months prior, a volcano named Mount Tambora erupted on the Indonesian island of Sumbawa, killing 100,000 people and plunging the Earth into a ‘year without a summer’ in 1816.


Now, Dr Matthew Genge from Imperial College London has discovered that electrified volcanic ash from eruptions can ‘short-circuit’ the electrical current of the ionosphere — the upper level of the atmosphere that is responsible for cloud formation.


The findings, published in Geology, could confirm the suggested link between the eruption and Napoleon’s defeat.


Dr Genge, from Imperial’s Department of Earth Science and Engineering, suggests that the Tambora eruption short-circuited the ionosphere, ultimately leading to a pulse of cloud formation. This brought heavy rain across Europe that contributed to Napoleon Bonaparte’s defeat.


The paper shows that eruptions can hurl ash much higher than previously thought into the atmosphere — up to 100 kilometres above ground.


Dr Genge said: “Previously, geologists thought that volcanic ash gets trapped in the lower atmosphere, because volcanic plumes rise buoyantly. My research, however, shows that ash can be shot into the upper atmosphere by electrical forces.”



A series of experiments showed that that electrostatic forces could lift ash far higher than by buoyancy alone. Dr Genge created a model to calculate how far charged volcanic ash could levitate, and found that particles smaller than 0.2 millionths of a metre in diameter could reach the ionosphere during large eruptions.


He said: “Volcanic plumes and ash both can have negative electrical charges and thus the plume repels the ash, propelling it high in the atmosphere. The effect works very much like the way two magnets are pushed away from each other if their poles match.”


The experimental results are consistent with historical records from other eruptions.


Weather records are sparse for 1815, so to test his theory, Dr Genge examined weather records following the 1883 eruption of another Indonesian volcano, Krakatau.


The data showed lower average temperatures and reduced rainfall almost immediately after the eruption began, and global rainfall was lower during the eruption than either period before or after.


He also found reports of ionosphere disturbance after the 1991 eruption of Mount Pinatubo, Philippines, which could have been caused by charged ash in the ionosphere from the volcano plume.


In addition, a special cloud type appeared more frequently than usual following the Krakatau eruption. Noctilucent clouds are rare and luminous, and form in the ionosphere. Dr Genge suggests these clouds therefore provide evidence for the electrostatic levitation of ash from large volcanic eruptions.


Dr Genge said: “Vigo Hugo in the novel Les Miserables said of the Battle of Waterloo: ‘an unseasonably clouded sky sufficed to bring about the collapse of a World.’ Now we are a step closer to understanding Tambora’s part in the Battle from half a world away.”


Author: Caroline Brogan | Source: Imperial College London [August 22, 2018]



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Evidence of glass industry in ninth-century city of Samarra in Iraq

The palace-city of Samarra, capital of the former Abbasid Caliphate, was home to an advanced industry of glass production and trade, according to a study published in the open-access journal PLOS ONE by Nadine Schibille of the CNRS, France and colleagues.











Evidence of glass industry in ninth-century city of Samarra in Iraq
Glass artefacts from Samarra, including a range of vessel types, optical properties, and decorative techniques
[Credit: Images A, C and D from the Victoria and Albert Museum, London; images B and E
from the Museum für islamische Kunst/Staatliche Museen zu Berlin]

Located in Iraq about 125km north of Baghdad, Samarra was the Abbasid capital from 836-892CE. Noted for its abundance of decorative architectural glass, the city represents an important source of archaeological information on early Islamic art and architecture. However, details of the production of Samarra’s glass artefacts, as well as their role in the city’s economy, have been elusive.


In this study, the authors examined 265 Samarra glass artefacts housed in museum collections in Germany and England, including bowls, lamps, bottles, decorative and architectural glasses, and more. Trace elements in the glass, identified using mass-spectrometric analysis, offered clues to the geographic origin of the raw materials used in the making of the different types of glass artefacts.


