четверг, 18 июля 2019 г.

Exiled moons may explain astronomical mysteries

Moons ejected from orbits around gas giant exoplanets could explain several astronomical mysteries, an international team of astronomers suggests.











Exiled moons may explain astronomical mysteries
Did Jupiter once have ‘ploonets’? [Credit: NASA/Johns Hopkins University Applied Physics Laboratory/
Southwest Research Institute/Goddard Space Flight Center]

Researchers led by Mario Sucerquia, from the Universidad de Antioquia, Colombia, and Jaime Alvarado-Montes from Australia’s Macquarie University, modelled the likely behaviour of giant exomoons predicted to form around massive planets—and discovered that they would be expelled and sent packing.


Roughly 50 percent of these ejected moons would survive both the immediate expulsion and avoid any subsequent collision with the planet or the star, ending up as quasi-planets travelling around the host star, but in eccentric «Pluto-like» orbits.


These rogue moons—dubbed «ploonets» by Sucerquia, Alvarado-Montes and colleagues—could potentially explain several puzzling phenomena, not the least of which is why astronomers have so far confirmed the existence of at least 4098 exoplanets, but not a single exomoon.


Most of the planets discovered thus far are of a type known as Hot Jupiters, a fact that reflects mainly the limits of current detection technology. Previous research indicates that at least some of these should be orbited by large moons.


Their absence, the researchers write in a paper soon to be published in the journal Monthly Notices of the Royal Astronomical Society and currently available on arXiv, could be explained by a scenario in which the angular momentum between the two bodies results in the moon escaping the gravitational pull of its parent.


«These moons would become planetary embryos, or even fully-fledged planets, with highly eccentric orbits of their own,» explains Alvarado-Montes.


While conceding that ploonets remain hypothetical, the researchers say their existence would offer a possible explanation for several challenging results produced by NASA’s now-retired Kepler space telescope.


These include the puzzling dips in the light-curves emanating from a formally known as KIC-8462852.


«It’s better known as Tabby Star,» says Alvarado-Montes, «and the strange changes in its light intensity have been observed for years, but are still not understood. Ploonets could be the answer.»


They might also explain apparent evidence of cannibalism between some stars, or the existence of «exocomets» around others.


Ploonets, thus, may be a vital piece of the planetary puzzle, but, as yet, their existence remains unproven.


Sucerquia, Alvarado-Montes and colleagues concede that even if they do exist, they may deteriorate too rapidly to ever be observed.


«If, on the other hand,» they write, «the timescales are large enough, we could have real chances to detect them in the near and middle future.»


Source: Macquarie University [July 12, 2019]




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5000 tons of plastic released into the environment every year

Overall, around 5,120 tons of the seven types of plastic are discharged into the environment each year. This is around 0.7% of the total amount of the seven plastics consumed in Switzerland each year (amounting to a total of around 710,000 tons). According to Empa’s modelling, around 4,400 tons of macroplastic are deposited on soils every year. In addition, about 100 tons of macroplastic are emitted to waters. 600 tons of microplastics end up in or on soils and about 15 tons in waters. The amount of microplastics is thus much smaller than that of macroplastics; in contrast, the number of microplastic particles that could have an impact on organisms is much larger.











5000 tons of plastic released into the environment every year
Credit: Bernd Nowack/Empa

An Empa study focused on specific types of plastic: polyethylene (LD-PE and HD-PE), polypropylene, polystyrene and expanded polystyrene, PVC and PET used for example in packaging, textiles, insulation materials and agricultural films. The researchers followed the path of these plastics to the Swiss environment from production through use to disposal and developed a model, with which these material flows can be calculated. They distinguish between microplastics (smaller than 5 millimeters) and macroplastics (larger than 5 millimeters).


For an overall picture of plastic pollution in Switzerland, however, tire abrasion should also be taken into account. Several studies have identified this material as the largest source of microplastics. A current study at Empa will provide further information on this source of plastic pollution.


The investigation of the seven types of plastic shows that the amount of plastic that gets into the soil is about 40-times higher than the amount that is discharged into water bodies. The main reason for this is littering—the careless throwing away of waste –, which pollutes in particular soils, but also waters, with macroplastics.


The cleaning of public spaces allows the collection of a large part of this plastic. Nevertheless, part of it remains lying around. Another significant source of macroplastic in soils is the use of plastic films in agriculture. Macroplastic also reaches the soils through the composting of organic waste that contains plastic.











5000 tons of plastic released into the environment every year
Credit: Bernd Nowack/Empa

The most important sources of microplastics in soils are agriculture and the construction industry, for example through the wear and tear of foils and pipes and the installation and dismantling of insulation on houses. To a lesser extent, waste disposal also contributes to microplastic pollution by shredding plastic waste for recycling.


The main sources of microplastics in waters are the washing and wearing of synthetic fiber clothing as well as cosmetics. Measured against the modelled soil contamination, however, these sources appear low. In addition, efficient wastewater treatment plants filter a large part of microplastic out of the wastewater. A recent Empa study has shown that currently microplastics pose no threat to aquatic organisms in Europe.


Empa’s calculations make it possible to identify future areas of research and action. In particular, the plastic contamination of soils should be investigated more thoroughly. Depending on the type of plastic used, there are various options for action: Consumers must be made even more aware of the fact that disposable packaging should be disposed of as waste.


