пятница, 5 апреля 2019 г.

Tiger geckos in Vietnam could be the next species sold into extinction

While proper information about the conservation status of tiger gecko species is largely missing, these Asian lizards are already particularly vulnerable to extinction, as most of them have extremely restricted distribution. Furthermore, they have been facing severe declines over the last two decades, mostly due to overcollection for the international exotic pet market. Such is the case of the Cat Ba Tiger Gecko, whose tiny populations can only be found on Cat Ba Island and a few islands in the Ha Long Bay (Vietnam).











Tiger geckos in Vietnam could be the next species sold into extinction
Cat Ba tiger gecko (Goniurosaurus catbaensis) in its natural habitat
[Credit: Mona van Schingen]

In their study, a Vietnamese-German research team, led by PhD candidate Hai Ngoc Ngo of the Vietnam National Museum of Nature in Hanoi, provide an overview of the evidence for domestic and international trade in tiger gecko species and update the information about the abundance and threats impacting the subpopulations of the Vietnamese Cat Ba Tiger Gecko in Ha Long Bay. By presenting both direct and online observations, interviews and existing knowledge, the scientists point out that strict conservation measures and regulations are urgently needed for the protection and monitoring of all tiger geckos. The research article is published in the open-access journal Nature Conservation.
Tiger geckos are a genus (Goniurosaurus) of 19 species native to Vietnam, China and Japan. Many of them can only be found within a single locality, mountain range or archipelago. They live in small, disjunct populations, where the population from Ha Long Bay is estimated at about 120 individuals. Due to demands in the international pet trade in the last two decades, as well as habitat destruction, some species are already considered extinct at the localities where they had originally been discovered.


However, it was not until very recently that some species of these geckos received attention from the regulatory institutions in their home countries, leading to the prohibition of their collection without a permit. Only eight tiger geckos have so far had their species conservation status assessed for the IUCN Red List. Not surprisingly, all of them were classified as either Vulnerable, Endangered or Critically Endangered. Nevertheless, none is currently listed by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which could be the only efficient and reliable method to monitor, regulate and police the trade of the species on a global scale.











Tiger geckos in Vietnam could be the next species sold into extinction
Signboard handed over to the Ha Long Bay Management Department to point to the threats and conservation
need of the Cat Ba tiger gecko in English and Vietnamese languages [Credit: Hai Ngoc Ngo]

“Tiger geckos are neither sufficiently protected by law nor part of conservation programmes, due to the lack of substantial knowledge on the species conservation status and probably due to the general lack of public as well as political interest in biodiversity conservation,” they explain. “To date, exact impacts of trade on the species cannot be identified, as data of legal trade are only recorded for species listed in the CITES Appendices.”
During their survey, the researchers tracked local traders in possession of wild-caught tiger geckos representing all five Vietnamese species en route to foreign exotic pet markets, mainly in the United States, the European Union and Japan. The species were also frequently found to be sold in local pet shops in Vietnam, as well as being offered via various online platforms and social media networks like Facebook.


Having spoken to local dealers in Vietnam, the team found the animals were traded via long and complex chains, beginning from local villagers living within the species’ distribution range, who catch the geckos and sell them to dealers for as little as US$4 — 5 per individual. Then, a lizard either ends up at a local shop with a US$7 — 25 price tag or is either transported by boat or by train to Thailand or Indonesia, from where it is flown to the major overseas markets and sold for anywhere between US$100 and 2,000, depending on its rarity. However, many of these delicate wild animals do not arrive alive at their final destination, as their travels include lengthy trips in overfilled boxes under poor conditions with no food and water.


Cat Ba tiger gecko (Goniurosaurus catbaensis) in its natural habitat
[Credit: Mona van Schingen]


Indeed, although the researchers reported a large quantity of tiger geckos labelled as captive-bred in Europe, it turns out that their availability is far from enough to meet the current demands.


In conclusion, the team provides a list of several recommendations intended to improve the conservation of the Asian geckos: (1) inclusion of all tiger geckos in the Appendices of CITES; (2) assessment of each species for the IUCN Red List; (3) concealment of any currently unknown localities; and (4) improvement/establishment of coordinated ex-situ breeding programmes for all species.


Source: Pensoft Publishers [April 01, 2019]



TANN



Archive


Peru: Caral served as cradle of civilization in areas beyond Supe Valley

The impact of the Caral culture went beyond the limits of Supe Valley. The latest discoveries in Aspero — Caral civilization’s fishing town — reveal that trade developed along the coasts of Ecuador and the Amazon area.











Peru: Caral served as cradle of civilization in areas beyond Supe Valley
The archaeological site of Caral covers 626 hectares and is about 5,000 years old
[Credit: Caral Archaeological Zone]

Doctor Ruth Shady Solis — the person in charge of the archaeological works — explained the discoveries suggest new theories concerning the role of Caral inhabitants.
The expert — a competent authority when it comes to the Preceramic period — indicated that some products could be considered part of the trade exchange between regions.


However, others might give a clue of a strong migration from the Amazon to the Coast, due to climate problems.



