среда, 3 апреля 2019 г.

Which came first, the lizard or the egg?

In a world first, researchers at the University of Sydney have observed a normally live-bearing Australian lizard lay three eggs and then weeks later, give birth to a live baby from the same pregnancy. This is the first time such an event has been documented in a single litter of vertebrate babies.











Which came first, the lizard or the egg?
Three-toed skink hatching from an egg [Credit: Nadav Pezaro,
Haifa University for the University of Sydney]

The three-toed skink (Saiphos equalis) is one of only a handful of rare “bimodally reproductive” species, in which some individuals lay eggs and others give birth to live babies. But up until now, no vertebrate has ever been observed to do both in one litter.


“It is a very unusual discovery,” said Dr Camilla Whittington, from the School of Life and Environmental Sciences and Sydney School of Veterinary Science at the University of Sydney.


The three-toed skink is native to the east coast of Australia. In the northern highlands of New South Wales the animals normally give birth to live young, but those living in and around Sydney lay eggs.


“We were studying the genetics of these skinks when we noticed one of the live-bearing females lay three eggs,” Dr Whittington said. “Several weeks later she gave birth to another baby. Seeing that baby was a very exciting moment!”


The observation will be published in Biology Letters this week, along with advanced microscopy of the egg-coverings.











Which came first, the lizard or the egg?
Siphos adult [Credit: University of Sydney]

There are at least 150 evolutionary transitions from egg-laying to live-bearing in vertebrates said Dr Whittington, who led the study alongside Dr Melanie Laird, a postdoctoral researcher at the University of Otago, and Emeritus Professor Mike Thompson.


“The earliest vertebrates were egg-layers, but over thousands of years, developing embryos in some species were held inside the body for longer, until some animals began to give live birth. People mostly think about humans and other mammals giving birth. But there are many species of reptile that give birth, too.”


Dr Whittington said that the unusual observation of both egg laying and live birth in a single litter shows that the three-toed skink is an ideal model for understanding pregnancy. “It makes Australia one of the best places in the world to study the evolution of live birth, because we can watch evolution in action,” she said.


“Put in the context of evolutionary biology, being able to switch between laying eggs and giving live birth could allow animals to hedge their bets according to environmental conditions,” Dr Whittington said.


This observation helps make the three-toed skink, which looks like a baby snake with tiny legs, one of the “weirdest lizards in the world”, she said.


Further research into this small lizard, which seems to occupy a grey area between live birth and egg-laying, will help determine how and why species make major reproductive leaps.


Source: University of Sydney [April 02, 2019]



TANN



Archive


Prebiotic chemistry: Stable majorities

How could prebiotic information-bearing DNA sequences survive in the face of competition from a vast excess of shorter molecules with random sequences? Ludwig-Maximilians-Universitaet (LMU) in Munich scientists now show that a relatively simple mechanism could have done the trick.











Prebiotic chemistry: Stable majorities
Rifted rocks riddled with water-filled pores and steep temperature gradients: Prebiotic informational
biomolecules could have been formed in such a setting at the dawn of life
[Credit: Dieter Braun]

Life is a matter of energy – and information ­- lots of information – more specifically, the hereditary information stored in the DNA that is present in all living cells. Thus the coding capacity of the nuclear DNA found in every mammalian cell is equivalent to some 700 Mbyte. This information has accumulated and been successfully transmitted over billions of years of evolution. For researchers like Dieter Braun (Professor of Systems Biophysics at LMU) who are interested in understanding how life on Earth originated, one of the many questions this raises is how the very first informational molecules that were formed under prebiotic conditions could have outcompeted their many rivals with much smaller information content.
In collaboration with his colleague Professor Shoichi Toyabe of Tohoku University in Sendai (Japan), who has already made many working visits to his laboratory, Braun now reports a set of experiments and simulations which suggests that quite a simple mechanism can in principle resolve the paradox, and could have enabled primordial informational sequences to survive. That in turn implies that any useful genetic information which happened to be encoded in such sequences need not have vanished (like the myriads of random sequences) back into the chaos from which they arose, or been progressively fragmented into shorter and shorter molecules (which most models of the primordial soup indicate were most likely to be replicated) and essentially diluted out.