Improved cleaning measures, for example along roads, prevent the pollution of the environment with discarded waste. In agriculture, the input of plastics into the soil must be reduced. In the waste and construction industries, companies should be made aware of the issue of plastic pollution. At the political level, several initiatives are calling for measures to be taken in the field of plastics. The FOEN is currently considering further steps to reduce the environmental impact of plastics.


The findings are published in Environmental Science & Technology.


Author: Michael Hagmann | Source: Swiss Federal Laboratories for Materials Science and Technology [July 12, 2019]



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Conference sheds light on 10 years of excavations at Petra Church, Temple of Winged Lions

Excavations take time, money, planning, cooperation, conservation and publishing, said Director of the American Centre of Oriental Research (ACOR) Barbara Porter at a presentation on the Petra Church and the Temple of the Winged Lions on Monday.











Conference sheds light on 10 years of excavations at Petra Church, Temple of Winged Lions
Temple of the Winged Lions, Petra (ca. AD. 25-363). Photograph taken from the east showing
AFCP supported interventions completed in 2017 [Credit: Yusuf Ahmed/ACOR]

The presentation titled, “Lecture for Tour Guides of Petra: A Story of Two Sites”, was held at the Petra Visitor Centre and hosted by the Petra Development and Tourism Region Authority to shed light on the two sites and their significance.


The Petra Church and the Temple of the Winged Lions are located in the north-eastern part of the ancient city of Petra, in the city’s centre, the director elaborated.


“Why was the Petra Church excavation so different?” Porter asked.


For one, it started without funding in 1991, Porter explained, adding that mosaic fragments depicting the four seasons were found at the Petra Church.











Conference sheds light on 10 years of excavations at Petra Church, Temple of Winged Lions
Aerial view of the Petra Church, excavated by ACOR in the early 1990s,
where the famous Petra Papyri were discovered [Credit: ACOR]

The motifs of four seasons and different animals are represented in the mosaics of the Petra Church, the scholar underlined.


“We have spring, summer, fall and winter, so there is the idea of the cycle of mankind; [and its] relationship with God and cosmos… represented in a form of these images,” Porter said, adding that different artists’ hands were recognisable in these visual representations.


In 1993, the discovery of papyri scrolls found at the church also depicted life in Byzantine Petra between the 4th and 6th centuries, Porter said.


The Temple of the Winged Lions is located just metres away from the Petra Church, ACOR Associate Director Jack Green said, adding that a project to excavate the temple was initiated in 2009 and has lasted for 10 years.











Conference sheds light on 10 years of excavations at Petra Church, Temple of Winged Lions
Petra Church as it is today [Credit: ACOR]

The Temple of the Winged Lions sits at the end of Petra’s “Sacred Quarter”, and commemorates the goddess Al Uzza, along with three other temples devoted to different deities, Green highlighted.


“The temple was built in the early 1st century AD and most likely destroyed in 363AD by an earthquake,“ Green said, adding that “from ancient sources winged lions were associated with protection of female deities”.


However, after the earthquake there are indications that the temple was used as a masonry dump, he claimed.


On Tuesday, the Petra College of Tourism and Archaeology also organised a workshop titled, “The Temple of the Winged Lions”, to raise awareness of the temple among tour guides, students and archaeological experts.











Conference sheds light on 10 years of excavations at Petra Church, Temple of Winged Lions
Seasons Mosaic from Petra [Credit: © Jean Housen/WikiCommons]

“It is very important to be aware and educated about cultural heritage,” said Franco Sciorilli, an Italian mosaicist who has spent 25 years working in the Middle East.


Sciorilli also emphasised geological differences between Petra, Madaba and other areas of Jordan where mosaics are located, and what challenges professionals face in order to conserve them.


Author: Saeb Rawashdeh | Source: The Jordan Times [July 13, 2019]



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Ancient Scythian burial mound excavated in Russia’s Stavropol

Russian archaeologists have confirmed that the Scythians were present in the Ciscaucasia (northern Caucasus) in the last third of the 5th century BC, refuting the testimony of the ancient Greek historian Herodotus, who claimed that by that time they had left these lands. The scientists drew their conclusions by determining the date of the artefacts found in the mound near the village of Novozavodennoe. There are still a few excavated mounds in Stavropol Territory, the study of which may lead to new discoveries. Features of monuments will allow local archaeologists to study in detail the everyday life of Scythians in Russia.











Ancient Scythian burial mound excavated in Russia's Stavropol
Kurgan embankment section [Credit: Faculty of History of Lomonosov
Moscow State University]

In the 7th century BC, the Scythians regularly undertook campaigns in the Transcaucasus and further south — in the Middle East. The ideal springboard for military operations was the Ciscaucasia, where in the 1970s archaeologists found traces of Scythian presence in the form of burial mounds in which important members of the community were buried (Krasnoznamenskie mounds, Novozavodennoe I, Novozavodennoe II, Nartan I, etc.). And although later the Scythians were displaced from the Middle East, they continued to reside in the Ciscaucasia at the end of the 5th and 4th centuries BC. This conclusion was drawn by scientists on the basis of excavations, which since 2015 have been carried out at the burial mound Novozavodennoe III in the Stavropol Territory discovered in the late 1980s.
«Kurgans are located near the village of the same name and represent multilevel structures: mounds, gravestones and gravestones in which noble Scythians were buried,» said Anatoly Kantorovich, Head of the Department of Archaeology of the Faculty of History at Lomonosov Moscow State University.