According to Shady, some of the objects found in Aspero belong to other areas. The same occurs in Miraya or Vichama, where archaeologists found sodalite — a mineral extracted from deposits in Bolivia.
In fact, excavators in Caral found a child buried in the style of the Chinchorro culture — developed between Moquegua and the north of what is now Chile.


Neither walls nor weapons have been found in the area, which suggests this society did not practice war.



Shady underscores that civilization spread from Supe Valley, thus influencing other regions in the continent.


Source: Andina [April 01, 2019]



TANN



Archive


Loss of habitat causes double damage to species richness

Loss and fragmentation of habitat are among the main reasons why biodiversity is decreasing in many places worldwide. Now, a research team with participation of the German Centre for Integrative Biodiversity Research (iDiv) and Martin Luther University Halle-Wittenberg (MLU) has established that the destruction of habitat causes double damage to biodiversity; if habitat patches disappear, not only do the species living there become extinct, but species richness in neighbouring patches also declines. The reason for this additional species loss is the large physical distances between the remaining habitat patches, the researchers write in the journal Ecology Letters.











Loss of habitat causes double damage to species richness
The soda pans in the Seewinkel region (Austria) are extraordinarily precious habitats
[Credit: Zsófia Horváth]

For their study, scientists from the iDiv research centre, the Uni Halle and the WasserCluster Lunz research centre in Austria used long-term data on the presence of invertebrate zooplankton such as little crustaceans and rotifers in the saline ponds (“Salzlacken”) of the Seewinkel region of eastern Austria.


These so-called soda pans are shallow ponds fed by precipitation and groundwater, which are usually less than a square kilometre in size, regularly dry out and can reach a very high salinity. In the 1950s, the 270 square kilometre area of study had more than 110 of these soda pans. Because of agricultural intensification, their numbers had dwindled to about 30 in 2010 – a decline of 70 percent within six decades. In 1957, ecologists found 64 species and in 2010 just 47 – a net loss of 17 species.


What were the reasons why so many plankton species disappeared from the soda pans? Was it just because their habitat was lost or were there other factors? In fact, the researchers found that, based on calculations and models, the decline in the number of soda pans from 110 to 30 should have resulted in the extinction of just four zooplankton species.


“Even if we had not taken into account the number of soda pans, but rather their area, we would have expected a decline of only nine species,” says Prof Jonathan Chase, head of the Biodiversity Synthesis Research Group at iDiv and Uni Halle and senior author of the study. Instead, 17 species went extinct from the region.











Loss of habitat causes double damage to species richness
These little crustaceans belong to the zooplankton analysed in the study. The picture shows a fairy shrimp
(Branchinecta orientalis, 3 – 4cm in size) as well as several water fleas (Daphnia magna, up to 0.5cm)
[Credit: Imre Potyó]

The researchers were, however, able to rule out that deterioration in the quality of the habitat played a role in the additional drop in the number of species; for example, changes in salinity and fluctuations in the nutrient content, water levels and turbidity of the ponds.


“So there must be another factor on landscape scale which is responsible for the extinction of these species in this region,” says first author Dr Zsófia Horváth. Horváth carried out the study at the WasserCluster Lunz research centre in Austria as well as at the iDiv research centre and Halle University.


Spatial processes can explain the sharp decline in species richness; when many soda pans disappear, the distances between those which remain are quite large, greatly reducing the ability of zooplankton to colonise new habitat patches – for example via the passive dispersal of eggs through wind, or as ‘hitchhikers’ on amphibians and birds.


“That species disappear locally happens again and again. But if they have no possibility to repopulate habitat patches, it becomes a problem,” says Jonathan Chase. If there are fewer soda pans in which a specific species dwells, and if the remaining soda pans are far from each other, the possibility for this species to redisperse is low, the scientist explains. This means that local extinction can no longer be countered by recolonization from the region.











Loss of habitat causes double damage to species richness
The scientists have also analysed species richness of rotifers, other members of the zooplankton.
The picture shows the species Brachionus quadridentatus under the microscope
[Credit: Frank Fox, WikiCommons]

Metacommunities, that is, communities of organisms that are distributed over multiple habitat patches and are potentially connected through moving individuals, hence experience an additional effect at the regional level when habitat patches disappear locally. This has always been widely suspected, but has, up to now, rarely been proven because long-term studies are scarce.


Thanks to the data on soda pans in the Seewinkel region, this gap in knowledge has now been closed. “This is important because this effect can now be taken more into consideration in future modelling – for example, when calculating expected losses of biodiversity when habitat is lost,” summarises Chase.


Source: German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig [April 02, 2019]



TANN



Archive


Hybrid species could hold secret to protect Darwin’s finches against invasive...

A hybrid bird species on the Galapagos Islands could help scientists find a way to stop an invasive fly which is killing off the hatchlings of famous Darwin’s finches at an alarming rate, according to new research.











Hybrid species could hold secret to protect Darwin's finches against invasive parasite
Male hybrid tree finch, Galapagos Islands [Credit: Dr. Katharina J. Peters]

10 related species of the iconic Darwin’s finches are being threatened by the invasive fly Philornis downsi from South America, which lays its eggs into birds’ nests where the predators then hatch and devour defenceless chicks before the parents can react.


Newly hatched maggots take up real estate in a chick’s nostril, ear or anywhere they can find blood, and attack at night with more than half of the finches nestlings dying as a result in recent years.