The results suggest that a portion of Samarra’s glass was imported from other regions, such as the Levant and Egypt. But the majority of the glass artefacts were so similar in composition that the authors strongly suspect much of the glass was being produced locally. This paints a picture of a city with an important industry of glass production and trade, confirming earlier hypotheses based on writings from this time period. The fact that the highest-quality glass was used to decorate the city’s main caliphal palace suggests that glass was of great cultural and economic value at this time.


Schibille notes: “High-resolution chemical analysis of ninth-century glasses from Samarra reveals a sophisticated Abbasid glass industry as well as selective imports of specific glass objects. Our analytical data thus confirm written sources about the production of glass in the vicinity of the new capital city.”


Source: PLOS [August 22, 2018]



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Intact late Minoan tomb found in Crete

An unlooted chamber tomb containing, among others, a larnax coffin with a well-preserved skeleton of an adult in a contracted position, as well as vases in an excellent state of preservation, were excavated in the area of Ierapetra, eastern Crete, by the Lassithi Ephorate of Antiquities.











Intact late Minoan tomb found in Crete
Credit: Lassithi Ephorate of Antiquities

According to a statement from the Culture Ministry, the tomb was found during a salvage excavation conducted in an olive grove located at Rousses, about 800 metres northeast of the village of Kentri, Ierapetra.
A pit with a diametre of 1.20m and a depth of more than 2.5m was excavated in the grove after which “a chamber tomb was discovered, dug into the soft limestone of the area. The access to the tomb was made by a vertical shaft, while the entrance was sealed by stone masonry.”











Intact late Minoan tomb found in Crete
Credit: Lassithi Ephorate of Antiquities

The interior of the tomb was divided into three carved chambers, said the statement. An intact larnax coffin with the cover in place was found in the most southern one. The well-preserved skeleton was found inside. Fourteen ritual amphorae, an amphorae krater with an extended base and a drinking cup were found in front of the coffin.
In the northern chamber was found another larnax with another adult skeleton and additional vases near it. All vases are intact, of good craftsmanship and in an excellent state of preservation.











Intact late Minoan tomb found in Crete
Credit: Lassithi Ephorate of Antiquities

The announcement said that “according to the ceramic typology, and according to the first estimates, the tomb can be dated to the Late Minoan IIIA-B period, approximately from 1400 to 1200 BC.”


Source: Greek Ministry of Culture [August 23, 2018]



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Pictish symbol stone found in Scottish river

A carved Pictish symbol stone has been discovered on the banks of the River Don in Aberdeen. The find was made by fishermen in Dyce when low water levels – after the recent warm and dry weather – partially exposed the stone on the river bank.











Pictish symbol stone found in Scottish river
Credit: HES

Historic Environment Scotland (HES) said analysis confirmed it was a Pictish symbol stone. It has been removed, and will be permanently housed at a yet to be decided venue.
Kirsty Owen, deputy head of archaeology at HES, said: “We’re very excited by this find, made all the more remarkable by the brief window of opportunity we had to recover the stone before the water levels rose again.”











Pictish symbol stone found in Scottish river
Credit: HES

Bruce Mann, the local authority archaeologist for Aberdeen and Aberdeenshire, said: “The exceptional summer has led to river levels being at their lowest for decades, so there was always a chance that something new would be found. However, I certainly didn’t expect a find as stunning as this. Pictish symbol-stones are incredibly rare, and this one, with its apparent connection to the river, adds further to the discussions around their meaning and what they were used for.”


Source: BBC News Website [August 23, 2018]



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Third Venus discovered at Granada’s Roman Villa of Salar

The Roman Villa of Salar had an exceptional moment with the discovery of a third Venus. The recent discovery, during the archaeological campaign being undertaken in the area, represents a turning point for this site which, since its discovery in 2004, has become one of the reference points for archaeology in the Spanish province of Granada.











Third Venus discovered at Granada's Roman Villa of Salar
Credit: Villa Romana De Salar

In fact, the third Venus – which is in a perfect state of preservation – complements the other two similar pieces found in 2012 and 2013. However, this sculpture is larger than those previously found in the villa, which houses Roman remains dating between the first and fifth centuries AD.