During the investigation of each of the burial mounds, the scientists found buried structures consisting of a wooden and reed-bush covering of the grave pit, an earthen buttress (located on the perimeter of the burial structure) and a ritual platform around the grave. In the ditches surrounding the mounds, archaeologists found the remains of sacrificed horses, which the Scythians buried with the aristocracy. In addition, the excavations managed to find the remains of stone stelae, which were allegedly destroyed by the partial looting of graves.











Ancient Scythian burial mound excavated in Russia's Stavropol
Clearing the bottom of the grave pit [Credit: Faculty of History of Lomonosov
Moscow State University]

«A study of the mounds of Novozavodennoe III revealed that, unfortunately, they were plundered in antiquity,» added Anatoly Kantorovich. «However, before the robbery, the space inside the grave pits was partially covered with earth that came from the tumulus embankments through the gravestones. Among them is an aryballos lekythos (ancient Greek ceramic vessel for aromatic oils) depicting the flying goddess Nike with a vase in her hands. And also a number of gold ornaments (for example, strips for garments), made in a typical Scythian ‘animal’ style — via which the artists succinctly depicted existing and mythical animals, showing the gracefulness and power of nature.»
Scientists also discovered fragments of armour and bronze horse-heads, which may have served as amulets. In addition to Scythian and Greek objects, artefacts of the Koban and Meotian cultures that existed in the area during the same historical period were found in the burial grounds.


Chronological examination of the findings helped to establish the age of the mounds. In particular, the aryballos lekythos discovered at the site of excavation dates back to the last third of the 5th century BC. Therefore, the tomb could not have been built before this period.











Ancient Scythian burial mound excavated in Russia's Stavropol
Credit: Faculty of History of Lomonosov Moscow State University

«A high degree of accuracy in determining the age of objects is associated with the ability to compare them with specific types of artefacts, each of which corresponds to a particular stage in the development of art,» explained Vladimir Maslov, a researcher at the Scythian-Sarmatian Archaeology Department of the Institute of Archaeology of the Russian Academy of Sciences. «Fortunately, the style changes took place regularly, which makes these periods relatively narrow and the results of the dating reliable.»
According to the writings of Herodotus, which he made in the 5th century BC in his work ‘History’, the Scythians left the Ciscaucasia in an earlier period, probably during the transition from the Scythian ‘Archaic’ period of the 7th — 6th centuries BC to the Scythian ‘Classical’ period of the 5th — 4th centuries BC.


However, as a result of the analysis of the recovered artefacts from the mound group Novozavodennoe III, the researchers managed to establish that the burials were made later than this time, that is, the Scythians stayed in the Ciscaucasia for a longer period than Herodotus had supposed.


The scientific importance of studying the mounds was confirmed by the State Museum of Oriental Studies: «The research of the monument Novozavodennoe III has demonstrated that the Scythians stayed in the Pre-Caucasus until the 4th century BC, whereas earlier it was believed that by that time they had already left for the Dnieper River and partially mixed with the local population», noted Vladimir Ehrlich, the chief research fellow of the Department of the History of Material Culture and Ancient Art of the State Museum of Oriental Art. «And the Scythians remained together with their elite, having preserved the traditional burial rites of chiefs and elite military leaders, who could afford to own expensive Greek pottery and gold jewellery.»


According to the results of the latest research, Novozavodennoe III is a unique site in which there are Scythian burial mounds belonging to two different periods in the Ciscaucasia (the 7th and early 6th century BC and the late 5th and 4th century BC). At the same time, there are still several mounds in the vicinity of the village which have not yet been excavated or attributed to any historical period. According to archaeologists, their research will lead to new discoveries and replenish the collections of museums with Scythian artefacts. However, to achieve the results, archaeologists must work quickly, as some of the mounds are located in agricultural zones and may be destroyed by ploughing with heavy machinery.


Author: Alexander Bulanov | Source: iz.ru [trsl. TANN June 16, 2019]



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Grave of second king of Hungary found

Scientists believe they have found the grave of Peter I Orseolo, second king of Hungary, in the crypt of the Cathedral. Peter and Paul in pécs in the South-West of the country.











Grave of second king of Hungary found
Excavation in the crypt of Pécs Cathedral [Credit: Tamás Sóki, MTI]

No remains in the tomb were found, probably because they were intentionally displaced centuries later, writes the online edition of the Chronicle.info with reference to NV.
A team of archaeologists from the Museum of Janus Pannonia was hoping to determine the location of the first Cathedral. Peter and Paul, built in the 11th century. They found the wall under the vault, which was part of the original design. Near it were found the empty grave. As only the founders of the churches were buried in Hungary from the 11th century so it is obvious that it was just such a burial.


The remains from the graves were carefully exhumed, disturbed by the subsequent construction of a dug ditch. This indicates that the remains belonged to someone famous because they were taken with great care to transfer to a new location. There are only two likely candidates: king Peter or the blessed Maurus, second Bishop of Pécs. The moor, however, died about the year 1075, after the construction of the new Church, therefore, grave almost certainly belongs to Peter.











