суббота, 18 августа 2018 г.

Archaeologists start work to reveal Sheffield’s lost medieval castle

A team of archaeologists is set to reveal the lost remains of Sheffield Castle as part of a project that could be used to help regenerate part of the city. The dig is a central aspect of the City Council’s ‘Castlegate Kickstart’ project to help boost the city’s ancient heart.











Archaeologists start work to reveal Sheffield’s lost medieval castle
Excavations at the Sheffield castle site [Credit: University of Sheffield]

The excavations, led by Sheffield-based Wessex Archaeology North in collaboration with students and staff from the Department of Archaeology, University of Sheffield, are designed to recover and assess a key element in the city’s forgotten medieval heritage.


Findings from the excavations, which are now underway, are set to inform a collaboration between the University of Sheffield, Sheffield City Council and the Friends of Sheffield Castle to inspire regeneration of the city’s Castlegate Quarter.


Ongoing work by the University’s Department of Archaeology has revealed the history behind the castle, and a book on their findings will be published next year, while students from the University’s School of Architecture have developed designs for the use of the site to attract business, investment and tourism to the area.











Archaeologists start work to reveal Sheffield’s lost medieval castle
Reconstruction of the castle’s Gatehouse [Credit: University of Sheffield]

Andrew Norton, Regional Director of Wessex Archaeology North, who are conducting the excavations, said: “Wessex Archaeology is delighted to be working with the University of Sheffield on the Castlegate site. With student volunteers assisting our team, the project will be a valuable opportunity to experience commercial archaeology and working with the public first hand.


“Specialists from the University of Sheffield will provide expert input on the history of the site and the flora and faunal assemblages. Wessex Archaeology is very much looking forward to combining the best of two great organisations for the benefit of this historic site.”


Research on the origins of the castle together with findings from earlier excavations are also being used to create a virtual reality experience, which will give people the opportunity to ‘see’ how the castle looked for the first time in almost 400 years.


The VR experience is being developed by Sheffield-based creative agency Human with archaeologists, architects and computer scientists from the University, and is funded by the Arts and Humanities Research Council and the Engineering and Physical Sciences Research Council. The Principal Investigator on this project is the Head of the Department of Archaeology at the University, Professor Dawn Hadley, who said: “This is an exciting initiative that will bring the castle back to life, showing not just what the Castlegate district looked like in the Middle Ages but also inspiring ideas for the regeneration of the site”.


Professor John Moreland, who leads the Castlegate project at the University of Sheffield, said: “We’re delighted that the next phase of our research into Sheffield Castle is set to start this week. We’ve known about some of the history of the castle and its role in medieval England for quite some time now, but what we don’t know is how much more of it remains on the castle’s site.


“The Castlegate Quarter of Sheffield is due for regeneration, and we believe that the presence of the castle increases the attractiveness of the site for developers. Our work with Wessex North, Sheffield City Council and the Friends of Sheffield Castle to look for further remains will mean that the city can use the area’s heritage to plan for its future.”



Sheffield Castle was once one of the grandest and most powerful in the north of medieval England. It was home to some of the great families at the time – including the de Furnivals, Nevils, Shrewsburys and Howards.


Mary Queen of Scots was held prisoner there for 14 years between 1570 and 1584, before she was executed in 1587. The castle was then destroyed by Parliament following the Civil War in 1646.


For more information on the history of Sheffield Castle and what has been found so far, visit: https://www.sheffield.ac.uk/archaeology/news/sheffield-castle-1.666864


Source: The University of Sheffield [August 15, 2018]



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Why war is a man’s game

No sex differences in attitudes or abilities are needed to explain the near absence of women from the battlefield in ancient societies and throughout history, it could ultimately all be down to chance, say researchers at the University of St Andrews.











Why war is a man’s game
Credit: University of St Andrews

The findings, published in Proceedings of the Royal Society of London Series B, have implications for our understanding of the origin of war and violence-related psychological disorders.


Led by Alberto Micheletti, a PhD researcher in the University’s School of Biology, the research team used evolutionary models to investigate why almost-exclusively men have gone to war, until very recent times.


The mathematical analysis considered how male participation and female participation in war evolve over time, showing that they can influence each other. Previous hypotheses have suggested that male-only war is the result of fundamental differences between the sexes, for example men being on average stronger and thus more effective in war.


Mr Micheletti said: “Our study shows that these differences are not needed to explain why women generally don’t go to war. We found that the more one sex participates in warfare, the less the other sex is incentivised to do so. Over time, this leads to only one sex fighting in battle.”


But why male-only war rather than female-only war? Mr Micheletti continued: “It all depends on what behaviours were dominant in ancestral human populations. An initial male-bias in participation in war would have encouraged more men to fight – eventually leading to male-only war parties.


“Ultimately it could all be down to chance. Had women been more aggressive at the time when war first evolved, they could have been the warring sex. This is observed in other species: for example, in spotted hyenas, only females attack other packs. But, in our own species, this was not the case.”


The research suggested that male-male competition over opportunities for reproduction, an aspect of what biologists call ‘sexual selection’, might have caused men to be generally more aggressive in other contexts, and this might have been enough for more men than women to initially go to war. Greater strength and effectiveness in battle, together with other sex differences, may have reinforced this pattern.


Mr Micheletti added: “In this way, the target of male aggression changed from members of their own group, to men from other groups – and resulted in raids or battles aimed at securing additional resources or mating partners from further afield.”


This point can contribute to explaining why psychotic-type violence disorders affect predominantly men. So far, such disorders have been considered the consequence of genetic errors affecting aggressive behaviours aimed at group-mates. But this new study suggests that they may originate from aggression targeted at other groups, such as participation in warfare.


The fact that only men go to war might mean that genetic mutations leading to pathological disorders affect them exclusively.


Mr Micheletti concluded: “Asking a simple question about a basic sex difference in human behaviour helped us understand the origins of warfare and the ways in which our ancestral past may still – at least in part – affect us today.”


Author: Christine Tudhope | Source: University of St Andrews [August 16, 2018]



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3,000-year-old footprint found in eastern Turkey

An ancient human footprint belonging to a civilization from 3,000 years ago has been uncovered at a castle in the southeastern province of Van.











3,000-year-old footprint found in eastern Turkey
Credit: AA

Erkan Konyar, an ancient history professor at Istanbul University History, told state-run Anadolu Agency the 26-centimeter-long footprint, which fit a modern shoe size 36, was found at the Van Castle and belonged to a noble. The area around Van is noted for Urartu ruins.