Third Venus discovered at Granada's Roman Villa of Salar

Third Venus discovered at Granada's Roman Villa of Salar


Third Venus discovered at Granada's Roman Villa of Salar










Third Venus discovered at Granada's Roman Villa of Salar
Credit: Villa Romana De Salar

The ‘Capitoline Venus’ measures around 60 centimetres in its full size and reaffirms the historical importance of the Roman remains of Salar.



The discovery of the Roman villa in this western municipality came about as a result of the work begun by the Granada Provincial Council to build a wastewater treatment plant.


Source: Granada Hoy [August 24, 2018]



TANN



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OMG! Ice is Melting from Below

image

Oceans

Melting Greenland
(OMG) scientists are heading into the field this

week to better understand how seawater is melting Greenland’s ice from below. (Yes,

those black specks are people next to an iceberg.) While NASA is studying ocean

properties (things like temperature, salinity and currents), other researchers

are eager to incorporate our data into their work. In fact, University of

Washington scientists are using OMG data to study narwhals – smallish whales

with long tusks – otherwise known as the “unicorns of the sea.”


 Our researchers are also in the field right now studying how

Alaska’s ice is changing. Operation

IceBridge
, our longest airborne campaign, is using science

instruments on airplanes to study and measure the ice below.


What happens in the Arctic doesn’t stay in the Arctic (or

the Antarctic, really). In a warming world, the greatest changes are seen in

the coldest places. Earth’s cryosphere – its ice sheets, sea ice, glaciers,

permafrost and snow cover – acts as our planet’s thermostat and deep freeze,

regulating temperatures and storing most of our freshwater. Next month, we’re

launching ICESat-2, our

latest satellite to study Earth’s ice!



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


‘Tunguska’ Size Asteroid Buzzes Earth

An asteroid comparable to the to the asteroid that exploded in the Tunguska region of Siberia in 1908 buzzed past the Earth on Sunday 15, April just one day after its discovery by astronomers at the Catalina Sky Survey. The asteroid designated 2018 GE3 reached closest approach to the Earth at 06:41 UT/GMT at a distance of just 119,400 miles or around the halfway point between the Earth and Moon.


NASA estimate the asteroid to be between 48 to 110 meters in diameter which makes it even larger than the object that exploded over Siberia 100 years ago flattening 2000 square kilometers of forest (thought to be around 60m in diameter). 2018 GE3 is also up to  six times larger than the more recent 20km meteor that exploded in the sky over Chelyabinsk, Russia in February 2013 causing  damage to around 7200 buildings and injuring almost 1200 people.


Michael Jäger, Austria took this video of the 13th magnitude space rock passing through the constellation of Serpans.


Asteroid 2018 GE3 - Michael Jäger
Asteroid 2018 GE3 – Michael Jäger

spaceweather.com wrote:



“If 2018 GE3 had hit Earth, it would have caused regional, not global, damage, and might have disintegrated in the atmosphere before reaching the ground.”



What are the risks of future impacts?


This object was discovered a mere 21 hours before closest approach and goes to show that there are still medium-sized asteroids with orbits within close vicinity of the Earth that are yet to be discovered.


As a somewhat more reassuring fact, NASA estimate that over 90% of near-Earth objects larger than one kilometer have been detected and are being monitored. The NASA NEO survey science definition team (SDT)  determined a cut-off point of 460-foot (140m) whereby impacts from objects of this size would only cause regional effects rather than larger sub-global effects.  A not so comforting statistic is that less than 50% of these objects have been discovered based on the estimated population of asteroids of this size.    


The post ‘Tunguska’ Size Asteroid Buzzes Earth appeared first on Comet Watch.