Grave of second king of Hungary found
Empty Tomb of Peter Orseolo [Credit: Tamás Sóki, MTI]

Peter was the son of Grimaldi, younger sister of the first Hungarian king St. Stephen. Grimaldo married a Venetian Doge Ottone Orseolo, and Peter was born in 1011 in Venice. When in 1026 Ottone Orseolo was overthrown, Peter went to visit their uncle in Hungary, and was the commander of his army. As the only son of Stephen died on a hunting trip, Peter Orseolo inherited the Hungarian throne in 1038.
He ruled in 1038-1041 and 1044-1046 years. Second time overthrew him, a popular uprising of the pagans in Hungary. The Governor was blinded and died in 1046 or year or a decade later. However, it sure was buried in the Cathedral of St. Peter and Paul Church, which he built on the site of late Roman cemetery.


The original Cathedral of St. Peter was burned in the year 1064. The one that stands today was built on its remains.











Grave of second king of Hungary found
Roman burial of the late 4th century [Credit: Tamás Sóki, MTI]

Archaeological excavations have discovered the remains of a Roman cemetery the late 4th century. They allow us to conclude that the Christian practice reached this region of Hungary much earlier than expected.


The diocese plans to make the archaeological monuments permanent part of the Church, not to perezahoroneny them. Thus, the crypt visitors can see an ancient burial.


Source: The Mice Times of Asia [July 16, 2019]



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Roman coin stash ‘may have been linked to Boudiccan revolt’

A hoard of Roman coins found in a field may have been hidden there during the Boudiccan revolt, an expert has said. The trove of 60 denarii, dating between 153BC and AD60-61, was found in a field near Cookley, in Suffolk, by a metal detectorist.











Roman coin stash 'may have been linked to Boudiccan revolt'
The coins dated between 153BC and AD61 [Credit: Suffolk County Council]

Dr Anna Booth, who examined the find, said there «might be a link with the Boudiccan revolt» and the coins. Queen Boudicca led the Iceni tribe against the Romans in AD61 which led to the destruction of Colchester.
Most of the coins dated from the Republic era, pre-27BC, but there were also denarii minted during the reigns of emperors Augustus, Tiberius, Caligula and Nero.


Dr Booth said: «This hoard is interesting because the latest coin dated to the reign of Nero in AD60-61. The final coin is often an indication of when a hoard is likely to have been deposited. There might be a link with the Boudiccan revolt which took place in AD61 in this region.»











Roman coin stash 'may have been linked to Boudiccan revolt'
The coins may have been buried to hide them during the Boudiccan revolt, an expert said
[Credit: Suffolk County Council]

She added: «It was quite a tumultuous time in East Anglia. There does seem to be a slight increase in hoarding in this period. It is a stretch of the imagination, we are not 100% sure, but in this region it is tempting to say this is because of what was happening in this period.»
Thousands died during Boudicca’s revolt across East Anglia after she united local tribes against the Roman rulers. Colchester, then the capital of Roman Britain, London and St Albans were all destroyed before she was defeated.


The find, from August 2018, was made up of 58 solid silver coins, two of which were silver-plated copies. Senior coroner Nigel Parsley declared it to be treasure at an inquest in Ipswich.


Source: BBC News Website [July 16, 2019]



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Third European service module for Orion to ferry astronauts on Moon landing


NASA — Orion Crew Vehicle patch.


18 July 2019


NASA and ESA have a long term plan for Europe to deliver the European Service Modules for Orion. With NASA’s announcement to bring humans back to the lunar surface before the end of 2024, it was also decided that the third ESA-provided European Service Module will contribute to this mission.



Orion and European Service Module orbiting the Moon

The Artemis-3 mission is slated to launch on NASA’s Space Launch System in 2024 and will send up to four astronauts on board Orion to a lunar orbit where the spacecraft will dock at the planned Gateway. From there, two of the astronauts will board a lander to ride down to south pole of the Moon.


ESA has already supplied the first European Service Module that is being connected to Orion’s Crew Module this month. The second module is being built in Bremen, Germany, for shipment next year to USA.


Third mission landing on the Moon


The agreement gives the go-ahead to start building the third European Service Module for Orion, it will provide everything the astronauts need to live and arrive safely in lunar orbit including air, water, electricity, propulsion, temperature control and structural stability.


A contract for two European Service Modules is already in place with ESA’s prime contractor Airbus DS in Bremen, early procurements for the third have been initiated, and the full contract is currently under negotiation.


The Artemis-3 mission will involve the landing on the Moon of two astronauts, the 13th and 14th humans to walk on the Moon. For the first time they will visit the south pole of the Moon, a place with permanently-lit areas and eternal shadows, where they will seek ancient lunar ice.



Orion docked to Gateway

“The team welcomed the agreement with elation,” says ESA’s Philippe Deloo of the European Service Module team. “We are already proud to be developing the first spacecraft to return humans to the Moon, but the spacecraft that will see humans land on the Moon is on another level.”


“Working on this third module really brings it home: we are working on the hardware that NASA aims to bring the first woman to the Moon,” says Nico Dettmann, ESA’s head of development at Human and Robotic Exploration.



“The Orion spacecraft is instrumental to the infrastructure we are building around the Moon – including assembling the Gateway and returning samples gathered by robotic missions,” concludes Nico. “We are pleased to continue the fruitful international exploration cooperation with NASA, 50 years after the first Apollo landings.”


ESA is joining the international space community in celebrating the 50th anniversary of humankind first setting foot on the Moon and paying tribute to the men and women who took part in this endeavour, some of whom went on to work in later NASA, ESA and international space programmes. Today, ESA and our partners are busy preparing to return humans to the surface of the Moon. During this week, we will focus on the different lunar missions being prepared by ESA and highlight of some fascinating European contributions to lunar exploration.