“We can identify the structure of the footprint after examinations. The footprint was cut and removed from its place. Following the examinations, it will be delivered to a museum. It has a very important moral meaning because it belongs to the Urartians,” said Konyar, adding that the footprint would be examined by anthropologists.


For the first time, the excavations, which have been ongoing since 2015, have found a mark made by a human in the region, he added.


Van, which was the capital of the Urartian kingdom in the ninth century BC, has often been called “the Pearl of the East” because of the beauty of its surrounding landscape.


It is located on the eastern shore of Lake Van, the largest lake in Turkey, and is also home to Van Castle.


Source: Anadolu Agency [August 16, 2018]



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Roman-era tombs discovered in Palestinian city of Hebron

A set of Roman-era tombs dating back some 2,000 years have been discovered near the Palestinian city of Hebron in the occupied West Bank during road works, an official said Thursday.











Roman-era tombs discovered in Palestinian city of Hebron
The rock-cut tombs from the Roman-era which were discovered during construction of a new road in Idna village,
northwest the West Bank city of Hebron [Credit: AFP/Hazem Bader]

The cemetery dating to the first century AD, when the region was under Roman rule, was found in the village of Idna in the southern West Bank around two weeks ago.
It was discovered during road work in mountainous terrain in the area, said Taleb Jubran, director of the department of tourism and antiquities in Hebron.











Roman-era tombs discovered in Palestinian city of Hebron
Taleb Jubran, director of the department of tourism and antiquities in Hebron, points to a Roman-era
burial site discovered near the West Bank city of Hebron [Credit: AFP/Hazem Bader]

Bones, pottery and some 32 tombs set into stone were found. It was clear to archaeologists that artifacts had been stolen from the site before it was officially discovered, said Jubran.
“This discovery is very important for us to study it and to preserve it,” Jubran said.


The tombs were set out over a space of some 50 metres.











Roman-era tombs discovered in Palestinian city of Hebron
Taleb Jubran, director of the department of tourism and antiquities in Hebron, points to a Roman-era
burial site discovered near the West Bank city of Hebron [Credit: AFP/Hazem Bader]

Officials also hoped to turn the site into a tourist attraction, while further study of it would continue to turn up details of what was found and its importance, he said.


A large number of remains from the Roman era can be found and visited in Israel and the Palestinian territories as well as the region as a whole.


Source: AFP [August 16, 2018]



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3,800-year-old wall relief unearthed in Peru

Archaeologists discovered an ancient wall relief in Peru, belonging to the oldest civilizations in the Americas, news agency Andina reported on Thursday. The wall is approximately 3,800 years old and portrays snakes and human heads.











3,800-year-old wall relief unearthed in Peru
A handout photo made available by the Archaeological Zone of Caral shows a new wall with reliefs of some
3,800 years old, which has been discovered in the ruins of Vichama, Peru [Credit: EPA]

One metre (3.2 feet) high and 2.8 meters long, the wall relief was discovered in the sea-side archaeological site of Vichama, 110 kilometres (68 miles) north of Peru’s capital, Lima.


The Vichama site is one of the excavation points of the recently discovered Caral civilization, also known as Norte Chico, and has been explored by archaeologists since 2007.


The Caral civilization is 5,000 years old, making it the oldest civilization in the Americas, and flourished at the same time as the thriving Mesopotamian, Egyptian and Chinese civilizations. The Caral people lived in the Supe Valley along the north-central coast of Peru.


Dating back to 1800 and 3500 BC, Vichama is thought to have been a fishing community and one of the Caral peoples’ various cities. The wall was made of adobe, a clay-like material from which bricks are made and was located at the entry point of a ceremonial hall.


The wall relief shows four human heads, side by side, their eyes closed, with two snakes passing between and around them. The snakes point their heads to what appears to be a humanoid seed symbol that is digging into the soil.


Archaeologist Ruth Shady, who oversees the site and announced the discovery, hypothesized that the serpents represent a water deity that irrigates the earth and makes seeds grow.


Shady said the relief was likely done towards the end of a drought and famine that the Caral civilization experienced. Other reliefs discovered nearby showed emaciated humans.


Archaeologists believe that the relief discovery reinforces the notion that these early humans were attempting to depict the difficulties they faced due to climate change and water scarcity, which had a large impact on their agricultural production.


The Caral excavation site has so far unearthed the ruins of 22 buildings in a 25-hectare space, dating back to between 1800 and 1500 BC.


Source: Deutsche Welle [August 17, 2018]



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1,800-year-old tomb with reliefs of Herakles discovered in Crimea

An ancient Greek tomb was discovered in Crimea at the Kyz-Avul necropolis, near the city of Kerch, a representative of the archaeology fund, Oleg Markov, told Sputnik Friday.











1,800-year-old tomb with reliefs of Herakles discovered in Crimea

Credit: Oleg Markov/FB



According to the historian Nikolai Fedoseev, whose expedition discovered the tomb, it belongs to the 2nd century AD and is decorated with various reliefs, including a depiction of the hero Herakles.
Although the tomb had already been pillaged, the reliefs, as well as a few ritual objects, remained untouched. The tomb was built by Greek colonists who first settled in Crimea almost 2,500 years ago.


Source: Sputnik News [August 17, 2018]



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Gamer Mice Perched on a polystyrene ball, a mouse enters a…


Gamer Mice


Perched on a polystyrene ball, a mouse enters a virtual gaming world. It makes its way through the patterned rooms of this strange new world, in search of rewards in the shape of cookies and other food. But this is no ordinary rodent game. While the mouse explores this new environment, a team of scientists are recording how the cells in its brain are behaving. Over several days of gaming, the scientists are able to see what happens to the mouse’s brain cells as new memories of this virtual world are formed. In one brain area, the hippocampus, new memories of this world are being mapped. This image shows the same cells flashing red each time the mouse reaches a particular region of the virtual world. By mapping space and time to individual brain cells, this study helps us to better understand how our memories are formed.


Written by Gaëlle Coullon



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The Grey Cairns of Camster, The Highlands, Scotland, 18.8.18.


The Grey Cairns of Camster, The Highlands, Scotland, 18.8.18.


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Meteor Activity Outlook for August 4-10, 2018

This brilliant alpha Capricornid fireball was captured by Brad Goldpaint from near Indepencence, CA, USA on July 21, 2018 at 09:21 Universal Time. © Brad Goldpaint https://goldpaintphotography.com/

Meteor activity kicks into high gear in August as seen from the northern hemisphere. The main reason for all this activity is the Perseid shower that peaks on August 13th. This shower is active most of the month and remains above the level of the sporadic background for a week centered on August 13th. The sporadic activity is also near maximum as seen from the northern hemisphere and is now more than double the rates from just three months ago. As seen from southern hemisphere, meteor rates are still decent but falling rapidly. The sporadic rates continue their downward slide and the Perseid radiant does not rise high into the sky as seen in the southern hemisphere. So rates for the Perseids are greatly reduced when compared to those seen from the northern hemisphere.