2018 August 24 Messier 20 and 21 Image Credit & Copyright:…


2018 August 24


Messier 20 and 21
Image Credit & Copyright: Ignacio Diaz Bobillo


Explanation: The beautiful Trifid Nebula, also known as Messier 20, is easy to find with a small telescope in the nebula rich constellation Sagittarius. About 5,000 light-years away, the colorful study in cosmic contrasts shares this well-composed, nearly 1 degree wide field with open star cluster Messier 21 (bottom right). Trisected by dust lanes the Trifid itself is about 40 light-years across and a mere 300,000 years old. That makes it one of the youngest star forming regions in our sky, with newborn and embryonic stars embedded in its natal dust and gas clouds. Estimates of the distance to open star cluster M21 are similar to M20’s, but though they share this gorgeous telescopic skyscape there is no apparent connection between the two. In fact, M21’s stars are much older, about 8 million years old.


∞ Source: apod.nasa.gov/apod/ap180824.html


NASA Analyzes a Solid Ring of Cold Cloud Tops In Hurricane Lane


NASA – EOS Terra Mission patch.


Aug. 23, 2018


Lane – Formerly 14E (Eastern Pacific)


An infrared look by NASA’s Terra satellite provided forecasters with temperature data in the Category 4 hurricane near Hawaii. Terra data showed a large ring of coldest and most powerful storms around Hurricane Lane’s eye on Aug. 23.



Image above: On Aug. 23 at 4:15 a.m. EDT (0815 UTC) NASA’s Terra satellite found the coldest temperatures of the strongest thunderstorms (yellow) in Hurricane Lane were as cold as or colder than minus 80 degrees Fahrenheit (minus 62.2 Celsius) northeast and southwest of the eye. They were embedded in a large area of storms (red) that circled the eye where cloud top temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius). Image Credits: NRL/NASA.


NOAA’s Central Pacific Hurricane Center or CPHC noted that a Hurricane Warning is in effect for Oahu, Maui County including the islands of Maui, Lanai, Molokai and Kahoolawe and Hawaii County. A Hurricane Watch is in effect for Kauai County, including the islands of Kauai and Niiha.


On Aug. 23 at 4:15 a.m. EDT (0815 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Terra satellite analyzed cloud top temperatures in infrared light. MODIS found cloud top temperatures of the strongest thunderstorms northeast and southwest of the eye were as cold as or colder than minus 80 degrees Fahrenheit (minus 62.2 Celsius). They were embedded in a large area or storms that circled the eye where cloud top temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius).


Cloud top temperatures that cold indicate strong storms that have the capability to create heavy rain. Rainfall is expected to be the biggest threat from Lane.


CPHC said, “The cloud-filled eye continues to be surrounded by a solid ring of cold cloud tops, with lightning bursts persisting in the northern eye wall for the last several hours.”


CPHC also noted, “Excessive rainfall associated with Lane will impact the Hawaiian Islands into the weekend, leading to significant and life-threatening flash flooding and landslides. Lane is expected to produce total rain accumulations of 10 to 20 inches, with localized amounts in excess of 30 inches over the Hawaiian Islands.”



NASA’s Terra satellite. Image Credit: NASA

At 8 a.m. EDT (2 a.m. HST/1200 UTC) on Aug. 23, the eye of Hurricane Lane was located by satellite and radar near latitude 16.5 degrees north and longitude 157.3 degrees west.


NOAA’s CPHC said, “Lane is moving toward the northwest near 7 mph (11 kph). This general motion is expected to continue today, with a gradual turn toward the north-northwest. On Friday, a turn toward the north is anticipated as Lane’s forward motion slows even more. A turn back toward the west is expected on Saturday. On the forecast track, the center of Lane will move very close to or over the main Hawaiian Islands later today through Friday (Aug. 24).”


Maximum sustained winds are near 130 mph (215 kph) with higher gusts.  Hurricane-force winds extend outward up to 40 miles (65 km) from the center and tropical-storm-force winds extend outward up to 140 miles (220 km).


Lane is a powerful category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale.


CPHC said, “Some weakening is forecast during the next day or so, with more significant weakening thereafter. Lane is expected to remain a hurricane as it approaches the islands.”