Related links:


Orion: http://www.esa.int/Our_Activities/Human_and_Robotic_Exploration/Orion


NASA Orion: https://www.nasa.gov/exploration/systems/orion/index.html


Automated Transfer Vehicle (ATV):
http://www.esa.int/Our_Activities/Human_and_Robotic_Exploration/ATV


Images, Text, Credits: ESA/K.Oldenburg/NASA/ATG Medialab.


Best regards, Orbiter.chArchive link


Angelic halo orbit chosen for humankind’s first lunar outpost


Lunar Gateway (project patch).


18 July 2019


Mission planners at NASA and ESA’s Operations Centre (ESOC) have spent months debating the pros and cons of different orbits, and have now decided on the path of the lunar Gateway.



Orbiting lunar Gateway

Like the International Space Station, the Gateway will be a permanent and changeable human outpost. Instead of circling our planet however, it will orbit the Moon, acting as a base for astronauts and robots exploring the lunar surface.


Like a mountain refuge, it will also provide shelter and a place to stock up on supplies for astronauts en route to more distant destinations, as well as providing a place to relay communications and a laboratory for scientific research.



Gateway with Orion over Moon

Mission analysis teams at ESOC are continuing to work closely with international partners to understand how this choice of orbit affects vital aspects of the mission – including landing, rendezvous with future spacecraft and contingency scenarios needed to keep people and infrastructure safe.


The angelic halo orbit


The Gateway, it has recently been decided, will follow a ‘near-rectilinear halo orbit’, or NRHO.



Angelic halo orbit for Gateway

Instead of orbiting around the Moon in a low lunar orbit like Apollo, the Gateway will follow a highly ‘eccentric’ path. At is closest, it will pass 3000 km from the lunar surface and at its furthest, 70 000 km. The orbit will actually rotate together with the moon, and as seen from the Earth will appear a little like a lunar halo.


Orbits like this are possible because of the interplay between the Earth and Moon’s gravitational forces. As the two large bodies dance through space, a smaller object can be ‘caught’ in a variety of stable or near-stable positions in relation to the orbiting masses, also known as libration or Lagrange points.



The Moon as seen from the Space Station

Such locations are perfect for planning long-term missions, and to some extent dictate the design of the spacecraft, what it can carry to and from orbit, and how much energy it needs to get – and stay – there.


Travelling on the NRHO path, one revolution of the Gateway in its orbit about the Moon would take approximately seven days. This period was chosen to limit the number of eclipses, when the gateway would be shrouded by the Earth or Moon’s shadow.


“Finding a lunar orbit for the gateway is no trivial thing.” says Markus Landgraf, Architecture Analyst working with ESA’s Human and Robotic Exploration activities.



Gateway, Heracles and Orion

“If you want to stay there for several years, the near rectilinear halo orbit is slightly unstable and objects in this orbit do have a tendency of drifting away”.


To keep the Gateway in position, regular small station-keeping manoeuvres will be required.


Take the stage


So why this orbit? The fundamental limiting factor when moving parts from Earth, to a potential lunar base and the Moon’s surface, is energy.


“In human spaceflight we don’t fly one single, monolithic spacecraft,” explains Florian Renk, Mission Analyst in ESOC’s Flight Dynamics Division.


“Instead we fly bits and pieces, putting parts together in space and soon on the surface of the Moon. Some parts we leave behind, some we bring back – the structures are forever evolving.”



The Gateway concept

To escape Earth’s gravitational pull requires a huge amount of energy. To then land on the Moon and not hurtle straight past it, we have to slow down by losing that same energy. We can save some of this energy by leaving parts of the spacecraft in orbit, taking only what we need to the surface of the Moon.


A permanent base in this orbit around the Moon will act as a staging post, from where parts can be left behind, picked up and assembled. After liftoff, only a moderate manoeuvre will be needed to slow a visiting spacecraft to rendezvous with the Gateway.


The Lunar lander will then transport people, robots and infrastructure down to the surface when the Gateway is closest to the Moon, which happens about every seven days. Likewise, a transfer window to the gateway opens about every seven days for the return trip from the lunar surface.


Forward to the Moon


During the 2020s, the Gateway will be assembled and operated in the vicinity of the Moon, where it will move between different orbits and enable the most distant human space missions ever attempted.


It will offer a platform for scientific discovery in deep space and build invaluable experience for the challenges of future human missions to Mars.



View from space gateway

“The flight dynamics expertise here at ESOC is unique in Europe,” adds Rolf Densing, ESA’s Director of Operations.


“Our analysts and flight dynamics experts provide support to a full range of missions, including some of the most complex and exciting like the lunar Gateway. We can’t wait to see this ambitious international endeavour realised.”


Related articles:


Third European service module for Orion to ferry astronauts on Moon landing
https://orbiterchspacenews.blogspot.com/2019/07/third-european-service-module-for-orion.html


Gateway to the Moon
https://orbiterchspacenews.blogspot.com/2019/03/gateway-to-moon.html


NASA’s Lunar Outpost will Extend Human Presence in Deep Space
https://orbiterchspacenews.blogspot.com/2018/02/nasas-lunar-outpost-will-extend-human.html


Related links:


European vision for space exploration: http://www.esa.int/Our_Activities/Human_and_Robotic_Exploration/A_new_European_vision_for_space_exploration


Lunar exploration interactive guide: http://lunarexploration.esa.int/#/intro


ESOC: http://www.esa.int/About_Us/ESOC


Flight Dynamics: http://www.esa.int/Our_Activities/Operations/gse/Flight_Dynamics


Images, Animation, Video, Text, Credits; ESA/NASA/ATG Medialab.