The templated ligation mechanism proposed by Braun and Toyabe is a well-known molecular genetic process in modern-day cells. When two single-stranded DNA molecules bind to adjacent regions of a longer strand (the template), the two can easily be connected to one another (ligated) by the same kind of mechanism that first gave rise to them. “As long as this simple mechanism is available under the prevailing reaction conditions, compatible DNA segments can be selected from a random mixture of sequences and brought into a position which allows them to be linked together to create a longer strand,” Braun explains.


In this way, depending on the relative concentrations of the complementary sequences, the stage is set for intermolecular cooperation. Higher temperatures and steep temperature gradients – like those that are thought to have characterized the narrow, water-filled pores in volcanic rocks in which primordial DNA synthesis may have occurred – promote the stringing together of shorter molecules into longer sequences. This would allow faster selection, elongation and subsequent replication of longer molecules. In other words, templated ligation can create stable majorities by promoting the assembly and replication of sequences that are complex enough to encode the first genetic information. For the authors of the new paper, “these cooperative ligation networks provide an example of symmetry breaking, a well-known mechanism of structure formation in physics,” says Braun.


In the 1970s, Manfred Eigen (Nobel Prize for Chemistry 1967) and Peter Schuster developed their ‘hypercycle’ model as a theoretically feasible pathway from the earliest prebiotic DNA sequences to the stable transmission of genetic information. However, they lacked an experimentally tractable system that would allow them to mimic prebiotic conditions in a more-or-less realistic fashion. “Our experimental contributions demonstrate, that it is possible to obtain the required stable majorities of informational sequences in the primordial soup using the simplest of methods,” Braun concludes.


The study is published in Physical Review X.


Source: Ludwig-Maximilians-Universität München [April 02, 2019]



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Archive


Origin of the saffron crocus traced back to Greece

The origin of C. sativus has long been the subject of speculation and research, as this knowledge would enable breeders to introduce genetic diversity into the otherwise genetically uniform plant species. Two new studies have now shown that the saffron crocus originated from a Greek ancestor.











Origin of the saffron crocus traced back to Greece
Crocus cartwrightianus [Credit: Frank Blattner/IPK]

Since ancient times, saffron has been giving dishes a golden-yellow hue and an aromatic flavour. The use of the stigmas of the saffron crocus (Crocus sativus) is depicted in frescos from Crete and Santorini, which are as old as 3600 years. Nowadays, the valuable plant is mainly cultivated in Iran accounting for more than 90% of the saffron production.


Due to its hardiness, small batches of the saffron crocus are even grown and harvested in more unlikely countries such as Switzerland and Germany. Possibly partially due to its widespread agricultural adoption, the origin of saffron has until recently been a subject of speculation. Now, a study published in Molecular Phylogenetics and Evolution has been able to trace the roots of C. sativus back to Greece.


The saffron crocus is a triploid and male-sterile plant. This means that the plant can only be propagated vegetatively. In this case, parts of the corms (bulb-like structures of the stem) of the saffron plants are broken off and then these daughter-corms are used to grow new adult plants.


A consequence of this form of reproduction is that there is no room for improving saffron quality by crossing different cultivars. Thus all modern saffron plants are genetically nearly identical. Knowing the origin, in particular the originating plant species, would enable saffron breeders to use new genotypes to broaden the diversity of the saffron crocus.











Origin of the saffron crocus traced back to Greece
Map providing the distribution area of Crocus cartwrightianus (dashed line). In red the Attica region
is depicted where the saffron crocus originated [Credit: Frank Blattner]

Researchers of the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK Gatersleben) decided to tackle the mystery of saffron’s origin, by comparing molecular markers of wild crocus species with those of our cultivated saffron crocus. In the research group of Frank Blattner, plant material was obtained through sample-collecting excursions from native stands of all relevant species.