During this period the moon will reach its last quarter phase on Saturday August 4th. This is good for evening observations but once the moon rises during the early morning hours, conditions will be less than ideal. These conditions improve with each passing night to where there is little lunar interference at the end of this period. The estimated total hourly meteor rates for evening observers this week is near 4 as seen from mid-northern latitudes and also 3 for those viewing from subtropical southern latitudes (25S). For morning observers the estimated total hourly rates should be near 20 for those viewing from mid-northern latitudes and also 18 for those viewing from subtropical southern latitudes (25S). The actual rates will also depend on factors such as personal light and motion perception, local weather conditions, alertness and experience in watching meteor activity. Rates are reduced during the morning hours due to moonlight. Note that the hourly rates listed below are estimates as viewed from dark sky sites away from urban light sources. Observers viewing from urban areas will see less activity as only the brighter meteors will be visible from such locations.


The radiant (the area of the sky where meteors appear to shoot from) positions and rates listed below are exact for Saturday night/Sunday morning August 4/5. These positions do not change greatly day to day so the listed coordinates may be used during this entire period. Most star atlases (available at science stores and planetariums) will provide maps with grid lines of the celestial coordinates so that you may find out exactly where these positions are located in the sky. A planisphere or computer planetarium program is also useful in showing the sky at any time of night on any date of the year. Activity from each radiant is best seen when it is positioned highest in the sky, either due north or south along the meridian, depending on your latitude. It must be remembered that meteor activity is rarely seen at the radiant position. Rather they shoot outwards from the radiant so it is best to center your field of view so that the radiant lies near the edge and not the center. Viewing there will allow you to easily trace the path of each meteor back to the radiant (if it is a shower member) or in another direction if it is a sporadic. Meteor activity is not seen from radiants that are located far below the horizon. The positions below are listed in a west to east manner in order of right ascension (celestial longitude). The positions listed first are located further west therefore are accessible earlier in the night while those listed further down the list rise later in the night.





Radiant Positions at 22:00 LDT


Radiant Positions at 22:00

Local Daylight Saving Time






Radiant Positions at 01:00 LDT


Radiant Positions at 0100

Local Daylight Saving Time






Radiant Positions at 4:00 LDT


Radiant Positions at 04:00

Local Daylight Saving Time





These sources of meteoric activity are expected to be active this week.


The first of the kappa Cygnids (KCG) should appear late next week from a radiant located near 18:40 (280) +45. This area of the sky lies in northern Lyra, 6 degrees northeast of the brilliant zero magnitude star known as Vega (alpha Lyrae). This radiant is best laced near 2300 Local Daylight Saving Time (11pm), when it lies on the meridian and is located highest in the sky. With an entry velocity of 21 km/sec., the average meteor from this source would be of slow velocity.


The alpha Capricornids (CAP) are active from July 3 through August 11 with maximum activity occurring during the last week of July. The broad maximum occurs anywhere from July 25 to the 30th with visual rates usually around 3 per hour. The radiant is currently located at 20:42 (310) -08, which places it in western Aquarius, 2 degrees northwest of the 4th magnitude star known as Albali (epsilon Aquarii). This radiant is best placed near 0100 LDT, when it lies on the meridian and is located highest in the sky. With an entry velocity of 22 km/sec., the average alpha Cap meteor would be of slow velocity.


The center of the large Anthelion (ANT) radiant is currently located at 21:40 (325) -14. This position lies in northeastern Capricornus, 2 degrees northwest of the 3rd magnitude star known as Deneb Algedi (delta Capricorni). Due to the large size of this radiant, Anthelion activity may also appear from western Aquarius as well as Capricornus. This radiant is best placed near 0200 LDT, when it lies on the meridian and is located highest in the sky. Hourly rates at this time should be near 2 as seen from mid-northern latitudes and 3 as seen from tropical southern latitudes. With an entry velocity of 30 km/sec., the average Anthelion meteor would be of medium-slow velocity.


The Northern delta Aquariids (NDA) are active from July 23 through August 27. The radiant is currently located at 22:36 (339) -01. This position is located in northern Aquarius, 1 degree south of the 4th magnitude star known as eta Aquarii. Maximum activity is not expected until August 14, so hourly rates will low at this time. The radiant is best placed near 0300 LDT, when it lies highest in the sky. With an entry velocity of 38 km/sec., these meteors would be of medium velocities. This shower seems to be a continuation of the Northern June Aquilids, which had been active since early June.


The Southern Delta Aquariids (SDA) are active from a radiant located at 23:04 (346) -14. This position is located in central Aquarius, 3 degrees northeast of the 3rd magnitude star known as Skat (delta Aquarii). Hourly rates are still decent with observers in the northern hemisphere seeing 2-5 per hour and those south of the equator seeing 5-10 per hour.  The radiant is best placed near 0300 LDT, when it lies highest in the sky. With an entry velocity of 41 km/sec., most activity from this radiant would be of average velocities.


The Piscids Austrinids (PAU) are an obscure shower, not well seen from the northern hemisphere. Recent studies by the IMO Video Network shows no activity at all. Other studies have indicated that this shower is active later than previously thought. We will go along with that idea until more information is available. It is now thought that this radiant is active from July 30 through August 18, with maximum activity occurring on the 8th. Using these parameters, the current position of the radiant would be 23:18 (350) -22. This area of the sky is located in southern Aquarius, 8 degrees northeast of the bright 1st magnitude star known as Fomalhaut (alpha Piscis Austrini). The radiant is best placed near 0300 LDT, when it lies highest in the sky. Current rates would most likely be less than 1 per hour, no matter your location. With an entry velocity of 44km/sec., most activity from this radiant would be of average velocities.


The Perseids (PER) are active from a radiant located at 02:26 (037) +56. This position lies in extreme northwestern Perseus, 4 degrees west of the 4th magnitude star known as Miram (eta Persei). This area of the sky is best placed for viewing during the last dark hour before dawn when it lies highest in the sky. Maximum is not until August 13 so current rates are expected to be near 5 per hour as seen from the northern hemisphere and 2 as seen from south of the equator. Unfortunately these meteors are not well seen from the southern hemisphere. With an entry velocity of 59 km/sec., the average meteor from this source would be of swift velocity.