Best regards, Orbiter.chArchive link


Powering the future with lunar soil


ESA — European Space Agency patch.


18 July 2019


Building a lunar base would be one of the next logical steps in our exploration of the Solar System, but the survival of a future crew depends on access to a reliable source of energy. An ESA Discovery & Preparation study explored how lunar regolith – the dust, soil and rock on the Moon’s surface – could be used to store heat and provide electricity for future astronauts, rovers and landers.



Future Moon base

Humans would have little difficulty reaching the Moon’s surface with today’s technology, but it is expensive – sometimes even impossible – to take all the materials we would need with us, especially if we want to stay for more than a couple of days. For sustainable, long-term exploration, we should instead look to local resources available at the destination. As part of this endeavour, Discovery & Preparation recently supported aerospace experts Azimut Space (formerly Sonaca Space) to investigate whether it would be possible to create ‘heat-storage bricks’ out of lunar regolith.



Moon base

In space, energy typically comes via solar panels that provide almost instantaneous electricity when the Sun shines on them. But inhabitants of the Moon could expect to spend up to 16 days in darkness during the lunar night. Finding a sustainable energy solution that collects sunlight during the long lunar days and stores it for use at night is essential to make the prospect of long-term lunar habitation a reality.


Regolith bricks offer a way of storing daytime solar energy so that electricity can be produced at night; this would be vital for any humans living and working on the Moon. The stored heat could also be released directly to keep robotic equipment warm enough to function during the long hours of darkness.


«Apollo astronauts brought back small amounts of Moon rock, allowing us to create very similar ‘fake’ lunar regolith here on Earth,» explains Aidan Cowley from ESA’s Human Spaceflight and Robotic Exploration Directorate, who oversaw the project. «In this study, we used Earth rock with comparable properties to Moon rock, crushed into a powder until the particles matched the size of those in the lunar regolith.»



Homemade regolith brick, 14 cm long.

After making this powder into a brick, the team pumped energy into their imitation lunar regolith to see how well it could store heat. They also connected it to a heat engine to create electricity using the energy stored inside it.


«Any Moon-based technology would face incredibly tough conditions – long nights, temperatures ranging from -173°C to 127°C and extremely low pressures,» explains Project Manager Luca Celotti from Azimut Space. «We mimicked these conditions as best as we could to create a ‘Moon-like’ environment for our brick.»



Image above: The artificial regolith brick inside a vacuum chamber, which simulated the low pressures and extreme temperatures that astronauts and technology would face.


«Using lunar regolith to store heat on the Moon would provide us with an abundance of readily-available material meaning space travellers wouldn’t need to take much from Earth. Eventually, this will enable more ambitious space missions to go ahead.»


As the imitation regolith worked well, the team would next like to make the process more efficient and scale it up to further investigate whether regolith bricks would be capable of producing the energy that would be required.



Image above: A 1.5 tonne building block of artificial lunar regolith, demonstrating 3D printing using lunar soil.


«This is just the first step towards creating an innovative and sustainable method of heat storage and electricity generation that could make it possible for us to land on the Moon,» concludes Luca.


Using local materials helps us move into sustainable, permanent exploration, giving rise to cheaper, safer and easier access to space. And lunar regolith would not only be useful for heat storage and electricity generation. This material – plentiful on the Moon – could also be used to build future habitats, as a source of oxygen or minerals, and even to make everyday objects such as tools.


Related links:


Making bricks from Moon dust: http://www.esa.int/Our_Activities/Human_and_Robotic_Exploration/Exploration/Bricks_from_Moon_dust


3D printing our way to the Moon: http://www.esa.int/Our_Activities/Preparing_for_the_Future/Discovery_and_Preparation/3D_printing_our_way_to_the_Moon


Study on solar 3D printing of lunar regolith: https://www.esa.int/gsp/ACT/coffee/2018-04-12-isru.html


How to keep warm on the Moon: http://www.esa.int/Our_Activities/Preparing_for_the_Future/Discovery_and_Preparation/How_to_keep_warm_on_the_Moon


Azimut Space: http://www.azimutspace.com/


Human Spaceflight and Robotic Exploration: https://www.esa.int/About_Us/Ministerial_Council_2016/Human_Spaceflight_and_Robotic_Exploration_Programmes


Images, Text, Credits: ESA/RegoLight, visualisation: Liquifer Systems Group, 2018/Azimut Space.


Greetings, Orbiter.chArchive link


2019 July 18 Shadowed Moon and Mountain Image Credit: Norbert…


2019 July 18


Shadowed Moon and Mountain
Image Credit: Norbert Span


Explanation: On July 16 the Moon celebrated the 50th anniversary of the launch of Apollo 11 with a lunar eclipse visible from much of planet Earth. In this view part of the lunar disk is immersed in Earth’s dark, reddened umbral shadow. Near the maximum eclipse phase, it just touches down along a mountain ridge. The rugged Tyrolean nightscape was recorded after moonrise south of Innsbruck, Austria with a dramatically lit communication tower along the ridgeline. Of course eclipses rarely travel alone. This partial lunar eclipse was at the Full Moon following July 2nd’s New Moon and total eclipse of the Sun.