But in a paper published in the scientific journal Royal Society Open Science, lead author and Flinders University Postdoctoral Fellow, Dr Katharina Peters, says hybrid offspring of two famous species, small and medium tree finches, might be more effective at eliminating the parasite in their nests, or their nests are just not as attractive to the adult flies.


“We found finch hybrids have fewer introduced parasites in their nest when compared to their more famous ancestors, with hybrid nests housing only half the number of deadly flies, potentially revealing an effective defence mechanism to combat what is an invasive parasite,” says Dr Peters.


“The hybrids are offspring of small and medium tree finches which aren’t anywhere near as effective at defending against the parasitic fly so the hybrids could potentially have an evolutionary advantage.”











Hybrid species could hold secret to protect Darwin's finches against invasive parasite
Adult Philornis downsi fly (left) and larvae (right) [Credit: Katharina J. Peters,
Jody O’Connor, 2019]

Finch chicks that do somehow survive the attacks are often left with a reminder of their gruesome battle for life- with a permanent hole in their beak.


Senior author and head of Flinders Bird Lab, Professor Sonia Kleindorfer, says survey data has previously indicated finch species with the higest rate of deadly parasite in their nests, are suffering from a dramatic decline in overall numbers.


“Flies have infected the nests of every land bird species on the four inhabited Galápagos Islands and that includes the famous Darwin’s finches, which are part of a heritage system that shaped human thought about how life evolved on planet Earth,” says Professor Kleindorfer.


“If nothing is done, it’s likely that bird populations will become extinct on different islands in the next decades.”


Healthy hybrid Darwin’s finch foraging and extracting P. downsi parasite from a finch nest 


[Credit: Professor Sonia Kleindorfer]


In 2012, experts from around the world established the Philornis Working Group to coordinate their efforts to solve the maggot problem, which includes experts from Flinders University’s Bird Lab.


Members of the group hail from 15 institutions, and gather in the Galapagos to discuss progress, new findings and a way to save these birds and preserve the islands’ ecosystem.


Dr Peters say the next step is to confirm why the hybrid species are so much more effective at eliminating the parasite.


“At this stage we don’t know what the mechanism is behind the reduced fly numbers in hybrid nests.”


“We speculate it’s one of a few options such as novel immune defences, nesting density or the materials used to build the nest itself, as well as anti-parasite behaviour such as picking the larvae off the nestlings by the parents, but more research is needed to actually shed light on this.”


Source: Flinders University [April 02, 2019]



TANN



Archive


Fifth Dynasty tomb and name of new queen discovered at Saqqara

An Egyptian archaeological mission has discovered the tomb of a Fifth Dynasty dignitary named Khuwy during an excavation and documentation survey carried out in south Saqqara, and has also discovered the name of the queen to whom a pyramid complex in the area belonged.











Fifth Dynasty tomb and name of new queen discovered at Saqqara
Credit: Egypt. Ministry of Antiquities

The tomb consists of a superstructure with an L-shaped offering chamber, which was once decorated with reliefs. Only the bottom part of this decoration is preserved, as the white limestone blocks of the other parts were re-used in the construction of other buildings in antiquity.


Mostafa Waziri, secretary-general of the Supreme Council of Antiquities, explained that the mission has found at the north wall of the tomb, the entrance to a unique substructure, which is for the first time clearly inspired by the design of the substructures of the royal pyramids of the Fifth Dynasty.


That part of the tomb starts with a descending corridor, which leads to a vestibule. An entrance in its southern wall gives access to a decorated antechamber. Its decoration represents the tomb owner sitting in front of the offering table on the south and north walls. Moreover, an offering list was depicted on the east wall and the palace-façade on the west wall.


Mohamed Megahed, head of the archaeological mission, told Ahram Online that the mission located the undecorated burial chamber through two entrances in the west wall of the antechamber of the tomb.











Fifth Dynasty tomb and name of new queen discovered at Saqqara
Credit: Egypt. Ministry of Antiquities

“It seems that the space of the burial chamber was almost completely filled with a limestone sarcophagus, which was found entirely destroyed by ancient tomb robbers,” Megahed added.


However, the mission discovered the human remains of Khuwy, which show clear traces of mummification.


An entrance in the south wall of the decorated antechamber leads to a small room, most likely used as a storeroom. The mission found this room filled with debris, with no finds of any value.


“The discovery of this tomb stresses the importance of Djedkare’s era, and the end of the Fifth Dynasty in general,” asserted Megahed.











Fifth Dynasty tomb and name of new queen discovered at Saqqara
Credit: Egypt. Ministry of Antiquities

The mission, in cooperation with an international team of Egyptologists, has also discovered an ancient Egyptian queen who lived during the late Fifth Dynasty in the same pyramid complex.


The mission found the name of queen Setibhor, who was not known before from ancient sources, engraved on a column in the south part of the until-now anonymous pyramid complex.


The complex is located by the pyramid of king Djedkare in south Saqqara, and the identity of its owner was a puzzle that Egyptologists have been trying to solve for decades.