The eta Eridanids (ERI) were discovered by Japanese observers back in 2001. Activity from this stream is seen from July 23 though September 17 with maximum activity occurring on August 11. The radiant currently lies at 02:36 (039) -14, which places it in eastern Cetus, 2 degrees west of the 4th magnitude star known as pi Ceti. This area of the sky is best seen during the last dark hour before dawn when the radiant lies highest in a dark sky. Current rates are expected to be less than 1 per hour as seen from the northern hemisphere and near 1 per hour as seen from south of the equator. With an entry velocity of 65 km/sec., the average meteor from this source would be of swift velocity.


The 49 Andromedids (FAN) were discovered by Željko Andreić et al of the Croatian Meteor Network, using databases from SonotaCo, 2013 and CMN, 2013). These meteors are active from July 6 through August 14 with maximum activity occurring on July 21. The current position of the radiant is 02:46 (041) +54. This position lies in extreme northwestern Perseus, only 1 degree west of the 4th magnitude star known as tau Persei. This location is very close to the Perseid radiant and care must be taken to distinguish between these two sources. The Perseids are expected to be far more numerous during this period. This area of the sky is best placed for viewing during the last dark hour before dawn when it lies highest in the sky. Rates are currently expected to be less than 1 per hour no matter your location. With an entry velocity of 60 km/sec., the average 49 Andromedid meteor would be of swift velocity.


The last of the psi Cassiopeiids (PCA) are expected this week. These meteors are active from July 5 through August 7 with maximum activity occurring on July 22. The current position of the radiant is 03:54 (059) +78. This position lies in a remote are of northwestern Camelopardalis, 8 degrees northeast of the faint star known as 50 Cassiopeiae. This area of the sky is best placed for viewing during the last dark hour before dawn when it lies highest in the sky. Rates are currently expected to be less than 1 per hour no matter your location. With an entry velocity of 42 km/sec., the average psi Cassiopeiid meteor would be of medium speed.


As seen from the mid-northern hemisphere (45N) one would expect to see approximately 10 sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near 3 per hour. As seen from the tropical southern latitudes (25S), morning rates would be near 7 per hour as seen from rural observing sites and 2 per hour during the evening hours. Morning rates are reduced during this period due to moonlight. Locations between these two extremes would see activity between the listed figures.


The list below offers the information from above in tabular form. Rates and positions are exact for Saturday night/Sunday morning except where noted in the shower descriptions.

















































































































SHOWER DATE OF MAXIMUM ACTIVITY CELESTIAL POSITION ENTRY VELOCITY CULMINATION HOURLY RATE CLASS
RA (RA in Deg.) DEC Km/Sec Local Daylight Saving Time North-South
kappa Cygnids (KCG) Aug 13 18:40 (280) +45 21 23:00 <1 – <1 II
alpha Capricornids (CAP) Jul 27 20:42 (310) -08 22 01:00 2 -2 II
Anthelions (ANT) 21:40 (325) -14 30 02:00 1 – 2 III
Northern delta Aquariids (NDA) Aug 14 22:36 (339) -01 38 03:00 <1 – <1 IV
Southern delta Aquariids (SDA) Jul 30 23:04 (346) -14 41 04:00 2 – 3 I
Piscids Austrinids (PAU) Aug 08 23:18 (350) -22 44 04:00 <1 – 1 IV
Perseids (PER) Aug 13 02:26 (037) +56 59 06:00 5 – 2 I
eta Eridanids (ERI) Aug 11 02:36 (039) -14 65 06:00 1 – 1 IV
49 Andromedids (FAN) Jul 21 02:46 (041) +54 60 06:00 <1 – <1 IV
psi Cassiopeiids (PCA) Jul 22 03:54 (059) +78 42 07:00 <1 – <1 IV

Таинственные Геоглифы Намибия Африка

  Излучают сильнейшее биополе, влияющее на телепатическую взаимосвязь ДНК цепочек Source: Mysterious geoglyphs in Namibia, part one, circles in rocks by SpaceTrack https://rumble.com/embed/u7bmu.vgko6/ Source: Mysterious geoglyphs of Namibia, part 2, Spirals and Portals by SpaceTrack Source: Mysterious geoglyphs of Namibia, part 3, reticulated fields by SpaceTrack https://rumble.com/embed/u7bmu.vgksu/  
 ДНК со сходной  структурой способны узнавать друг друга без помощи белков и других биохимических соединений. К таким выводами приходят авторы исследования, опубликованного в Journal of Physical ChemistryПо мнению ученых, открытый ими механизм обеспечивает гомологическую рекомбинацию ДНК, играющую важную роль в эволюции биологических видов. Универсальный носитель наследственной информации, молекула ДНК, включает две цепочки пуриновых и пиримидиновых оснований, кодирующих последовательность аминокислот в белках. Неполовые клетки большинства живых организмов обладают двойным набором ДНК, состоящим из парных молекул со сходной (гомологичной) структурой. Сотрудники Имперского колледжа Лондона во главе с русским ученым профессором Алексеем Корнышевым изучали поведение молекул ДНК в растворе, очищенном от других органических соединений. Как выяснилось, цепочки ДНК сближались и взаимодействовали друг с другом, причем эти взаимодействия в два раза чаще наблюдались между гомологичными молекулами. Ранее считалось, что избирательные взаимодействия между гомологичными молекулами ДНК возможны только при участии белков и других химических соединений. Механизм «телепатической» связи между ДНК пока не объяснен, однако ученые предполагают, что эти крупные молекулы могут «опознавать» друг друга по распределению электрических зарядов. При этом вероятность такого опознавания возрастает по мере увеличения длины цепочек ДНК. По мнению исследователей, описанный ими механизм взаимодействия используется при гомологической рекомбинации – обмене генами между сходными молекулами ДНК. Этот процесс обеспечивает разнообразие генетических комбинаций внутри вида, он также важен для сохранения нормальной структуры ДНК при случайных повреждениях. Представление о базовом механизме гомологической рекомбинации позволит ученым лучше понять естественные механизмы защиты от мутаций и усовершенствовать методики генной инженерии и генной терапии. 24 января 2008 года

2018 August 18 Seeing Titan Image Credit: VIMS Team, U….


2018 August 18


Seeing Titan
Image Credit: VIMS Team, U. Arizona, ESA, NASA


Explanation: Shrouded in a thick atmosphere, Saturn’s largest moon Titan really is hard to see. Small particles suspended in the upper atmosphere cause an almost impenetrable haze, strongly scattering light at visible wavelengths and hiding Titan’s surface features from prying eyes. But Titan’s surface is better imaged at infrared wavelengths where scattering is weaker and atmospheric absorption is reduced. Arrayed around this centered visible light image of Titan are some of the clearest global infrared views of the tantalizing moon so far. In false color, the six panels present a consistent processing of 13 years of infrared image data from the Visual and Infrared Mapping Spectrometer (VIMS) on board the Cassini spacecraft. They offer a stunning comparison with Cassini’s visible light view.