Through the analyses of genome-wide single-nucleotide polymorphisms (SNPs) and the investigation of the chloroplast genomes of the different crocus species, the researchers were able to pinpoint the species with the highest genetic similarity to C. sativus. As such, the wild crocus species C. cartwrightianus from Greece was identified as the sole progenitor of the modern saffron plant, and the area in the vicinity of the Greek capital Athens as the region where it evolved.


C. cartwrightianus had already been postulated as a possible progenitor of C. sativus, however the high intra-specific genetic diversity present in C. cartwrightianus had led to unclear results during previous investigations. Now, in the IPK-study, an unambiguous total of 99.3% of the alleles of C. sativus could be recovered in C. cartwrightianus.


These results were confirmed by an independent complementary study performed by researchers at TU Dresden. The Dresden scientists in Thomas Schmidt’s group performed comparative chromosome analysis with fluorescence in situ hybridization (FISH) of different crocus species, and could also demonstrate that C. sativus resulted from the fusion of the genomes of two C. cartwrightianus plants, an event called “autopolyploidisation”.


A slight surprise for all of the involved researchers was that the main growing regions for saffron are clearly located outside the distribution area of its progenitor C. cartwrightianus, with C. sativus prospering in drier regions and at higher elevations. They suspect that the explanation to this also lies within the origin story of saffron – it was probably the genome-fusing autopolyploidisation event that led to ecological shift of saffron, away from the habitats in the Mediterranean vegetation zone of Greece.


Source: Leibniz Institute of Plant Genetics and Crop Plant Research [April 02, 2019]



TANN



Archive


Permian volcanism contributed to atmospheric greenhouse gas content in Antarctica

The Choiyoi magmatic Province, with an estimated volume of ~1.3 million square kilometers, represents a voluminous Permian subduction-related volcanic episode that has thus far been described only from South America. In their new paper for Lithosphere, Demian Nelson and John Cottle investigated Permian volcaniclastic rocks from central Antarctica to determine the potential magmatic source of volcanic detritus in southwestern Gondwana.











Permian volcanism contributed to atmospheric greenhouse gas content in Antarctica
Credit: MIT

Permian volcanic deposits are and record voluminous silicic continental arc that may have contributed to Permian global warming and environmental degradation. Nelson and Cottle present new age and in-situ Hf isotopic data from the mineral zircon greatly expand the known distribution of Choiyoi-related deposits and highlight the importance of voluminous subduction-related volcanism, termed “arc flare-up” events, that may contribute a first-order control on atmospheric greenhouse gas contents.


For instance, the Permian period contained one of the most severe environmental degradation and mass extinction events in Earth’s history. Climate change and biotic crises during this time have been attributed to the massive release of greenhouse gases during Large Igneous Province eruptions (e.g., the Siberian Traps and Mishna).


These new age data for the Choiyoi Province correlate with a global increase in arc magmatic flux, a decrease in delta-13C, and an increase in global atmospheric CO2 that began prior to emplacement of the Siberian Traps.


Consequently, these findings support recent advancements in the field that point to arc flare-up events as contributing a first-order control on atmospheric greenhouse gas content. Major environmental degradation and mass extinction events, ultimately, may have been the result of high magmatic flux events, such as the Choiyoi Province occurring synchronously, or near synchronously, with a Large Igneous Province event, such as the Siberian Traps or the Mishna.


This finding represents the southernmost documented extension of this broad volcanic and magmatic province that is distinct from continental arc activity recorded in the central Transantarctic mountains, Marie Byrd Land, Zealandia, and Australia.


Source: Geological Society of America [April 02, 2019]



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Gun that Van Gogh killed himself with goes up for auction

The revolver with which Vincent Van Gogh is believed to have shot himself is to go under the hammer, a Paris auction house said Tuesday.











Gun that Van Gogh killed himself with goes up for auction
‘Portrait de l’Artiste’, Autumn 1887, a self-portrait by Vincent van Gogh, at the exhibition ‘Van Gogh/
Artaud The Man Suicided by Society’, Musee d’Orsay, Paris March 10, 2014 [Credit: Reuters]

Discovered by a farmer in 1965 in the same field where the troubled Dutch painter is thought to have fatally wounded himself 75 years before, the gun has already been exhibited at the Van Gogh Museum in Amsterdam.