The name and titles of the owner of this unique monument was found on the column made of red granite in the newly uncovered portico of the queen’s complex. The inscription was carved in sunken relief in a rectangle on the shaft of the column, and it reads: “The one who sees Horus and Seth, the great one of the hetes sceptre, the great of praise, king’s wife, his beloved Setibhor.”











Fifth Dynasty tomb and name of new queen discovered at Saqqara
Credit: Egypt. Ministry of Antiquities

The column and the limestone blocks and fragments bearing relief decoration from the temple of the queen were found during exploration and documentation work in the pyramid complex of king Djedkare.


The pyramid complex of queen Setibhor represents one of the earliest pyramids in south Saqqara, built at the end of the Fifth Dynasty, and it is the largest pyramid complex built for a queen during the Old Kingdom.


Moreover, her funerary temple incorporated architectural elements and chambers that were otherwise reserved for the kings of the Old Kingdom only.


The large size of the pyramid complex of queen Setibhor and her title of queen may indicate her direct intervention in helping her husband, king Djedkare, ascend the throne of Egypt at the end of the Fifth Dynasty. It seems that Djedkare wanted to honour his wife by constructing her a huge pyramid complex, with many unusual features, including palmiform granite columns, which constitute an architectural element so far known only in the pyramid complexes of kings and not used in the temples of the queens during the Old Kingdom period.











Fifth Dynasty tomb and name of new queen discovered at Saqqara
Credit: Egypt. Ministry of Antiquities

Megahed said that the mission has also completed the architectural restoration and consolidation of the substructure of the king’s pyramid, which had not been subjected to any restoration work before.


The work of consolidation, restoration and reconstruction of the inner walls of the pyramid represented a vital task for the mission, he said.


The mission is focused on the pyramid complexes of Djedkare and his Setibhor and their associated cemeteries, hoping to obtain more information on the end of the Fifth Dynasty and the beginning of the Sixth Dynasty.


This period witnessed a radical transformation in ancient Egyptian ideology and religious beliefs, such as the appearance of the Pyramid Texts for the first time inside the pyramid of king Unas, the successor of Djedkare, and also the end of the practice of constructing sun temples, which all the Fifth Dynasty predecessors of Djedkare had done.


Author: Nevine El-Aref | Source: Ahram Online [April 02, 2019]



TANN



Archive


Asteroid Explorer Hayabusa2’s Science – Put into Operation


JAXA – Hayabusa2 Mission patch.


April 5, 2019


The National Research and Development Agency Japan Aerospace Exploration Agency (JAXA) separated the SCI (Small Carry-on Impactor) onboard the asteroid explorer Hayabusa2 for deployment to Ryugu and put the SCI into operation.



Artists impression of the Hayabusa2 probes encounter with Ryugu. Image Credit: JAXA

After the start of the operation, the camera (DCAM3) separated from Hayabusa2 captured an image that shows ejection from Ryugu’s surface, which implies that the SCI had functioned as planned.


Hayabusa2 is operating normally. We will be providing further information once we have confirmed whether a crater has been created on Ryugu.



This image captured by the camera separated from Hayabusa2 (DCAM3) shows ejection from Ryugu’s surface, which was caused by the collision of the SCI against Ryugu.


Image taken at 11:36 a.m., April 5, 2019 (Indicated by the camera, Japan time)
Image credit: JAXA, Kobe University, Chiba Institute of Technology, The University of Occupational and Environmental Health, Kochi University, Aichi Toho University, The University of Aizu, and Tokyo University of Science.


Operational Status of Asteroid Explorer Hayabusa2’s SCI


The National Research and Development Agency Japan Aerospace Exploration Agency (JAXA) has carried out operations to separate the SCI (Small Carry-on Impactor) onboard the asteroid explorer Hayabusa2 for deployment to the asteroid Ryugu.


The SCI separation has been confirmed using Hayabusa2’s Optical Navigation Camera-Wide (ONC-W1), it is our assessment that separation of the SCI went as planned.



An image of separated SCI taken with the Optical Navigation Camera – Wide angle (ONC-W1) on April 5, 2019 at an onboard time of around 10:56 JST. Photographed from approximately 500 meters above Ryugu. Image credits: JAXA, The University of Tokyo, Kochi University, Rikkyo University, Nagoya University, Chiba Institute of Technology, Meiji University, The University of Aizu, AIST.


In order to avoid the impact given by the operation of the small carry-on impactor (SCI), Hayabusa2 was moved to the safety zone on the backside of the asteroid before the SCI began to be operated. Hayabusa2 is operating normally.



Latest Navigation Images from the SCI operation. Image Credit: JAXA

We will be providing further information once we have confirmed whether the SCI is operating and whether a crater has been created on Ryugu.


Related Links:


Hayabusa2 Asteroid Probe (ISAS): http://www.isas.jaxa.jp/en/missions/spacecraft/current/hayabusa2.html


Asteroid Explorer “Hayabusa2”: http://global.jaxa.jp/projects/sas/hayabusa2/index.html


Images (mentioned), Text, Credits: Japan Aerospace Exploration Agency (JAXA)/National Research and Development Agency.


Best regards, Orbiter.chArchive link


Jupiter Spiral


NASA – JUNO Mission logo.