Related articles:


NASA Stares Major Hurricane Lane in the Eye
https://orbiterchspacenews.blogspot.com/2018/08/nasa-stares-major-hurricane-lane-in-eye.html


NASA & JAXA GPM Satellite Finds Heavy Rainfall in Powerful Hurricane Lane
https://orbiterchspacenews.blogspot.com/2018/08/nasa-jaxa-gpm-satellite-finds-heavy.html


For updated forecasts, visit: http://www.prh.noaa.gov/cphc


NASA’s Terra satellite: https://terra.nasa.gov/


Images (mentioned), Text, Credits: NASA’s Goddard Space Flight Center, by Rob Gutro.


Greetings, Orbiter.chArchive link


Global Cargo Missions Planned as Critical Research Proceeds


ISS – Expedition 56 Mission patch.


August 23, 2018


A Russian cargo ship departed the International Space Station Wednesday night as another resupply mission from Japan is planned in September. The Expedition 56 crew members also observed protein crystals, studied an ancient navigation technique and researched time perception in space.


Two Soyuz crew ships and a Progress resupply ship remain docked at the orbital lab after the Progress 69 (69P) cargo craft undocked from the Zvezda service module Wednesday at 10:16 p.m. EDT. It will orbit Earth until Aug. 29 for engineering tests monitored by Roscosmos mission controllers before deorbiting over the Pacific Ocean.



Image above: Russia’s two docked spacecraft, the Soyuz MS-09 (left) crew ship and the Progress 70 resupply ship, are pictured as the International Space Station orbited nearly 254 miles above northern Kazakhstan. Image Credit: NASA.


The next resupply mission is coming from the Japan Aerospace Exploration Agency’s “Kounotori” H-II Transfer Vehicle. It is targeted for launch Sept. 10 to deliver science, supplies and batteries for installation during a pair of spacewalks next month. Russia’s next resupply mission, the Progress 71, is targeted for a two-day trip to the station at the end of October.


Commander Drew Feustel continued working on a pair of similar protein crystal experiments today. The BioServe Protein Crystalography-1 and Protein Crystal Growth-13 studies allow astronauts to observe crystal growth in space and analyze the results. This saves researchers time without having to wait for samples to be returned to Earth for analysis.



International Space Station (ISS). Image Credit: NASA

Alexander Gerst of ESA assisted Serena Auñón-Chancellor from NASA and tested using a sextant in space for celestial navigation during an emergency. The duo worked inside the Cupola today and tested stability, positioning and sighting with the device using a star map.


Gerst then switched his attention to a European Space Agency study exploring how astronauts perceive time in space. Researchers seek to quantify subjective changes in time perception to understand how astronauts navigate, move and hear in space.


Related links:


Expedition 56: https://www.nasa.gov/mission_pages/station/expeditions/expedition56/index.html


Spacewalks: http://www.nasa.gov/mission_pages/station/spacewalks


BioServe Protein Crystalography-1: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7729


Protein Crystal Growth-13: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7690


Sextant in space: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7646


Perceive time in space: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7504


Roscosmos: http://en.roscosmos.ru/


Japan Aerospace Exploration Agency (JAXA): http://global.jaxa.jp/projects/iss_human/index.html


European Space Agency (ESA): https://www.esa.int/Our_Activities/Human_Spaceflight


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


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


Greetings, Orbiter.chArchive link


Tomnavrie Recumbent Stone Circle, Tarland, Aberdeenshire, Scotland, 17.8.18.











Tomnavrie Recumbent Stone Circle, Tarland, Aberdeenshire, Scotland, 17.8.18.


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ALPHA experiment takes antimatter to a new level


CERN – European Organization for Nuclear Research logo.


August 23, 2018


In a paper published today in the journal Nature, the ALPHA collaboration reports that it has literally taken antimatter to a new level. The researchers have observed the Lyman-alpha electronic transition in the antihydrogen atom, the antimatter counterpart of hydrogen, for the first time. The finding comes hot on the heels of recent measurements by the collaboration of another electronic transition, and demonstrates that ALPHA is quickly and steadily paving the way for precision experiments that could uncover as yet unseen differences between the behaviour of matter and antimatter.



Image above: Jeffrey Hangst, spokesperson for the ALPHA experiment, next to the experiment. (Image: Maximilien Brice, Julien Ordan/CERN).