∞ Source: apod.nasa.gov/apod/ap190718.html


Global25 workshop 4: a neighbour joining tree

Phylogenetic trees are easy to produce, but there’s an infinite number of ways to run them, and, depending on the input data you’re using, some methods are a lot more effective than others. In this tutorial I’m going to demonstrate one method that has worked well for me when looking at the fine scale genetic relationships between ancient and present-day human populations with my Global25 data.
To get started 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 > Clustering > Neighbour joining. Here’s a screen cap of me doing just that…



Then, from the tabs on the right, choose Chord as the similarity index and MAR_Iberomaurusian, the most distinct unit in the datasheet, as the root. PAST offers an exceptionally large range of similarity indices and they generally produce similar results, but, in my experience, Chord creates among the most visually pleasing outcomes when dealing with fine scale genetic substructures.



This is the tree you should see after exporting the image via the graph settings tab in PAST, and, if you like, rotating it 90 degrees with an image editing software of your choice. Note the fairly substantial differences between the populations from Northwestern Europe, which are often difficult to tease apart in such analyses.



If you have your own Global25 coordinates you can add them to my PAST-compatible datasheet to see where you cluster in this tree. And, of course, you can design your own PAST-compatible datasheets and trees with any combination of populations and/or individuals from the Global25 text files at the links below. It’s easy; just copy paste the coordinates of your choice into an empty text file, open it with PAST and then save it with the dat extension to create a new PAST datasheet. But make sure never to mix up the scaled and non-scaled coordinates.



Global25 datasheet (scaled)
Global25 pop averages (scaled)
Global25 datasheet
Global25 pop averages



An important point to keep in mind when running these sorts of analyses is that PAST and other such programs need enough genetic differentiation to latch onto in order to produce meaningful results. Thus, even when studying the relationships between very closely related populations, it’s not just useful to include a root population or individual, but also some near and far related groups to help the analysis algorithm flesh out the key genetic substructures.
To be honest, I don’t really know whether using the Chord index and rooting the tree with MAR_Iberomaurusian is the best way to run a neighbour joining tree analysis of ancient and present-day West Eurasian genetic variation. What do you think? Feel free to let me know in the comments.
See also…
Global25 workshop 1: that classic West Eurasian plot
Global25 workshop 2: intra-European variation
Global25 workshop 3: genes vs geography in Northern Europe
The South Asian cline that no longer exists
Getting the most out of the Global25
Genetic ancestry online store (to be updated regularly)

Source


Viking invasion at bioRxiv

A new preprint featuring hundreds of Viking Age genomes has appeared at bioRxiv [LINK]. Titled Population genomics of the Viking world, it looks like a solid effort overall, although I’m skeptical about its conclusions. I might elaborate on that in the comments below, but I’ll have a lot more to say on the topic if and when I get to check out the ancient genomes with my own tools. Details about the new samples, including their Y-chromosome haplogroup assignments, are available here. Below is the abstract, emphasis is mine:



The Viking maritime expansion from Scandinavia (Denmark, Norway, and Sweden) marks one of the swiftest and most far-flung cultural transformations in global history. During this time (c. 750 to 1050 CE), the Vikings reached most of western Eurasia, Greenland, and North America, and left a cultural legacy that persists till today. To understand the genetic structure and influence of the Viking expansion, we sequenced the genomes of 442 ancient humans from across Europe and Greenland ranging from the Bronze Age (c. 2400 BC) to the early Modern period (c. 1600 CE), with particular emphasis on the Viking Age. We find that the period preceding the Viking Age was accompanied by foreign gene flow into Scandinavia from the south and east: spreading from Denmark and eastern Sweden to the rest of Scandinavia. Despite the close linguistic similarities of modern Scandinavian languages, we observe genetic structure within Scandinavia, suggesting that regional population differences were already present 1,000 years ago. We find evidence for a majority of Danish Viking presence in England, Swedish Viking presence in the Baltic, and Norwegian Viking presence in Ireland, Iceland, and Greenland. Additionally, we see substantial foreign European ancestry entering Scandinavia during the Viking Age. We also find that several of the members of the only archaeologically well-attested Viking expedition were close family members. By comparing Viking Scandinavian genomes with present-day Scandinavian genomes, we find that pigmentation-associated loci have undergone strong population differentiation during the last millennia. Finally, we are able to trace the allele frequency dynamics of positively selected loci with unprecedented detail, including the lactase persistence allele and various alleles associated with the immune response. We conclude that the Viking diaspora was characterized by substantial foreign engagement: distinct Viking populations influenced the genomic makeup of different regions of Europe, while Scandinavia also experienced increased contact with the rest of the continent.





Margaryan et al., Population genomics of the Viking world, bioRxiv, posted July 17, 2019, doi: https://doi.org/10.1101/703405
See also…
They came, they saw, and they mixed
Who were the people of the Nordic Bronze Age?
Genetic and linguistic structure across space and time in Northern Europe

Source


50 years ago, three Apollo astronauts rode this 363 foot tall…


50 years ago, three Apollo astronauts rode this 363 foot tall rocket, the Saturn V, embarking on one of the greatest missions of mankind – to step foot on another world. On July 20, 1969, astronauts Buzz Aldrin, Michael Collins and Neil Armstrong made history when they arrived at the Moon. Thanks to the Saturn V rocket, we were able to complete this epic feat, returning to the lunar surface a total of six times. The six missions that landed on the Moon returned a wealth of scientific data and almost 400 kilograms of lunar samples. 