Billed by Auction Art as “the most famous weapon in the history of art”, the 7 mm Lefaucheux revolver is expected to go for up to 60,000 euros ($67,000) when it is sold on June 19.


Van Gogh experts believe that he shot himself with the revolver near the village of Auvers-sur-Oise north of Paris, where he spent the last few months of his life in 1890.


The Dutch artist had borrowed the gun from the owner of the inn where he was staying. He died 36 hours later after staggering wounded back to the inn in the dark.


It was not his first dramatic act of self-harm. Two years earlier in 1888, he cut off his ear before offering it to a woman in a brothel in Arles in the south of France.


While most art historians agree that Van Gogh killed himself, that assumption has been questioned in recent years, with some researchers claiming that the fatal shot may have been fired accidentally by two local boys playing with the weapon in the field.











Gun that Van Gogh killed himself with goes up for auction
The revolver which the Dutch painter Vincent van Gogh supposedly used to kill himself is displayed as part of the
exhibition ‘On the Verge of Insanity: Van Gogh and his Illness’ at the Van Gogh Museum in Amsterdam,
The Netherlands, 2016 [Credit: Robin van Lonkhuijsen/EPA]

That theory got fresh support from a new biopic of the artist starring Willem Dafoe, “At Eternity’s Gate”.


Its director, the renowned American painter Julian Schnabel, told AFP that Van Gogh had painted 75 canvasses in his 80 days at Auvers-sur-Oise and was unlikely to be suicidal.


The legendary French screenwriter Jean-Claude Carriere — who co-wrote the script with Schnabel — insisted that there “is absolutely no proof he killed himself.


“Do I believe that Van Gogh killed himself? Absolutely not!” he declared when the film was premiered at the Venice film festival in September.


He said Van Gogh painted some of his best work in his final days, including his “Portrait of Dr Gachet”, the local doctor who later tried to save his life.


It set a world record when it sold for $82.5 million in 1990.


The bullet Dr Gachet extracted from Van Gogh’s chest was the same calibre as the one used by the Lefaucheux revolver.











Gun that Van Gogh killed himself with goes up for auction
The revolver Vincent Van Gogh is believed to have shot himself with was found in a field by farmer in 1965,
75 years after the painter’s death [Credit: AFP/Bart Maat]

“Van Gogh was working constantly. Every day he made a new work. He was not at all sad,” Carriere argued.


In the film the gun goes off after the two young boys, who were brothers, got into a struggle with the bohemian stranger.


Auction Art said that the farmer who found the gun in 1965 gave it to the owners of the inn at Auvers-sur-Oise, whose family are now selling it.


“Technical tests on the weapon have shown the weapon was used and indicate that it stayed in the ground for a period that would coincide with 1890,” it said.


“All these clues give credence to the theory that this is the weapon used in the suicide.”


That did not exclude, the auction house added, that the gun could not also have been hidden or abandoned by the two young brothers in the field.


Author: Fiachra Gibbons & Jean-François Guyot | Source: AFP [April 02, 2019]



TANN



Archive


A 5,000-year-old barley grain discovered in Finland

On the basis of prior research, representatives of the Pitted Ware Culture from the Stone Age have been known as hard-core sealers, or even Inuits of the Baltic Sea. Now, researchers have discovered barley and wheat grains in areas previously inhabited by this culture, leading to the conclusion that the Pitted Ware Culture adopted agriculture on a small scale.











A 5,000-year-old barley grain discovered in Finland
Researchers determined the age of millennia-old barley grains using radiocarbon dating
[Credit: Santeri Vanhanen]

A study carried out in cooperation with parties representing the discipline of archaeology and the Department of Chemistry at the University of Helsinki, as well as Swedish operators in the field of archaeology (The Archaeologists, a governmental consultant agency, and Arkeologikonsult, a business), found grains of barley and wheat in Pitted Ware settlements on Finland’s Aland Islands and in the region of modern Stockholm.


