пятница, 15 марта 2019 г.

Physicists reverse time using quantum computer

Researchers from the Moscow Institute of Physics and Technology teamed up with colleagues from the U.S. and Switzerland and returned the state of a quantum computer a fraction of a second into the past. They also calculated the probability that an electron in empty interstellar space will spontaneously travel back into its recent past.

Physicists reverse time using quantum computer
Time reversal [Credit: @tsarcyanide/MIPT]

“This is one in a series of papers on the possibility of violating the second law of thermodynamics. That law is closely related to the notion of the arrow of time that posits the one-way direction of time: from the past to the future,” commented the study’s lead author Gordey Lesovik, who heads the Laboratory of the Physics of Quantum Information Technology at MIPT.

“We began by describing a so-called local perpetual motion machine of the second kind. Then, in December, we published a paper that discusses the violation of the second law via a device called a Maxwell’s demon,” Lesovik said. “The most recent paper approaches the same problem from a third angle: We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time.”

What makes the future different from the past

Most laws of physics make no distinction between the future and the past. For example, let an equation describe the collision and rebound of two identical billiard balls. If a close-up of that event is recorded with a camera and played in reverse, it can still be represented by the same equation. Moreover, one could not tell from the recording if it has been doctored. Both versions look plausible. It would appear that the billiard balls defy the intuitive sense of time.

However, imagine that someone has recorded a cue ball breaking the pyramid, the billiard balls scattering in all directions. One need not know the rules of the game to tell the real-life scenario from reverse playback. What makes the latter look so absurd is our intuitive understanding of the second law of thermodynamics: An isolated system either remains static or evolves toward a state of chaos rather than order.

Most other laws of physics do not prevent rolling billiard balls from assembling into a pyramid, infused tea from flowing back into the tea bag, or a volcano from “erupting” in reverse. But we do not see any of this happening, because that would require an isolated system to assume a more ordered state without any outside intervention, which runs contrary to the second law. The nature of that law has not been explained in full detail, but researchers have made great headway in understanding the basic principles behind it.

Spontaneous time reversal

Quantum physicists from MIPT decided to check if time could spontaneously reverse itself at least for an individual particle and for a tiny fraction of a second. That is, instead of colliding billiard balls, they examined a solitary electron in empty interstellar space.

“Suppose the electron is localized when we begin observing it. This means that we’re pretty sure about its position in space. The laws of quantum mechanics prevent us from knowing it with absolute precision, but we can outline a small region where the electron is localized,” says study co-author Andrey Lebedev from MIPT and ETH Zurich.

The physicist explains that the evolution of the electron state is governed by Schrödinger’s equation. Although it makes no distinction between the future and the past, the region of space containing the electron will spread out very quickly. That is, the system tends to become more chaotic. The uncertainty of the electron’s position is growing. This is analogous to the increasing disorder in a large-scale system — such as a billiard table — due to the second law of thermodynamics.

Physicists reverse time using quantum computer
The four stages of the actual experiment on a quantum computer mirror the stages of the thought experiment
involving an electron in space and the imaginary analogy with billiard balls. Each of the three systems initially
evolves from order toward chaos, but then a perfectly timed external disturbance reverses this process
[Credit: @tsarcyanide/MIPT]

“However, Schrödinger’s equation is reversible,” adds Valerii Vinokur, a co-author of the paper, from the Argonne National Laboratory, U.S. “Mathematically, it means that under a certain transformation, called complex conjugation, the equation will describe a ‘smeared’ electron localizing back into a small region of space over the same time period.” Although this phenomenon is not observed in nature, it could theoretically happen due to a random fluctuation in the cosmic microwave background permeating the universe.
The team set out to calculate the probability to observe an electron “smeared out” over a fraction of a second spontaneously localizing into its recent past. It turned out that even if one spent the entire lifetime of the universe — 13.7 billion years — observing 10 billion freshly localized electrons every second, the reverse evolution of the particle’s state would only happen once. And even then, the electron would travel no more than a mere one ten-billionth of a second into the past.

Large-scale phenomena involving billiard balls, volcanoes, etc. obviously unfold on much greater timescales and feature an astounding number of electrons and other particles. This explains why we do not observe old people growing younger or an ink blot separating from the paper.

Reversing time on demand

The researchers then attempted to reverse time in a four-stage experiment. Instead of an electron, they observed the state of a quantum computer made of two and later three basic elements called superconducting qubits.

Stage 1: Order. Each qubit is initialized in the ground state, denoted as zero. This highly ordered configuration corresponds to an electron localized in a small region, or a rack of billiard balls before the break.

Stage 2: Degradation. The order is lost. Just like the electron is smeared out over an increasingly large region of space, or the rack is broken on the pool table, the state of the qubits becomes an ever more complex changing pattern of zeros and ones. This is achieved by briefly launching the evolution program on the quantum computer. Actually, a similar degradation would occur by itself due to interactions with the environment. However, the controlled program of autonomous evolution will enable the last stage of the experiment.

Stage 3: Time reversal. A special program modifies the state of the quantum computer in such a way that it would then evolve “backwards,” from chaos toward order. This operation is akin to the random microwave background fluctuation in the case of the electron, but this time it is deliberately induced. An obviously far-fetched analogy for the billiards example would be someone giving the table a perfectly calculated kick.