April 5, 2019



A cyclonic storm in Jupiter’s northern hemisphere is captured in this image from NASA’s Juno spacecraft. Many bright white cloud tops can be seen popping up in and around the arms of the rotating storm.


The color-enhanced image was taken at 9:25 a.m. PST (12:25 p.m. EST) on Feb. 12, 2019, as the spacecraft performed its 17th science flyby of Jupiter. At the time, Juno was about 5,000 miles (8,000 kilometers) from the planet’s cloud tops, above approximately 44 degrees north latitude.


Citizen scientists Gerald Eichstädt and Seán Doran created this image using data from the spacecraft’s JunoCam imager.


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


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



JUNO spacecraft orbiting Jupiter

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


Image, Animation, Text, credits: NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstadt/Sean Doran.


Greetings, Orbiter.chArchive link


Lake Superior Agate | #Geology #GeologyPage #Agate #Mineral …


Lake Superior Agate | #Geology #GeologyPage #Agate #Mineral


Photo by Lech Darski


Geology Page

www.geologypage.com

https://www.instagram.com/p/Bv4J_CaF2FI/?utm_source=ig_tumblr_share&igshid=h9e4tgfkk1i3


cma-greek-roman-art: Stater: Nike-Terina (reverse), 0,…


cma-greek-roman-art:



Stater: Nike-Terina (reverse), 0, Cleveland Museum of Art: Greek and Roman Art


Size: Diameter: 2 cm (13/16 in.)
Medium: silver


https://clevelandart.org/art/1916.982.b



Source


cma-greek-roman-art: Jug, 2000, Cleveland Museum of Art: Greek…


cma-greek-roman-art:



Jug, 2000, Cleveland Museum of Art: Greek and Roman Art


Size: Diameter: 4.3 cm (1 11/16 in.); Overall: 10.8 x 6.8 cm (4 ¼ x 2 11/16 in.)
Medium: red ware


https://clevelandart.org/art/1916.1991



Source


met-greekroman-art: Terracotta statuette of Eros on a lion,…


met-greekroman-art:



Terracotta statuette of Eros on a lion, Greek and Roman Art


Rogers Fund, 1912

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


Source


met-greekroman-art: Glass cup in the form of the head of an…


met-greekroman-art:



Glass cup in the form of the head of an African, Greek and Roman Art


Gift of Henry G. Marquand, 1881

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


Source


met-greekroman-art: Bead, control, Greek and Roman ArtPurchase…


met-greekroman-art:



Bead, control, Greek and Roman Art


Purchase by subscription, 1895

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


Source


met-greekroman-art: Glass jug, Greek and Roman ArtThe Cesnola…


met-greekroman-art:



Glass jug, Greek and Roman Art


The Cesnola Collection, Purchased by subscription, 1874–76

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


Source


2019 April 5 Pan-STARRS Across the Sky Image Credit: R. White…


2019 April 5


Pan-STARRS Across the Sky
Image Credit: R. White (STScI) and the PS1 Science Consortium


Explanation: This astronomical sky spanning view is a mosaic from the Pan-STARRS observatory. The images were recorded with its 1.8 meter telescope at the summit of Haleakala on planet Earth’s island of Maui. In fact, Earth’s north celestial pole is centered in this across-the-sky projection. A declination of -30 degrees, the southern horizon limit as seen from the Hawaiian Valley Isle, defines the circular outer edge. Crowded starfields and cosmic dust clouds along the plane of our Milky Way galaxy stretch across the scene with the bright bulge of the galactic center at the bottom. Compiled over four years, the image data represent the second edition of data from Pan-STARRS (Panoramic Survey Telescope & Rapid Response System), currently the planet’s largest digital sky survey. In 2017 Pan-STARRS was used to first recognize the interstellar voyage of ‘Oumuamua, visitor to our Solar System.


∞ Source: apod.nasa.gov/apod/ap190405.html


Downloadable genotypes of present-day and ancient DNA data

They’re freely available via the Harvard Medical School at this LINK. The linked web page includes this message:



We would be grateful if users of this dataset could alert us to any errors they detect and help us to fill in missing data. This could include: (1) errors or missing information for location, latitude, longitude, archaeological context, date, and group label, (2) concerns about Y chromosome or mitochondrial DNA haplogroup determinations, and (3) evidence for other problems in the data or annotations for individuals. Please write to Swapan ‘Shop’ Mallick and David Reich with any suggestions. We would also be grateful if members of the community could suggest additional content that would be helpful to add to this page to make it maximally useful. Finally, please let us know if there is any ancient DNA data we should be including that we have missed.



See also…
New release of ADMIXTOOLS with two additional programs

Source


Arianespace – Soyuz ST-B launches four O3b satellites


ARIANESPACE – Soyuz Flight VS22 Mission poster.


April 4, 2019



Soyuz ST-B launches first phase of SES’ O3b constellation

Arianespace VS22 mission: a Soyuz ST-B launch vehicle launched four more O3b satellites, the first six OneWeb satellites, from the Soyuz Launch Complex (ELS) in Sinnamary, French Guiana, on 4 April 2019, at 17:03 UTC (14:03 local time). The four O3b satellites (2,800 kg, approx. 700 kg. for each satellite) are the 58th, 59th, 60th and 61th satellites to be launched by Arianespace for the global satellite operator SES.