The Lyman-alpha (or 1S-2P) transition is one of several in the Lyman series of electronic transitions that were discovered in atomic hydrogen just over a century ago by physicist Theodore Lyman. The transition occurs when an electron jumps from the lowest-energy (1S) level to a higher-energy (2P) level and then falls back to the 1S level by emitting a photon at a wavelength of 121.6 nanometres.


It is a special transition. In astronomy, it allows researchers to probe the state of the medium that lies between galaxies and test models of the cosmos. In antimatter studies, it could enable precision measurements of how antihydrogen responds to light and gravity. Finding any slight difference between the behaviour of antimatter and matter would rock the foundations of the Standard Model of particle physics and perhaps cast light on why the universe is made up almost entirely of matter, even though equal amounts of antimatter should have been produced in the Big Bang.


The ALPHA team makes antihydrogen atoms by taking antiprotons from CERN’s Antiproton Decelerator (AD) and binding them with positrons from a sodium-22 source. It then confines the resulting antihydrogen atoms in a magnetic trap, which prevents them from coming into contact with matter and annihilating. Laser light is then shone onto the trapped atoms to measure their spectral response. The measurement involves using a range of laser frequencies and counting the number of atoms that drop out of the trap as a result of interactions between the laser and the trapped atoms.


The ALPHA collaboration has previously employed this technique to measure the so-called 1S-2S transition. Using the same approach and a series of laser wavelengths around 121.6 nanometres, ALPHA has now detected the Lyman-alpha transition in antihydrogen and measured its frequency with a precision of a few parts in a hundred million, obtaining good agreement with the equivalent transition in hydrogen.


This precision is not as high as that achieved in hydrogen, but the finding represents a pivotal technological step towards using the Lyman-alpha transition to chill large samples of antihydrogen using a technique known as laser cooling. Such samples would allow researchers to bring the precision of this and other measurements of antihydrogen to a level at which any differences between the behaviour of antihydrogen and hydrogen might emerge.


“We are really excited about this result,” says Jeffrey Hangst, spokesperson for the ALPHA experiment. “The Lyman-alpha transition is notoriously difficult to probe – even in ‘normal’ hydrogen. But by exploiting our ability to trap and hold large numbers of antihydrogen atoms for several hours, and using a pulsed source of Lyman-alpha laser light, we were able to observe this transition. Next up is laser cooling, which will be a game-changer for precision spectroscopy and gravitational measurements.”


Note:


CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.


The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.


Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.


Related links:


Journal Nature: http://dx.doi.org/10.1038/s41586-018-0435-1


Standard Model of particle physics: https://home.cern/about/physics/standard-model


CERN’s Antiproton Decelerator (AD): https://home.cern/about/accelerators/antiproton-decelerator


ALPHA: http://alpha.web.cern.ch/


For more information about European Organization for Nuclear Research (CERN), Visit: https://home.cern/


Image (mentioned), Text, Credits: CERN/Ana Lopes.


Best regards, Orbiter.chArchive link


15 Years in Space for NASA’s Spitzer Space Telescope


NASA – Spitzer Space Telescope patch.


Aug. 23, 2018



Image above: This image shows an artist’s impression of the Spitzer Space Telescope. The background shows an infrared image from Spitzer of the plane of the Milky Way galaxy. Image Credits: NASA/JPL.


Initially scheduled for a minimum 2.5-year primary mission, NASA’s Spitzer Space Telescope has gone far beyond its expected lifetime — and is still going strong after 15 years.


Launched into a solar orbit on Aug. 25, 2003, Spitzer was the final of NASA’s four Great Observatories to reach space. The space telescope has illuminated some of the oldest galaxies in the universe, revealed a new ring around Saturn, and peered through shrouds of dust to study newborn stars and black holes. Spitzer assisted in the discovery of planets beyond our solar system, including the detection of seven Earth-size planets orbiting the star TRAPPIST-1, among other accomplishments.