The age of the grains was ascertained using radiocarbon dating. Based on the results, the grains originated in the period of the Pitted Ware culture, thus being approximately 4,300-5,300 years old. In addition to the cereal grains, the plant remnants found in the sites included hazelnut shells, apple seeds, tuberous roots of lesser celandine and rose hips.


The study suggests that small-scale farming was adopted by the Pitted Ware Culture by learning the trade from farmers of the Funnel Beaker Culture, the latter having expanded from continental Europe to Scandinavia. Other archaeological artefacts are also evidence of close contact between these two cultures.


“The grains found on Aland are proof that the Pitted Ware Culture introduced cultivation to places where it had not yet been practised,” says Santeri Vanhanen, a doctoral student of archaeology at the University of Helsinki.











A 5,000-year-old barley grain discovered in Finland
Archaeological finds. (a) Excavation plan of the Glamilders site, showing distributions of selected cultural layers,
post-holes, and hearths organized in a SW-NE direction. Soil samples were taken from the vicinity of the
hearths (sample details in Supplementary Table 5). (b) A grinding stone found in a post-hole
 in Glamilders. (c) Hearth 1 from Glamilders, measuring 1.5 × 0.8 metres
[Credit: Santeri Vanhanen et al. 2019]

The 5,000-year-old barley grain found on Aland is the oldest grain of cereal ever found in Finland. The researchers also found a handful of barley and wheat grains a few hundred years younger, representing either common wheat or club wheat.


“We also dated one barley grain found in Raseborg, southern Finland. This grain and the other earliest grains found in mainland Finland date back some 3,500 years, some 1,500 years behind Aland according to current knowledge,” Vanhanen explains.


In prior studies, it has been extremely difficult to demonstrate that the hunter-gatherer population would have adopted farming during recorded history, let alone in the Stone Age. Research on ancient DNA has in recent years proven that the spread of agriculture in Europe was almost exclusively down to migrants.


“We find it possible that this population, which was primarily specialised in marine hunting, continued to grow plants as the practice provided the community with social significance.”











A 5,000-year-old barley grain discovered in Finland
In the study, the age of cereal grains found at the sites tagged with numbers in the map were determined with radiocarbon
dating. These findings demonstrate that hunter-gatherers adopted farming on the Åland Islands
on the southwestern coast of Finland and in eastern Sweden already 5,000 years ago
[Credit: Santeri Vanhanen]

From time to time, an abundance of pig bones are found at Pitted Ware sites, even though pigs were not an important part of their daily nourishment. For instance, the bones of more than 30 pigs were found in a grave located on the island of Gotland.


“Members of the Pitted Ware culture may have held ritual feasts where pigs and cereal products were consumed. It’s not inconceivable that grains might even have been used to brew beer, but the evidence is yet to be found,” Vanhanen continues.


The research relies primarily on archaeobotanical methodology, which helps examine plant remains preserved in archaeological sites. In this study, soil samples were collected from the sites, from which plant remains were extracted using a flotation method. The plant remains are charred; in other words, the grains and seeds have turned into carbon after having come to contact with fire.


Plant remains can be identified by examining them through a microscope and comparing them to modern plant parts. The age of individual grains can be determined with radiocarbon dating, based on the fractionation of the radioactive carbon-14 isotope. This way, the age of a grain aged several millennia can be determined with a precision of a few centuries.


The study was published in Scientific Reports.


Source: University of Helsinki [April 03, 2019]



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Archive


CASC – Long March-3B launches TianLian-2 01 satellite


CASC – China Aerospace Science and Technology Corporation logo.


April 3, 2019



Long March-3B rocket carrying TianLian-2 01 satellite launch

A Long March-3B rocket launched the TianLian-2 01 satellite (天链二号01星) from the Xichang Satellite Launch Center, Sichuan Province, southwest China, on 31 March 2019, at 15:51 UTC (23:51 local time).