With a successful Soyuz launch that completed the first phase of SES’ O3b constellation, Arianespace today reaffirmed is ability to support the growing global market for such in-orbit satellite systems.



Soyuz ST-B launches four O3b satellites

Lifting off mid-day from the Spaceport in French Guiana, the workhorse launch vehicle delivered the 17th, 18th, 19th and 20th O3b satellites into a circular orbit during a flight lasting 2 hours and 22 minutes until final separation. Total payload lift performance was estimated at 3,198 kg.


After an initial powered phase of Soyuz’ three lower stages, the flight – designated VS22 in Arianespace’s numbering system – included three burns of the Fregat upper stage to place its passengers at their targeted deployment point.


A success for global connectivity


“Today’s launch follows the O3b constellation deployments in 2013, 2014 and 2018, enabling commercial service since September 2014,” said Luce Fabreguettes, Arianespace’s Executive Vice President – Missions, Operations & Purchasing. “We are even prouder that this 5th launch marks the completion of the constellation. Mission accomplished!”



O3b satellites

The O3b fleet of medium-Earth orbit (MEO) satellites – part of SES’s bold vision of connecting people and empowering them with opportunities – is a proven non-geostationary constellation that provides commercial broadband services today, delivering carrier-grade services. Operating at an altitude of approximately 8,000 km., it serves customers in nearly 50 countries.


By increasing the O3b constellation’s size from 16 to 20 satellites, the SES Networks business unit of SES will offer enhanced coverage while providing greater service availability and reliability – responding to increasing demand for bandwidth from governments, as well as the telecom, cloud, maritime and energy markets.


For more information about Arianespace, visit: http://www.arianespace.com/


Images, Video, Text, Credits: Arianespace/SES/SciNews.


Greetings, Orbiter.chArchive link


met-greekroman-art: Terracotta relief, Greek and Roman…


met-greekroman-art:



Terracotta relief, Greek and Roman Art


Fletcher Fund, 1931

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


Source


met-greekroman-art: Gold and cloisonné bracelet, Greek and…


met-greekroman-art:



Gold and cloisonné bracelet, Greek and Roman Art


The Cesnola Collection, Purchased by subscription, 1874–76

Metropolitan Museum of Art, New York, NY
Medium: Gold, cloisonne


http://www.metmuseum.org/art/collection/search/242713



Source


met-greekroman-art: Glass jug, Greek and Roman ArtMuseum…


met-greekroman-art:



Glass jug, Greek and Roman Art


Museum Accession

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


Source


Caption Spotlight (4 April 2019): A Crater on the South Polar…


Caption Spotlight (4 April 2019): A Crater on the South Polar Layered Deposits


This image is part of a campaign to image potential impact craters in the south polar layered deposits (ice cap). This feature looks like a strong candidate for an impact crater because it is very circular are still has a raised rim.  


The sizes and densities of impact craters provide an estimate for the age of the landscape, which in turn provides a minimum age for the icy layers.


NASA/JPL/University of Arizona


Hunstanton Cliffs, Norfolk | #Geology #GeologyPage…


Hunstanton Cliffs, Norfolk | #Geology #GeologyPage #UnitedKingdom


The famous red and white striped cliffs at Hunstanton in Norfolk, United Kingdom.

The coastal cliffs include the type section of the Hunstanton Formation of lower reddish limestone which was laid down during the Lower Cretaceous. This is topped by a white chalk layer from the Upper Cretaceous epoch.


Geology Page

www.geologypage.com

https://www.instagram.com/p/Bv2dZjJl3D9/?utm_source=ig_tumblr_share&igshid=ct2k0c5w0o58


Express Delivery from Russia Brings 3.7 Tons of Station Supplies


ROSCOSMOS – Russian Vehicles patch.


April 4, 2019


Traveling about 254 miles over central China, the unpiloted Russian Progress 72 cargo ship docked at 10:22 a.m. EDT to the Pirs docking compartment on the Russian segment of the complex.



Image above: Russia’s Progress 72 resupply ship approaches the International Space Station’s Pirs docking compartment today. Image Credit: NASA.


In addition to the arrival of Progress today, the crewmembers aboard the space station are scheduled to greet two other cargo resupply missions this month. Northrop Grumman’s Antares rocket with Cygnus cargo spacecraft will launch from Pad 0A of Virginia Space’s Mid-Atlantic Regional Spaceport at NASA’s Wallops Flight Facility on Virginia’s Eastern Shore on April 17, followed the next week by the launch of SpaceX’s Falcon 9 rocket and cargo Dragon spacecraft from Launch Complex 40 on Cape Canaveral Air Force Station in Florida.



Progress MS-11 docking to the ISS

SpaceX’s Falcon 9 rocket and cargo Dragon spacecraft also is scheduled to launch from Launch Complex 40 on Cape Canaveral Air Force Station in Florida.


Related links:


Pirs docking compartment: https://www.nasa.gov/mission_pages/station/structure/elements/pirs-docking-compartment


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


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


Best regards, Orbiter.chArchive link


Curiosity Captured Two Solar Eclipses on Mars


NASA – Mars Science Laboratory (MSL) patch.