“In its 15 years of operations, Spitzer has opened our eyes to new ways of viewing the universe,” said Paul Hertz, director of the Astrophysics Division at NASA Headquarters in Washington. “Spitzer’s discoveries extend from our own planetary backyard, to planets around other stars, to the far reaches of the universe. And by working in collaboration with NASA’s other Great Observatories, Spitzer has helped scientists gain a more complete picture of many cosmic phenomena.”



Image above: This artist’s impression shows what the seven Earth-size planets of the TRAPPIST-1 system might look like, based on available data. No actual images of the planets exist. Image Credits: NASA/JPL-Caltech.


A view into the past


Spitzer detects infrared light — most often heat radiation emitted by warm objects. On Earth, infrared light is used in a variety of applications, including night-vision instruments.


With its infrared vision and high sensitivity, Spitzer has contributed to the study of some of the most distant galaxies in the known universe. The light from some of those galaxies traveled for 13.4 billion years to reach Earth. As a result, scientists see these galaxies as they were less than 400 million years after the birth of the universe.


Among this population of ancient galaxies was a surprise for scientists: “big baby” galaxies that were much larger and more mature than scientists thought early-forming galaxies could be. Large, modern galaxies are thought to have formed through the gradual merger of smaller galaxies. But the “big baby” galaxies showed that massive collections of stars came together very early in the universe’s history.


Studies of these very distant galaxies relied on data from both Spitzer and the Hubble Space Telescope, another one of NASA’s Great Observatories. Each of the four Great Observatories collects light in a different wavelength range. By combining their observations of various objects and regions, scientists can gain a more complete picture of the universe.


“The Great Observatories program was really a brilliant concept,” said Michael Werner, Spitzer project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California. “The idea of getting multispectral images or data on astrophysical phenomenon is very compelling, because most heavenly bodies produce radiation across the spectrum. An average galaxy like our own Milky Way, for example, radiates as much infrared light as visible wavelength light. Each part of the spectrum provides new information.”


New worlds


In recent years, scientists have utilized Spitzer to study exoplanets, or planets orbiting stars other than our Sun, although this was not something the telescope’s designers anticipated.


With Spitzer’s help, researchers have studied planets with surfaces as hot as stars, others thought to be frozen solid, and many in between. Spitzer has studied some of the nearest known exoplanets to Earth, and some of the most distant exoplanets ever discovered.


Spitzer also played a key role in one of the most significant exoplanet discoveries in history: the detection of seven, roughly Earth-size planets orbiting a single star. The TRAPPIST-1 planetary system was unlike any alien solar system ever discovered, with three of its seven planets located in the “habitable zone,” where the temperature might be right for liquid water to exist on the planets’ surfaces. Their discovery was an enticing step in the search for life elsewhere in the universe.


“The study of extrasolar planets was still in its infancy when Spitzer launched, but in recent years, often more than half of Spitzer’s observation time is used for studies of exoplanets or searches for exoplanets,” said Lisa Storrie-Lombardi, Spitzer’s project manager at JPL. “Spitzer is very good at characterizing exoplanets, even though it wasn’t designed to do that.”





Image above: A major part of Spitzer’s scientific legacy has been the study of very distant objects in the universe. Scientists combined the power of NASA’s Spitzer and Hubble space telescopes to study a multitude of extremely distant galaxies. The objects circled in white are galaxies that belong to an emerging galaxy cluster. This proto-cluster is one of the most distant ever identified. Image Credits: Subaru/NASA/JPL-Caltech.