Long March-3B launches TianLian-2 01 satellite

According to official sources, the satellite entered the desired geosynchronous orbit. TianLian-2 01 is the first satellite of China’s second-generation data relay satellite system.



TL 1A

The TL 1 (Tian Lian 1) satellite is a geostationary relay satellite based on the DFH-3 Bus (three-axis-stabilized telecommunications satellite platform). TL 1 will be used to support real-time communications between orbiting satellites and ground control stations. This system will replace the current network of ground-based space tracking and telemetry stations and space tracking ships.


Images, Video, Text, Credits: CASC/China Central Television (CCTV)/SciNews/Gunter’s Space Page.


Greetings, Orbiter.chArchive link


ISRO – PSLV-QL launches EMISAT and 28 nanosatellites


ISRO – Indian Space Research Organisation logo.


April 3, 2019



PSLV-C45 carrying EMISAT and 28 nanosatellites launch

For ISRO’s PSLV-C45 mission, a Polar Satellite Launch Vehicle (PSLV) in “QL” configuration launched EMISAT (436 kg) and 28 nano satellites (220kg) from the Second Launch Pad (SLP) of Satish Dhawan Space Centre (SDSC) SHAR, Sriharikota, on 1 April 2019, at 03:57 UTC (09:30 IST).



PSLV-QL launches EMISAT and 28 nanosatellites

India’s Polar Satellite Launch Vehicle (PSLV), designated PSLV-C45, will launch the EMISat satellite, reportedly an electronic intelligence-gathering spacecraft for the Indian government.



EMISat

Multiple secondary payloads from international customers, including 20 Dove nanosatellites for Planet, will ride piggyback on this mission. The PSLV will fly in a new configuration with four strap-on solid rocket boosters.


ISRO Press Release: https://www.isro.gov.in/launcher/pslv-c45-emisat-mission


Images, Text, Video, Credits: Indian Space Research Organisation(ISRO)/SciNews.


Greetings, Orbiter.chArchive link


met-egyptian-art: Marsh Bowl, Egyptian Art Purchase, Edward S….


met-egyptian-art:



Marsh Bowl, Egyptian Art


Purchase, Edward S. Harkness Gift, 1926

Metropolitan Museum of Art, New York, NY
Medium: Faience


http://www.metmuseum.org/art/collection/search/547609



Source


inthemarshes: grandegyptianmuseum: Relief depicting Anubis as a…


inthemarshes:



grandegyptianmuseum:



Relief depicting Anubis as a Roman legionary preparing the mummy of the deceased, 2nd century AD. Catacombs of Kom El Shoqafa.


Archaeological site located in Alexandria, Egypt and is considered one of the Seven Wonders of the Middle Ages. Merges Greek, Roman and Egyptian iconography.



Notice also Horus holding up burning resin in a censer to the left and the canopic jars under the lion “bed” wearing Osiris’ two plume white crown – emphasizing the connection to Osiris – and the feather of Ma’at held by the front claw of the lion. On the right side stands Djehuty holding an ointment jar (only the tip of His beak and the ointment jar is visible on this picture).



Source


thehereticpharaoh: The Sarcophagus of Sha-Amun-em-su, a singer…




thehereticpharaoh:



The Sarcophagus of Sha-Amun-em-su, a singer priestess of the Temple of Amun in Thebes, in ancient Egypt during the 8th century B.C.E.


This sarcophagus was a present offered by the Khedive of Egypt Ismail to the Emperor of Brazil D. Pedro II when he visited Egypt in 1876. D. Pedro II kept it standing upright in his study, near a window. When winds forced the window open one day, the coffin was hit by a window-catch, breaking part of its side. Its left side was then repaired; this feature was still visible today.


The feminine face was painted to resemble natural skin color. The blue wig is decorated with yellow vulture wings and yellow and red bands. The decoration was largely executed in dark green, red, and yellow on a white background. A ram-headed bird extends its wings across the lid as a sign of protection. Two uraei, one with the Crown of Upper Egypt and one with that of Lower Egypt, flank the talons and tail of the bird. Opposite each serpent stand two Sons of Horus. On the right is Imset, with a human head, and Hapy, with the head of a baboon. On the left, Duamutef (with the head of a jackal) and Qebehsenuf (with the head of a falcon) were destroyed in the storm and poorly restored. The two sides of the coffin are separated by the ankh sign, which stands for life. The style of the coffin is characteristic of the 8th or 9th centuries B.C.