April 4, 2019


When NASA’s Curiosity Mars rover landed in 2012, it brought along eclipse glasses. The solar filters on its Mast Camera (Mastcam) allow it to stare directly at the Sun. Over the past few weeks, Curiosity has been putting them to good use by sending back some spectacular imagery of solar eclipses caused by Phobos and Deimos, Mars’ two moons.



Animation above: This series of images shows the Martian moon Phobos as it crossed in front of the Sun, as seen by NASA’s Curiosity Mars rover on Tuesday, March 26, 2019 (Sol 2359). Animation Credits: NASA/JPL-Caltech/MSSS.


Phobos, which is about 7 miles (11.5 kilometers) across, was imaged on March 26, 2019 (the 2,359th sol, or Martian day, of Curiosity’s mission); Deimos, which is about 1.5 miles (2.3 kilometers) across, was photographed on March 17, 2019 (Sol 2350). Phobos doesn’t completely cover the Sun, so it would be considered an annular eclipse. Because Deimos is so small compared to the disk of the Sun, scientists would say it’s transiting the Sun.


In addition to capturing each moon crossing in front of the Sun, one of Curiosity’s Navigation Cameras (Navcams) observed the shadow of Phobos on March 25, 2019 (Sol 2358). As the moon’s shadow passed over the rover during sunset, it momentarily darkened the light.



Animation above: This series of images shows the Martian moon Deimos as it crossed in front of the Sun, as seen by NASA’s Curiosity Mars rover on Sunday, March 17, 2019 (the 2,350th Martian day, or sol, of the mission). Animation Credits: NASA/JPL-Caltech/MSSS.


Solar eclipses have been seen many times by Curiosity and other rovers in the past. Besides being cool — who doesn’t love an eclipse? — these events also serve a scientific purpose, helping researchers fine-tune their understanding of each moon’s orbit around Mars.


Before the Spirit and Opportunity rovers landed in 2004, there was much higher uncertainty in the orbit of each moon, said Mark Lemmon of Texas A&M University, College Station, a co-investigator with Curiosity’s Mastcam. The first time one of the rovers tried to image Deimos eclipsing the Sun, they found the moon was 25 miles (40 kilometers) away from where they expected.


“More observations over time help pin down the details of each orbit,” Lemmon said. “Those orbits change all the time in response to the gravitational pull of Mars, Jupiter or even each Martian moon pulling on the other.”



Animation above: This series of images shows the shadow of Phobos as it sweeps over NASA’s Curiosity Mars rover and darkens the sunlight on Monday, March 25, 2019 (Sol 2358). Animation Credits: NASA/JPL-Caltech.


These events also help make Mars relatable, Lemmon said: “Eclipses, sunrises and sunsets and weather phenomena all make Mars real to people, as a world both like and unlike what they see outside, not just a subject in a book.”


To date, there have been eight observations of Deimos eclipsing the Sun from either Spirit, Opportunity or Curiosity; there have been about 40 observations of Phobos. There’s still a margin of uncertainty in the orbits of both Martian moons, but that shrinks with every eclipse that’s viewed from the Red Planet’s surface.


About Curiosity


NASA’s Jet Propulsion Laboratory, a division of Caltech, manages the Mars Science Laboratory Project for NASA’s Science Mission Directorate, Washington. JPL designed and built the project’s Curiosity rover.


Malin Space Science Systems, San Diego, built and operates the Mastcam instrument and two other instruments on Curiosity.


More information about Curiosity is at: http://mars.jpl.nasa.gov/msl/


More information about Mars is at: https://mars.nasa.gov


Animations (mentioned), Text, Credits: NASA/Tony Greicius/JPL/Andrew Good.


Greetings, Orbiter.chArchive link


Record-Breaking Satellite Advances NASA’s Exploration of High-Altitude GPS


NASA – Magnetospheric Multiscale (MMS) patch.


April 4, 2019


The four Magnetospheric Multiscale (MMS) spacecraft recently broke the world record for navigating with GPS signals farther from Earth than ever before. MMS’ success indicates that NASA spacecraft may soon be able to navigate via GPS as far away as the Moon, which will prove important to the Gateway, a planned space station in lunar orbit.



Image above: Illustration of the four MMS spacecraft in orbit in Earth’s magnetic field. Image Credit: NASA.


After navigation maneuvers conducted this February, MMS now reaches over 116,300 miles from Earth at the highest point of its orbit, or about halfway to the Moon. At this altitude, MMS continued to receive strong enough GPS signals to determine its position, shattering previous records it set first in October 2016 and again in February 2017. This demonstrates that GPS signals extend farther than expected and that future missions can reliably use GPS at extreme altitudes.


“At the first apogee after the maneuvers, MMS1 had 12 GPS fixes, each requiring signals from four GPS satellites,” said Trevor Williams, the MMS flight dynamics lead at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “When we began the mission, we had no idea high-altitude GPS would be such a robust capability.”



NASA’s MMS Captures Magnetic Reconnection in Action

Video above: On Oct. 16, 2015, MMS traveled straight through a magnetic reconnection event at the boundary where Earth’s magnetic field bumps up against the sun’s magnetic field. Video Credits: NASA’s Goddard Space Flight Center/Duberstein.