Some other major discoveries made using the Spitzer space telescope include:


— The largest known ring around Saturn, a wispy, fine structure with 300 times the diameter of Saturn. http://www.jpl.nasa.gov/news/news.php?release=2009-150


— First exoplanet weather map of temperature variations over the surface of a gas exoplanet. Results suggested the presence of fierce winds. http://www.jpl.nasa.gov/news/news.php?release=2007-055


— Asteroid and planetary smashups. Spitzer has found evidence for several rocky collisions in other solar systems, including one thought to involve two large asteroids. http://www.jpl.nasa.gov/news/news.php?release=2014-291


— Recipe for “comet soup.” Spitzer observed the aftermath of the collision between NASA’s Deep Impact spacecraft and comet Tempel 1, finding that cometary material in our own solar system resembles that around nearby stars. http://www.jpl.nasa.gov/news/news.php?release=2005-144


— The hidden lairs of newborn stars. Spitzer’s infrared images have provided unprecedented views into the hidden cradles where young stars grow up, revolutionizing our understanding of stellar birth. http://www.jpl.nasa.gov/news/news.php?release=2008-023


— Buckyballs in space. Buckyballs are soccer-ball-shaped carbon molecules   discovered in laboratory research with multiple technological applications on Earth.. http://www.jpl.nasa.gov/news/news.php?feature=2679


— Massive clusters of galaxies. Spitzer has identified many more distant galaxy clusters than were previously known. http://www.jpl.nasa.gov/news/news.php?feature=2875


— One of the most extensive maps of the Milky Way galaxy ever compiled, including the most accurate map of the large bar of stars in the galaxy’s center, created using Spitzer data from the Galactic Legacy Mid-Plane Survey Extraordinaire project, or GLIMPSE. https://www.jpl.nasa.gov/news/news.php?feature=4085




Image above: Newborn stars peek out from beneath their natal blanket of dust in this dynamic image of the Rho Ophiuchi dark cloud from NASA’s Spitzer Space Telescope. Spitzer observes infrared light, which in most cases can penetrate gas and dust clouds better than visible light. Image Credits: NASA/JPL-Caltech/Harvard-Smithsonian CfA.


An extended journey


Spitzer has logged over 106,000 hours of observation time. Thousands of scientists around the world have utilized Spitzer data in their studies, and Spitzer data is cited in more than 8,000 published papers.


Spitzer’s primary mission ended up lasting 5.5 years, during which time the spacecraft operated in a “cold phase,” with a supply of liquid helium cooling three onboard instruments to just above absolute zero. The cooling system reduced excess heat from the instruments themselves that could contaminate their observations. This gave Spitzer very high sensitivity for “cold” objects.


In July 2009, after Spitzer’s helium supply ran out, the spacecraft entered a so-called “warm phase.” Spitzer’s main instrument, called the Infrared Array Camera (IRAC), has four cameras, two of which continue to operate in the warm phase with the same sensitivity they maintained during the cold phase.


Spitzer orbits the Sun in an Earth-trailing orbit (meaning it literally trails behind Earth as the planet orbits the Sun) and has continued to fall farther and farther behind Earth during its lifetime. This now poses a challenge for the spacecraft, because while it is downloading data to Earth, its solar panels do not directly face the Sun. As a result, Spitzer must use battery power during data downloads. The batteries are then recharged between downloads.


“Spitzer is farther away from Earth than we ever thought it would be while still operating,” said Sean Carey, manager of the Spitzer Science Center at Caltech in Pasadena, California. “This has posed some real challenges to the engineering team, and they’ve been extremely creative and resourceful to keep Spitzer operating far beyond its expected lifetime.”


In 2016, Spitzer entered an extended mission dubbed “Spitzer Beyond.” The spacecraft is currently scheduled to continue operations into November 2019, more than 10 years after entering its warm phase.


In celebration of Spitzer’s 15 years in space, NASA has released two new multimedia products: The NASA Selfies app for iOS and Android, and the Exoplanet Excursions VR Experience for Oculus and Vive, as well as a 360-video version for smartphones. Spitzer’s incredible discoveries and amazing images are at the center of these new products.


JPL manages the Spitzer Space Telescope mission for NASA’s Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech in Pasadena, California. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at the IPAC at Caltech. Caltech manages JPL for NASA. For more information about Spitzer, visit:


https://spitzer.caltech.edu


https://www.nasa.gov/spitzer


Images (mentioned), Text, Credits: NASA/Tony Greicius/JPL/Calla Cofield.


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East Aquhorthies Recumbent Stone Circle, Aberdeenshire, Scotland, 18.8.18.


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