In honor of this historic launch, the National Air and Space Museum is projecting the identical rocket that took our astronauts to the Moon on the Washington Monument in Washington, D.C.


This week, you can watch us salute our Apollo 50th heroes and look forward to our next giant leap for future missions to the Moon and Mars. Tune in to a special two-hour live NASA Television broadcast at 1 p.m. ET on Friday, July 19. Watch the program at www.nasa.gov/live.


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


NASA Releases Stunning Panoramas of Apollo Landing Sites for 50th Anniversary


NASA — Apollo 17 Mission patch.


July 17, 2019


NASA imagery experts at NASA’s Johnson Space Center have “stitched together” images from the Apollo landings sites on the Moon for a 50th anniversary reminder of what the 12 humans who walked on its surface experience visually.



(click on the image for enlarge)

Individual images taken by the Apollo astronauts were pulled together by NASA imagery specialist Warren Harold at Johnson, and the accuracy of the unique perspective they represent was verified by  Apollo 17 astronaut Harrison “Jack” Schmitt, the only geologist to walk on the Moon.


«The Valley of Taurus-Littrow on the Moon presents a view that is one of the more spectacular natural scenes in the Solar System,” Schmitt said about the images stitched together from his Moon base Station 5 at the Taurus-Littrow landing site.


“The massif walls of the valley are brilliantly illuminated by the Sun, rise higher than those of the Grand Canyon, and soar to heights over 4,800 feet on the north and 7,000 feet on the south,” Schmitt added. “At the same time, the summits are set against a blacker than black sky —  a contrast beyond the experience of visitors from Earth. And, over the South Massif wall of the valley, one can always see home, the cloud-swirled blue Earth, only 250,000 miles away.»


The Apollo 17 panorama also has been converted into an immersive panorama viewable on the NASA Johnson account on Facebook.


Inspect these images and learn more about the sites they depict at:


https://images.nasa.gov/


https://flic.kr/s/aHsjHYKZe3


Immerse yourself in the view from the Apollo 17 landing site by visiting JSC Facebook at:


https://go.nasa.gov/2YXLtbh


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


Apollo 17: https://www.nasa.gov/mission_pages/apollo/apollo-17


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


Greetings, Orbiter.chArchive link


Advanced Science Gear Work Ahead of Vehicle Rush Hour at Station


ISS — Expedition 60 Mission patch.


July 17, 2019


Three Expedition 60 crewmates aboard the International Space Station spent the day servicing a variety of research hardware. Back on Earth, three different rockets are preparing to replenish the orbiting lab with a new crew and more science and supplies.


NASA astronauts Christina Koch and Nick Hague have been working on an array of science gear today supporting numerous advanced microgravity experiments.


Koch installed the HERMES facility researching the dynamics of asteroid and planetary surfaces with no atmospheres. She then checked out the Photobioreactor that explores microalgae as a means to support hybrid life support systems.



Image above: The Earth’s limb and the atmospheric glow highlight the thin blue atmosphere back lit by the Sun’s rays during a period between night and day. The light of the moon and the starry Milky Way drape the background as the International Space Station orbited 257 miles above the Pacific Ocean between Hawaii and Mexico. Image Credit: NASA.


Hague was over in the Kibo laboratory module this morning configuring backup software for the Japanese robotic arm that maneuvers external experiments. After lunch, Hague replaced gear inside the Combustion Integrated Rack to support safe flame and fuel research in space.


The orbiting laboratory is gearing up for a high traffic period at the end of July. Two new Russian spaceships and a U.S. cargo craft will be occupying three different ports bringing the station crew up to full speed.


Saturday will see the launch and arrival of three new Flight Engineers aboard the Soyuz MS-13 crew ship. Astronauts Drew Morgan and Luca Parmitano and cosmonaut Alexander Skvortsov will lift off Saturday at 12:28 p.m. EDT from Kazakhstan and dock to the Zvezda service module at 6:50 p.m.



International Space Station (ISS). Animation Credit: NASA

Next, the SpaceX Dragon resupply ship is scheduled to launch from Florida at Sunday at 7:35 p.m. Hague and Koch will be at the helm of the robotics workstation in the cupola to capture Dragon on Tuesday at 11 a.m. with the Canadarm2 robotic arm.


Finally, Russia’s Progress 73 (73P) space freighter will replace the Progress 72 when it departs the Pirs docking compartment July 29. The 73P is due to blast off July 31 on a short two-orbit trip before automatically docking to Pirs with food, fuel and supplies for the station inhabitants.


Related links:


Expedition 60: https://www.nasa.gov/mission_pages/station/expeditions/expedition60/index.html


HERMES: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7732


Photobioreactor: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7426


Kibo laboratory module: https://www.nasa.gov/mission_pages/station/structure/elements/japan-kibo-laboratory


Combustion Integrated Rack: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=317


High traffic period: https://www.nasa.gov/launchschedule/


Zvezda service module: https://www.nasa.gov/mission_pages/station/structure/elements/zvezda-service-module.html


Canadarm2 robotic arm: https://www.nasa.gov/mission_pages/station/structure/elements/mobile-servicing-system.html


Progress 72: https://go.nasa.gov/2IaDAKd


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


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


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


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


Best regards, Orbiter.chArchive link


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