The title of “Songstress of the Sanctuary of Amun” that Sha-Amun-em-su bears marks her out as a member of a special group that existed in Thebes during the 9th to 6th centuries B.C. These women assisted the God’s Wife of Amun during the rituals enacted in the great temple of Amun in Thebes.


The coffin of a singer priestess from Ancient Egypt is feared to have been destroying amid a huge fire that engulfed the National Museum in Rio de Janeiro. Mustafa Waziri, Secretary General of Egypt’s Supreme Council of Antiquities, expressed his deep regret over what happened, calling is “a great loss to humanity and historical heritage.”



Source


2019 April 3 Wisps Surrounding the Horsehead Nebula Image…


2019 April 3


Wisps Surrounding the Horsehead Nebula
Image Credit & Copyright: Mario Zauner


Explanation: The famous Horsehead Nebula in Orion is not alone. A deep exposure shows that the dark familiar shaped indentation, visible just below center, is part of a vast complex of absorbing dust and glowing gas. To bring out details of the Horsehead’s pasture, an amateur astronomer used a backyard telescope in Austria to accumulate and artistically combine 7.5 hours of images in the light of Hydrogen (red), Oxygen (green), and Sulfur (blue). The resulting spectacular picture details an intricate tapestry of gaseous wisps and dust-laden filaments that were created and sculpted over eons by stellar winds and ancient supernovas. The Flame Nebula is visible just to the left of the Horsehead, while the bright star on the upper left is Alnilam, the central star in Orion’s Belt. The Horsehead Nebula lies 1,500 light years distant towards the constellation of Orion.


∞ Source: apod.nasa.gov/apod/ap190403.html


thevintagearab: Bir Hima and The Rub’ al Khali – Richard Wilding

thevintagearab:











Source


teapotify: Standing female figure wearing a strap and a…


teapotify:



Standing female figure wearing a strap and a necklace
Period: Early–Middle Bronze Age
Date: 3rd–2nd millennium B.C.
Geography: Southwestern Arabia
Medium: Sandstone, quartzite
Dimensions: H. 10 5/8 × W. 5 ½ × D. 4 5/16 in. (27 × 13.9 × 10.9 cm)


https://www.metmuseum.org/toah/works-of-art/1998.380/



Source


teapotify: Limestone seated statuette. 


teapotify:



Limestone seated statuette. 



Source


Caption Spotlight (2 April 2019): Dramatic Changes over the…



Caption Spotlight (2 April 2019): Dramatic Changes over the South Polar Cap


The south polar residual cap of carbon dioxide ice rapidly changes. This image was planned as an almost exact match to the illumination and viewing angles of a previous one we took in August 2009 (on the left).


The pits have all expanded and merged, and we can just barely see the patterns in the 2009 image compared to this January 2019 picture. The 2009 image is also brighter and bluer, with more seasonal frost and/or less dust over the surface. These images were both taken in late southern summer, but our 2019 picture is slightly later in the Martian season by about two weeks.


This gap allowed for additional loss of frost that might make the surface darker, but there are also year-to-year changes. In particular, there was a near-global dust storm in the summer of 2018 and late southern spring on Mars, and extra deposits of dust would have warmed the surface and promoted even more disappearance of the frost.