∞ Source: apod.nasa.gov/apod/ap180818.html


Ardestie Earth House, nr. Dundee, Scotland, 16.8.18. I’m…










Ardestie Earth House, nr. Dundee, Scotland, 16.8.18.


I’m back in Scotland for a few days and I love the prehistoric sites here. Ardestie Earth House is great for providing you with a sense of how ancient communities shaped their own living conditions. This semi-subterranean settlement features a series of roundhouses and a soutterrain gallery that was likely used for either storage or defence. The stone gully down the centre of the long gallery was used for drainage.


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Large Fireball over Greenland

A Tweet from the Director of the Nuclear Information Project for the Federation of American Scientists, Hans Kristensen, on August 1, 2018 at 5:14 PM Washington D.C. time claimed that a, “Meteor explodes with 2.1 kilotons force 43 km above missile early warning radar at Thule Air Base (Ed. Greenland).”





Since then, the event has been confirmed by the JPL Center for NEO Studies (CNEOS) who computes high-precision orbits for Near-Earth Objects (NEOs) in support of NASA’s Planetary Defense Coordination Office.


NASA’s Jet Propulsion Laboratory confirmed “an object of unspecified size travelling at 24.4km/s struck earth in Greenland, just 43km (~28 miles) north of an early missile warning Thule Air Base on the 25th of July, 2018”. There was no public warning from the US government about the incident.



If you witnessed this event and/or if you have a video or a photo of this event, please

Submit an Official Fireball Report
(available in 36 languages here)


If you want to learn more about Fireballs: read our Fireball FAQ.



Prehistoric Hut Circles Video Footage, South Stack, Holy Island,…


Prehistoric Hut Circles Video Footage, South Stack, Holy Island, Anglesey, 14.8.18. (Silent Footage)


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Sprawling galaxy cluster found hiding in plain sight


An X-ray image (in blue) with a zoom in optical image (gold and brown) showing the central galaxy of a hidden cluster, which harbors a supermassive black hole. Image: Taweewat Somboonpanyakul


Bright light from black hole in a feeding frenzy had been obscuring surrounding galaxies


MIT scientists have uncovered a sprawling new galaxy cluster hiding in plain sight. The cluster, which sits a mere 2.4 billion light years from Earth, is made up of hundreds of individual galaxies and surrounds an extremely active supermassive black hole, or quasar.


The central quasar goes by the name PKS1353-341 and is intensely bright — so bright that for decades astronomers observing it in the night sky have assumed that the quasar was quite alone in its corner of the universe, shining out as a solitary light source from the center of a single galaxy.


But as the MIT team reports today in the Astrophysical Journal, the quasar’s light is so bright that it has obscured hundreds of galaxies clustered around it.


In their new analysis, the researchers estimate that there are hundreds of individual galaxies in the cluster, which, all told, is about as massive as 690 trillion suns. Our Milky Way galaxy, for comparison, weighs in at around 400 billion solar masses.


The team also calculates that the quasar at the center of the cluster is 46 billion times brighter than the sun. Its extreme luminosity is likely the result of a temporary feeding frenzy: As an immense disk of material swirls around the quasar, big chunks of matter from the disk are falling in and feeding it, causing the black hole to radiate huge amounts of energy out as light.


“This might be a short-lived phase that clusters go through, where the central black hole has a quick meal, gets bright, and then fades away again,” says study author Michael McDonald, assistant professor of physics in MIT’s Kavli Institute for Astrophysics and Space Research. “This could be a blip that we just happened to see. In a million years, this might look like a diffuse fuzzball.”


McDonald and his colleagues believe the discovery of this hidden cluster shows there may be other similar galaxy clusters hiding behind extremely bright objects that astronomers have miscatalogued as single light sources. The researchers are now looking for more hidden galaxy clusters, which could be important clues to estimating how much matter there is in the universe and how fast the universe is expanding.


The paper’s co-authors include lead author and MIT graduate student Taweewat Somboonpanyakul, Henry Lin of Princeton University, Brian Stalder of the Large Synoptic Survey Telescope, and Antony Stark of the Harvard-Smithsonian Center for Astrophysics.

Fluffs or points


In 2012, McDonald and others discovered the Phoenix cluster, one of the most massive and luminous galaxy clusters in the universe. The mystery to McDonald was why this cluster, which was so intensely bright and in a region of the sky that is easily observable, hadn’t been found before.


“We started asking ourselves why we had not found it earlier, because it’s very extreme in its properties and very bright,” McDonald says. “It’s because we had preconceived notions of what a cluster should look like. And this didn’t conform to that, so we missed it.”


For the most part, he says astronomers have assumed that galaxy clusters look “fluffy,” giving off a very diffuse signal in the X-ray band, unlike brighter, point-like sources, which have been interpreted as extremely active quasars or black holes.


“The images are either all points, or fluffs, and the fluffs are these giant million-light-year balls of hot gas that we call clusters, and the points are black holes that are accreting gas and glowing as this gas spirals in,” McDonald says. “This idea that you could have a rapidly accreting black hole at the center of a cluster — we didn’t think that was something that happened in nature.”


But the Phoenix discovery proved that galaxy clusters could indeed host immensely active black holes, prompting McDonald to wonder: Could there be other nearby galaxy clusters that were simply misidentified?

An extreme eater


To answer that question, the researchers set up a survey named CHiPS, for Clusters Hiding in Plain Sight, which is designed to reevaluate X-ray images taken in the past.


“We start from archival data of point sources, or objects that were super bright in the sky,” Somboonpanyakul explains. “We are looking for point sources inside fluffy things.”


For every point source that was previously identified, the researchers noted their coordinates and then studied them more directly using the Magellan Telescope, a powerful optical telescope that sits in the mountains of Chile. If they observed a higher-than-expected number of galaxies surrounding the point source (a sign that the gas may stem from a cluster of galaxies), the researchers looked at the source again, using NASA’s space-based Chandra X-Ray Observatory, to identify an extended, diffuse source around the main point source.