MMS’ orbit shift allows it to continue its mission to better understand the complex magnetic processes around Earth. MMS studies a fundamental process that occurs throughout the universe, called magnetic reconnection, in which magnetic fields collide and explosively release particles in all directions. Near Earth, reconnection is a key driver of space weather, the dynamic system of energy, particles and magnetic fields around Earth which can adversely impact communications networks, electrical grids and GPS navigation. Magnetic reconnection was long predicted by physicists, but not directly observed until the MMS mission.


To study Earth’s magnetosphere, the region of space dominated by the planet’s magnetic field, MMS spacecraft maintain a highly elliptical orbit around Earth. A highly elliptical orbit resembles a long oval around the globe with an extreme high point, or apogee, and low point, or perigee.


MMS’ tight formation and highly elliptical orbit require extremely accurate navigation data from GPS satellites, which are operated by the U.S. Air Force. The main GPS antenna signals enable navigation down on Earth, but precise high-altitude navigation requires both these as well as signals from the antenna’s side lobes. Side lobe signals radiate out to the side of the direction an antenna is pointing and extend past Earth.



Image above: A simplified antenna radiation pattern with different lobes of radiation extending from the antenna. Image Credit: NASA.


Communications engineers usually consider these side lobes wasted energy. However, the signals can be used by satellites at high altitudes on the opposite side of the globe as the GPS satellite. (Such high-altitude missions fly above GPS satellites’ orbit.) Previously, most engineers considered the upper limits of the GPS navigation in space to be an altitude of about 22,000 miles, or the altitude of satellites in geosynchronous orbit — until MMS.


Additionally, the navigation maneuvers allowed the spacecraft to gather data not available to scientists during normal operations.



MMS Spacecraft Transition to Tetrahedral Flying Formation

Video above: Visualization of MMS’ transition to its tight, tetrahedral formation in July, 2015. Video Credits: NASA’s Goddard Space Flight Center.


“MMS usually flies in a close, tetrahedral formation [that looks like a pyramid],” said Thomas Moore, the project scientist for MMS at Goddard. “During the orbit-raising maneuvers, the spacecraft became a [straight line or] ‘string of pearls,’ which gave us unique data about the magnetosphere that may further our understanding of magnetic reconnection.”


MMS’ tight configuration and record-breaking GPS fixes would not be possible without the mission’s Navigator GPS Receiver, an instrument developed at Goddard. It can detect faint GPS signals while withstanding the harsh radiation environment within the magnetosphere. NASA has made this revolutionary technology available for licensing through the Technology Transfer program, ensuring that commercial enterprise can also benefit from this innovation.



Image above: A diagram showing how GPS antenna signals can serve spacecraft at high altitudes. Image Credit: NASA.


NASA is exploring the upper limits of GPS service with more than just MMS. NASA navigation experts have run simulations demonstrating that these services could extend even farther when taking into account the collection of six international GPS-like constellations. These constellations are collectively referred to as global navigation satellite systems (GNSS).


In fact, NASA simulations show GNSS signals could even be used for reliable navigation in lunar orbit, just as a car uses GPS on an interstate highway. Engineers are considering using GNSS signals in the navigation architecture for the Gateway, an outpost in orbit around the Moon that will enable sustained lunar surface exploration.


“We’re working with the international community to document GNSS performance for space users, including side lobe signals,” said Joel Parker, a Goddard navigation engineer representing NASA internationally in GNSS policy. “A better understanding of GNSS capabilities will allow high-altitude missions to take advantage of the robust navigation signals they provide.”


Thanks to MMS and NASA’s navigation engineers, the sky is no longer the limit.


NASA’s Science Mission Directorate provides strategic oversight to MMS. Goddard’s Explorers and Heliophysics Projects Division manages the mission. The four MMS spacecraft launched on March 13, 2015, from NASA’s Kennedy Space Center in Cape Canaveral, Florida, on board an Atlas V launch vehicle.


NASA’s Space Communications and Navigation (SCaN) program office oversees the agency’s work in navigation policy related to GNSS. NASA, consulting the United Nations International Committee on GNSS (ICG), collaborates with other U.S. agencies and the six international GNSS providers to define GNSS requirements and develop additional capabilities. The team of SCaN navigation specialists charged with aiding the ICG are based out of the Exploration and Space Communications projects division at Goddard.


Related links:


Magnetospheric Multiscale (MMS): https://mms.gsfc.nasa.gov/


Navigator GPS Receiver: https://ntts-prod.s3.amazonaws.com/t2p/prod/t2media/tops/pdf/NavigatorSpecSheet_Final1.pdf


Technology Transfer: https://technology.nasa.gov/


Space Communications and Navigation (SCaN): https://www.nasa.gov/directorates/heo/scan/index.html


Goddard Space Flight Center (GSFC): https://www.nasa.gov/centers/goddard/home/index.html


Images (mentioned), Videos (mentioned), Text, Credits: NASA/Rob Garner/Goddard Space Flight Center, by Danny Baird.


Greetings, Orbiter.chArchive link


Featured

    Солнечное затмение 14 декабря 2020 года  — полное  солнечное затмение  142  сароса , которое лучше всего будет видно в юго-восточной час...

Popular