NASA/JPL/University of Arizona


teapotify: Calcite-alabaster miniature stela; carved with the…


teapotify:



Calcite-alabaster miniature stela; carved with the representation of face with a  South Arabian inscription below.
Yemen



Source


teapotify: https://www.britishmuseum.org/join_in/using_digital_i…


teapotify:



https://www.britishmuseum.org/join_in/using_digital_images/using_digital_images.aspx?asset_id=141014001&objectId=365990&partId=1



Source


teapotify: Limestone stela carved with a male face in relief…


teapotify:



Limestone stela carved with a male face in relief and a line of inscription with the name Lahay’Athat
2nd c bc, Yemen



Source


Robotic “Bees” Are About to Join Astronauts in Space

image


There are some things only humans can do in space. The rest can be left to robots. To free up valuable time for astronauts living and working aboard the International Space Station, we’re sending three robotic helpers to the orbiting outpost. Developed and built at our Ames Research Center in California’s Silicon Valley, the cube-shaped Astrobee robots will each stay as busy as a bee flying around the space station and assisting crew with routine tasks like maintenance and tracking inventory. The robots will also help researchers on the ground carry out experiments, test new technologies and study human-robot interaction in space. Learning how robots can best work with humans in close proximity will be key for exploring the Moon and other destinations. Get to know more about our new robots headed to space: 


The Astrobee robots were tested inside a special lab at our Ames Research Center where researchers created a mockup of the space station’s interior. 


image

The flying robots are propelled by fans. They can move in any direction and turn on any axis in space. 


image


Each robot is equipped with cameras and sensors for navigating inside the space station and avoiding obstacles.


image


Claw power! Astrobees have a robotic arm that can be attached for handling cargo or running experiments.




Astrobee is battery powered. When its battery runs low, the robot will autonomously navigate and dock to a power station to recharge.


image

The robots can operate in either fully automated mode or under remote control by astronauts or researchers on Earth.


image


Astrobee builds on the success of SPHERES, our first-generation robotic assistant that arrived at the space station in 2006.  


image

Two of the three Astrobee robots are scheduled to launch to space this month from our Wallops Flight Facility in Virginia! Tune in to the launch at www.nasa.gov/live.


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


First satellite in European SpaceDataHighway forges 20,000 successful laser links


ESA – EDRS Mission logo.


2 April 2019


The European Data Relay System (EDRS)—dubbed the “SpaceDataHighway” by its private operator, Airbus—has passed another milestone.


EDRS-A, the first satellite in what will eventually be a global constellation, has made its 20,000th successful optical link to its customer satellites since its launch in January 2016, marking a world first in laser communication in space.



The European Data Relay System uses lasers to rapidly collect data from Earth-scanning satellites

This milestone provides further evidence that ESA’s Partnership Projects initiative successfully develop sustainable end-to-end systems, right up to in-orbit validation.


The system is a public-private partnership between ESA and Airbus, with significant investment by the German Space Administration DLR.


Satellites that are used to monitor the Earth operate from low-Earth orbits and usually relay the information they have acquired only when they are in a direct line-of-sight with a ground antenna.


EDRS-A rides much higher in the sky, where it can maintain a continuous connection with its ground stations and an almost permanent one with the low-Earth orbiting satellites. The system uses secure laser communication to receive data from the low-Earth orbiting satellites and beams the information back to Earth via radio frequency.


“Earth observation satellites have orbits that mean having to wait up to 100 minutes to transmit information to the ground. That can be a problem when you need information immediately, for example, when trying to provide aid during flooding or wild fires, or help ships navigating through ice sheets,” says Michael Witting, EDRS project manager at the European Space Agency.



Artist’s impression of EDRS-A

“EDRS provides data to the ground rapidly because of its bird’s eye view from its geostationary orbit. Its point-to-point transmission using cutting-edge laser communication technology means data can be transmitted at very high speeds, and it is hard to jam the signal or to eavesdrop on it. EDRS is another example of how ESA’s Partnership Projects federate industry around large-scale programmes, achieving a competitive leap forward and economic impact.”


At present the system is used to collect information from the European Union’s Copernicus programme of Earth observation satellites. EDRS is due to start transmitting data from the Columbus module of the International Space Station later this year, and the system is also open to other commercial customers.


Related links:


European space laboratory Columbus: http://www.esa.int/Our_Activities/Human_and_Robotic_Exploration/Columbus


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


EDRS: http://www.esa.int/Our_Activities/Telecommunications_Integrated_Applications/EDRS


Images, Text, Credit: ESA.


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