“Some 90 percent of these sources turned out to not be clusters,” McDonald says. “But the fun thing is, the small number of things we are finding are sort of rule-breakers.”


The new paper reports the first results of the CHiPS survey, which has so far confirmed one new galaxy cluster hosting an extremely active central black hole.


“The brightness of the black hole might be related to how much it’s eating,” McDonald says. “This is thousands of times brighter than a typical black hole at the center of a cluster, so it’s very extreme in its feeding. We have no idea how long this has been going on or will continue to go on. Finding more of these things will help us understand, is this an important process, or just a weird thing that there’s only one of in the universe.”


The team plans to comb through more X-ray data in search of galaxy clusters that might have been missed the first time around.


“If the CHiPS survey can find enough of these, we will be able to pinpoint the specific rate of accretion onto the black hole where it switches from generating primarily radiation to generating mechanical energy, the two primary forms of energy output from black holes,” says Brian McNamara, professor of physics and astronomy at the University of Waterloo, who was not involved in the research. “This particular object is interesting because it bucks the trend. Either the central supermassive black hole’s mass is much lower than expected, or the structure of the accretion flow is abnormal. The oddballs are the ones that teach us the most.”


In addition to shedding light on a black hole’s feeding, or accretion behavior, the detection of more galaxy clusters may help to estimate how fast the universe is expanding.


“Take for instance, the Titanic,” McDonald says. “If you know where the two biggest pieces landed, you could map them backward to see where the ship hit the iceberg. In the same way, if you know where all the galaxy clusters are in the universe, which are the biggest pieces in the universe, and how big they are, and you have some information about what the universe looked like in the beginning, which we know from the Big Bang, then you could map out how the universe expanded.”


This research was supported, in part, by the Kavli Research Investment Fund at MIT, and by NASA.


Jennifer Chu | MIT News Office


Source: Mit/News



Archive link


The Abyss of Time

image

Scotland is part of the bedrock of geology, so to speak.


In the late 18th century, Scottish farmer and scientist

James Hutton helped found the science of geology. Observing how wind and water

weathered rocks and deposited layers of soil at his farm in Berwickshire,

Hutton made a conceptual leap into a deeper and expansive view of time. After

spending decades observing the processes of erosion and sedimentation, and traveling

the Scottish countryside in search of fossils, stream cuts and interesting rock

formations, Hutton became convinced that Earth had to be much older than 6,000

years, the common belief in Western civilization at the time.


In 1788, a boat trip to Siccar Point, a rocky promontory in

Berwickshire, helped crystallize Hutton’s view. The Operational

Land Imager
 (OLI) on Landsat 8 acquired

this image of the area on June 4, 2018, top. A closer view of Siccar Point is

below.


image

At Siccar Point, Hutton was confronted with the

juxtaposition of two starkly different types of rock—a gently sloping bed of

young red sandstone that was over a near vertical slab of older graywacke that

had clearly undergone intensive heating, uplift, buckling, and folding. Hutton

argued to his two companions on the boat that the only way to get the two rock

formations jammed up against one another at such an odd angle was that an

enormous amount of time must have elapsed between when they had been deposited

at the bottom of the ocean.


He was right.


Read more: https://go.nasa.gov/2OBnyJ8




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


Pen-Y-Maen Standing Stone, Llandegfan, Anglesey, North Wales,…





Pen-Y-Maen Standing Stone, Llandegfan, Anglesey, North Wales, 14.8.18.


A solitary standing stone that may have a connection to the other solitary stone, Ty-Gwyn, only a few fields away. It is likely they indicated some prehistoric route from the coast inland.


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Unexpected Future Boost of Methane Possible from Arctic Permafrost


NASA – Arctic-Boreal Vulnerability Experiment (ABoVE) patch.


Aug. 17, 2018


New NASA-funded research has discovered that Arctic permafrost’s expected gradual thawing and the associated release of greenhouse gases to the atmosphere may actually be sped up by instances of a relatively little known process called abrupt thawing. Abrupt thawing takes place under a certain type of Arctic lake, known as a thermokarst lake that forms as permafrost thaws.



New Arctic Lakes Could Soon Be a Major Source of Atmospheric Methane

Video above: For centuries, a massive store of carbon has been locked underground in the Arctic’s permanently frozen soil known as permafrost. As Earth’s climate continues to warm, that carbon has begun to leach into the atmosphere, the result of microbes waking up and digesting once-frozen organic materials. Video Credits: NASA’s Goddard Space Flight Center/Katy Mersmann.


The impact on the climate may mean an influx of permafrost-derived methane into the atmosphere in the mid-21st century, which is not currently accounted for in climate projections.


The Arctic landscape stores one of the largest natural reservoirs of organic carbon in the world in its frozen soils. But once thawed, soil microbes in the permafrost can turn that carbon into the greenhouse gases carbon dioxide and methane, which then enter into the atmosphere and contribute to climate warming.


“The mechanism of abrupt thaw and thermokarst lake formation matters a lot for the permafrost-carbon feedback this century,” said first author Katey Walter Anthony at the University of Alaska, Fairbanks, who led the project that was part of NASA’s Arctic-Boreal Vulnerability Experiment (ABoVE), a ten-year program to understand climate change effects on the Arctic. “We don’t have to wait 200 or 300 years to get these large releases of permafrost carbon. Within my lifetime, my children’s lifetime, it should be ramping up. It’s already happening but it’s not happening at a really fast rate right now, but within a few decades, it should peak.”


The results were published in Nature Communications.


Using a combination of computer models and field measurements, Walter Anthony and an international team of U.S. and German researchers found that abrupt thawing more than doubles previous estimates of permafrost-derived greenhouse warming. They found that the abrupt thaw process increases the release of ancient carbon stored in the soil 125 to 190 percent compared to gradual thawing alone. What’s more, they found that in future warming scenarios defined by the Intergovernmental Panel on Climate Change, abrupt thawing was as important under the moderate reduction of emissions scenario as it was under the extreme business-as-usual scenario. This means that even in the scenario where humans reduced their global carbon emissions, large methane releases from abrupt thawing are still likely to occur.



Animation above: Arctic Lakes Could Soon Be a Major Source of Atmospheric Methane. Animation Credits: NASA’s Goddard Space Flight Center.


Permafrost is ground that is frozen year-round. In the Arctic, ice-rich permafrost soils can be up to 260 feet (80 meters) thick. Due to human-caused warming of the atmosphere from greenhouse gas emissions, a gradual thawing of the permafrost is currently taking place where the upper layer of seasonally thawed soil is gradually getting thicker and reaching deeper into the ground. This process wakes up microbes in the soil that decompose soil organic matter and as a result release carbon dioxide and methane back into the atmosphere. This gradual thaw process is accounted for in climate models and is thought to have minimal effect as thawed ground also stimulates the growth of plants, which counterbalance the carbon released into the atmosphere by consuming it during photosynthesis.


However, in the presence of thermokarst lakes, permafrost thaws deeper and more quickly. Thermokarst lakes form when substantial amounts of ice in the deep soil melts to liquid water. Because the same amount of ice takes up more volume than water, the land surface slumps and subsides, creating a small depression that then fills with water from rain, snow melt and ground ice melt. The water in the lakes speeds up the thawing of the frozen soil along their shores and expands the lake size and depth at a much faster pace than gradual thawing.


“Within decades you can get very deep thaw-holes, meters to tens of meters of vertical thaw,” Walter Anthony said. “So you’re flash thawing the permafrost under these lakes. And we have very easily measured ancient greenhouse gases coming out.”


These ancient greenhouse gases, produced from microbes chewing through ancient carbon stored in the soil, range from 2,000 to 43,000 years old. Walter Anthony and her colleagues captured methane bubbling out of 72 locations in 11 thermokarst lakes in Alaska and Siberia to measure the amount of gas released from the permafrost below the lakes, as well as used radiocarbon dating on captured samples to determine their age. They compared the emissions from lakes to five locations where gradual thawing occurs. In addition, they used the field measurements to evaluate how well their model simulated the natural field conditions.



Image above: Methane bubbles up from the thawed permafrost at the bottom of the thermokarst lake through the ice at its surface. Image Credits: Katey Walter Anthony/ University of Alaska Fairbanks.


Team members with the Alfred Wegener Institute (AWI) for Polar and Marine Research in Germany then used U.S. Geological Survey-NASA Landsat satellite imagery from 1999 to 2014 to determine the speed of lake expansion across a large region of Alaska. From this data they were able to estimate the amount of permafrost converted to thawed soil in lake bottoms.



U.S. Geological Survey-NASA Landsat satellite. Image Credits: USGS/NASA



“While lake change has been studied for many regions, the understanding that lake loss and lake gain have a very different outcome for carbon fluxes is new,” said co-author Guido Grosse of AWI. “Over a few decades, thermokarst lake growth releases substantially more carbon than lake loss can lock in permafrost again [when the lake bottoms refreeze].”


Because the thermokarst lakes are relatively small and scattered throughout the Arctic landscapes, computer models of their behavior are not currently incorporated into global climate models. However, Walter Anthony believes including them in future models is important for understanding the role of permafrost in the global carbon budget. Human fossil fuel emissions are the number one source of greenhouse gases to the atmosphere, and in comparison, methane emissions from thawing permafrost make up only one percent of the global methane budget, Walter Anthony said. “But by the middle to end of the century the permafrost-carbon feedback should be about equivalent to the second strongest anthropogenic source of greenhouse gases, which is land use change,” she said.


To learn more about ABoVE, visit: https://above.nasa.gov/


Earth Research Findings: https://www.nasa.gov/subject/7782/earth-research-findings


Landsat: http://www.nasa.gov/mission_pages/landsat/main/index.html


Climate: https://www.nasa.gov/subject/3127/climate


Images (mentioned), Animation (mentioned), Video (mentioned), Text, Credits: NASA/Sara Blumberg/Earth Science News Team, by Ellen Gray.


Greetings, Orbiter.chArchive link


Meteor Activity Outlook for August 11-17, 2018

Meteor near San Diego, CA – © slworking2, August 13th, 2017
Canon EOS 6D, 15mm, ƒ/2.8, 15s, ISO3200)

During this period the moon will reach its new phase on Saturday August 11th. At that time the moon will lie near the sun in the sky and will be invisible at night. As the week progresses the waxing crescent moon will enter the evening sky but will not cause much interference for meteor observers, especially during the more active morning hours. The estimated total hourly meteor rates for evening observers this week is near 7 as seen from mid-northern latitudes and also 5 for those viewing from subtropical southern latitudes (25S). For morning observers the estimated total hourly rates should be near 60 for those viewing from mid-northern latitudes and also 30 for those viewing from subtropical southern latitudes (25S). The actual rates will also depend on factors such as personal light and motion perception, local weather conditions, alertness and experience in watching meteor activity. Note that the hourly rates listed below are estimates as viewed from dark sky sites away from urban light sources. Observers viewing from urban areas will see less activity as only the brighter meteors will be visible from such locations.


The radiant (the area of the sky where meteors appear to shoot from) positions and rates listed below are exact for Saturday night/Sunday morning August 11/12. These positions do not change greatly day to day so the listed coordinates may be used during this entire period. Most star atlases (available at science stores and planetariums) will provide maps with grid lines of the celestial coordinates so that you may find out exactly where these positions are located in the sky. A planisphere or computer planetarium program is also useful in showing the sky at any time of night on any date of the year. Activity from each radiant is best seen when it is positioned highest in the sky, either due north or south along the meridian, depending on your latitude. It must be remembered that meteor activity is rarely seen at the radiant position. Rather they shoot outwards from the radiant so it is best to center your field of view so that the radiant lies near the edge and not the center. Viewing there will allow you to easily trace the path of each meteor back to the radiant (if it is a shower member) or in another direction if it is a sporadic. Meteor activity is not seen from radiants that are located far below the horizon. The positions below are listed in a west to east manner in order of right ascension (celestial longitude). The positions listed first are located further west therefore are accessible earlier in the night while those listed further down the list rise later in the night.





Radiant Positions at 22:00 LDT


Radiant Positions at 22:00

Local Daylight Saving Time






Radiant Positions at 01:00 LDT


Radiant Positions at 0100

Local Daylight Saving Time






Radiant Positions at 4:00 LDT


Radiant Positions at 04:00

Local Daylight Saving Time





These sources of meteoric activity are expected to be active this week.


The August Draconids (AUD) were discovered by Zdenek Sekanina in his study of meteor streams using radio methods. This stream is active from August 13-19 with maximum activity occurring on the 16th. The radiant is currently located at 18:04 (271) +59, which places it in southern Draco, 8 degrees north of the 2nd magnitude star known as Eltanin (gamma Draconis). This radiant is best placed near 2200 (10pm) local daylight saving time (LDT), when it lies on the meridian and is located highest in the sky. With an entry velocity of 21 km/sec., the average August Draconid meteor would be of slow velocity. Rates this week are expected to be less than 1 per hour no matter your location


The kappa Cygnids (KCG) should be active from a radiant located near 18:59 (285) +50. This area of the sky lies in southern Draco, 4 degrees southwest of the 4th magnitude star known as kappa Cygni. This radiant is best placed near 2300 (11pm) LDT, when it lies on the meridian and is located highest in the sky. Rates should be near 1 per hour as seen from mid-northern latitudes. Unfortunately these meteors are not well seen from the southern hemisphere due to their low radiant altitude. With an entry velocity of 21 km/sec., the average meteor from this source would be of slow velocity.


The center of the large Anthelion (ANT) radiant is currently located at 22:08 (332) -12. This position lies in western Aquarius, 2 degrees north of the 4th magnitude star known as iota Aquarii. Due to the large size of this radiant, Anthelion activity may also appear from eastern Capricornus as well as Aquarius. This radiant is best placed near 0200 LDT, when it lies on the meridian and is located highest in the sky. Hourly rates at this time should be near 2 as seen from mid-northern latitudes and 3 as seen from tropical southern latitudes. With an entry velocity of 30 km/sec., the average Anthelion meteor would be of medium-slow velocity.


The Northern delta Aquariids (NDA) are active from July 23 through August 27. The radiant is currently located at 23:04 (346) +02. This position is located in western Pisces, 3 degrees west of the 4th magnitude star known as gamma Piscium. Maximum activity is on August 14, so hourly rates should be near 1 per hour no matter your location. The radiant is best placed near 0300 LDT, when it lies highest in the sky. With an entry velocity of 38 km/sec., these meteors would be of medium velocities. This shower seems to be a continuation of the Northern June Aquilids, which had been active since early June.


The Southern Delta Aquariids (SDA) are active from a radiant located at 23:30 (353) -12. This position is located in eastern Aquarius directly between the faint stars known as psi and omega Aquarii. Hourly rates are now only 1 per hour as seen from the  northern hemisphere and 2 per hour for those south of the equator. The radiant is best placed near 0400 LDT, when it lies highest in the sky. With an entry velocity of 41 km/sec., most activity from this radiant would be of average velocities.


The Piscids Austrinids (PAU) are an obscure shower, not well seen from the northern hemisphere. Recent studies by the IMO Video Network shows no activity at all. Other studies have indicated that this shower is active later than previously thought. We will go along with that idea until more information is available. It is now thought that this radiant is active from July 30 through August 18, with maximum activity occurring on the 8th. Using these parameters, the current position of the radiant would be 23:44 (356) -19. This area of the sky is located in southern Aquarius, near the faint stars known as 106 and 107 Aquarii. The radiant is best placed near 0400 LDT, when it lies highest in the sky. Current rates would most likely be less than 1 per hour, no matter your location. With an entry velocity of 44km/sec., most activity from this radiant would be of average velocities.


The beta Hydrusids (HDY) are only known through an outburst reported on August 17, 1985. Activity from this stream is seen from August 15-19 with maximum activity occurring on the 17th. At maximum the radiant lies at 02:25 (036) -75, which places it in southern Hydrus between the bright stars known as beta and gamma Hydri. Due to the far southern location, these meteors are not visible from the northern hemisphere. For southern observers, this area of the sky is best seen during the last dark hour before dawn when the radiant lies highest in a dark sky. Current rates are expected to be less than 1 per hour during this period no matter your location. With an entry velocity of 23 km/sec., the average meteor from this source would be of slow velocity.


The eta Eridanids (ERI) were discovered by Japanese observers back in 2001. Activity from this stream is seen from July 23 though September 17 with maximum activity occurring on August 11. The radiant currently lies at 03:00 (045) -12, which places it in western Eridanus, 2 degrees southeast of the 4th magnitude star known as Azha (eta Eridani). This area of the sky is best seen during the last dark hour before dawn when the radiant lies highest in a dark sky. Current rates are expected to near 1 per hour as seen from the northern hemisphere and near 2 per hour as seen from south of the equator. With an entry velocity of 65 km/sec., the average meteor from this source would be of swift velocity.


The Perseids (PER) reach maximum activity on August 12/13 from a radiant located at 03:12 (048) +57. This position lies in northern Perseus, 3 degrees northeast of the 3rd magnitude star known as gamma Persei. This area of the sky is best placed for viewing during the last dark hour before dawn when it lies highest in the sky. Rates from dark sky sites are expected to be near 60 per hour as seen from the northern hemisphere and 20 as seen from south of the equator. Unfortunately these meteors are not well seen from the southern hemisphere as the numbers decrease to zero from mid-southern latitudes (S45). With an entry velocity of 59 km/sec., the average meteor from this source would be of swift velocity.


As seen from the mid-northern hemisphere (45N) one would expect to see approximately 14 sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near 4 per hour. As seen from the tropical southern latitudes (25S), morning rates would be near 10 per hour as seen from rural observing sites and 3 per hour during the evening hours. Locations between these two extremes would see activity between the listed figures.


The list below offers the information from above in tabular form. Rates and positions are exact for Saturday night/Sunday morning except where noted in the shower descriptions.








































































































SHOWER DATE OF MAXIMUM ACTIVITY CELESTIAL POSITION ENTRY VELOCITY CULMINATION HOURLY RATE CLASS
RA (RA in Deg.) DEC Km/Sec Local Daylight Saving Time North-South
August Draconids (AUD) Aug 16 18:04 (271) +59 21 22:00 <1 – <1 II
kappa Cygnids (KCG) Aug 13 18:59 (285) +50 21 23:00 1 – <1 II
Anthelions (ANT) 22:08 (332) -12 30 02:00 2 – 3 III
Northern delta Aquariids (NDA) Aug 14 23:04 (346) +02 38 03:00 1 – 1 IV
Southern delta Aquariids (SDA) Jul 30 23:30 (353) -12 41 04:00 1 – 2 I
Piscids Austrinids (PAU) Aug 08 23:44 (356) -19 44 04:00 <1 – <1 IV
beta Hydrusids (HDY) Aug 17 02:25 (036) -75 23 06:00 0 – <1 III
eta Eridanids (ERI) Aug 11 03:00 (045) -12 65 07:00 1 – 2 IV
Perseids (PER) Aug 13 03:12 (048) +57 59 07:00 40 – 15 I

‘Eslie The Greater’ Stone Circle, nr. Banchory,…









‘Eslie The Greater’ Stone Circle, nr. Banchory, Scotland, 16.8.18.


A second visit to this large semi-ruinous recumbent stone circle and central cairn.


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