Stage 4: Regeneration. The evolution program from the second stage is launched again. Provided that the “kick” has been delivered successfully, the program does not result in more chaos but rather rewinds the state of the qubits back into the past, the way a smeared electron would be localized or the billiard balls would retrace their trajectories in reverse playback, eventually forming a triangle.

The researchers found that in 85 percent of the cases the two-qubit quantum computer indeed returned back into the initial state. When three qubits were involved, more errors happened, resulting in a roughly 50 percent success rate. According to the authors, these errors are due to imperfections in the actual quantum computer. As more sophisticated devices are designed, the error rate is expected to drop.

Interestingly, the time reversal algorithm itself could prove useful for making quantum computers more precise. “Our algorithm could be updated and used to test programs written for quantum computers and eliminate noise and errors,” Lebedev explained.

The study is published in Scientific Reports.

Source: Moscow Institute of Physics and Technology [March 13, 2019]



Climate change could devastate painted turtles, according to new study

An Iowa State University biologist is sounding the alarm for the painted turtle, one of many reptiles for which climate change could prove particularly threatening.

Climate change could devastate painted turtles, according to new study
Climate change threatens the painted turtle, a species that undergoes temperature-dependent sex determination.
Research led by Nicole Valenzuela indicates that warming temperatures, as well as wider fluctuations
 in temperature, could lead to a demographic collapse of the painted turtle
[Credit: Nicole Valenzuela]

Fluctuations in temperature driven by climate change could devastate a range of species for which sex is determined by temperature during critical stages of development, according to recently published research led by Nicole Valenzuela, a professor of ecology, evolution and organismal biology. Rising temperatures, along with wider oscillations in temperature, could disrupt the ratio of males to females in painted turtle populations and threaten the survival of the species, Valenzuela said. The research was published this week in the peer-reviewed journal Scientific Reports.

Painted turtles undergo temperature-dependent sex determination while developing inside the egg. Eggs exposed to warmer temperatures tend to produce females, while cooler temperatures tend to produce males, Valenzuela said. Numerous turtle species – as well as crocodilians, some lizards and the tuatara – undergo temperature-dependent sex determination. And increasing average temperatures combined with stronger thermal fluctuations that result from climate change could lead to drastic shifts in the demographics of those species, she said, eventually leading to population collapse and possibly extinction.

Valenzuela and her coauthors exposed eggs from Iowa to temperatures recorded in nests from three different painted turtle populations in Iowa, Nebraska and Canada from which the proportion of males and females was also recorded. Valenzuela said that allowed the experiments to compare the responses of multiple painted turtle populations, which revealed that not all populations exhibit the same sensitivity to temperature.

Valenzuela’s previous studies exposed turtle eggs to constant temperatures in a laboratory to gauge the impact on sex determination, finding that an increase of about 4 degrees Celsius can mean the difference between a nest that produces only males and a nest that produces only females. But those experiments failed to account for the fluctuations nests encounter in the wild. Follow up studies with the simplest possible fluctuations (cycles of 12 hours 5 degrees Celsius above and 12 hours of 5 degrees Celsius below those constant values) caused sex reversal, or the process of some eggs producing males despite warmer average temperatures. Valenzuela hoped that if similar fluctuations caused sex reversal in natural nests, it could counter the effect of warmer temperature averages, alleviating the effects of climate change.

Valenzuela’s most recent experiments found this not to be the case, however. In a lab experiment that exposed eggs to temperature fluctuations mimicking conditions found in nature, and to conditions in which the oscillations were exaggerated to mimic climate change scenarios, the researchers discovered the trend still points toward nests producing a high proportion of females. The research showed that cooler temperature profiles that would tend to produce males trended toward females when the temperature fluctuations intensified. Embryos from warmer profiles, on the other hand, remained female or died when the fluctuations intensified.

“If what we found is generalizable to other species with temperature-dependent sex determination, this is bad news,” she said. “If an average increase in temperature is accompanied by greater variance, we’ll see populations becoming unisexual faster than anticipated. The greater oscillations add to the effect of just higher average temperature.”

Valenzuela said loss of habitat and exploitation has already left many turtles vulnerable to extinction, and climate change only adds to the peril these species face.

“The whole message here is the potential effects climate change can have on these species and the importance of our findings for conservation,” she said. “Turtles are the most vulnerable group of vertebrates, and many use temperature-dependent sex determination.”

Source: Iowa State University [March 13, 2019]



Measuring the success of East African protected areas

East Africa (Burundi, Kenya, Rwanda, Tanzania and Uganda) contains 1,776 protected areas (including 186 “strict” protected areas) covering more than 27 percent of its terrestrial area. Researchers at UC Davis have now documented the extent to which this East African protected area network really protects wildlife and habitats.

Measuring the success of East African protected areas
Sunset over Kitulo National Park in Tanzania, one of the first East African protected areas to be primarily
established for the conservation of rare plants [Credit: Jason Riggio]

According to their publication in the open-access journal Global Ecology and Conservation, 86% of ecoregions in East Africa have achieved the Convention on Biological Diversity’s Aichi Target 11 goal of protecting at least 10 percent of each ecoregion by 2020. However, three ecoregions (two in the deserts of northern Kenya and the coastal forests of southeastern Tanzania) are poorly represented with less than 10 percent of their area under some form of protection.
“While a 10 percent protection target may be an arbitrarily low bar, it does show that countries have made substantial progress in achieving the targets set by the international community,” said lead author Jason Riggio, a UC Davis postdoctoral scholar in the Department of Wildlife, Fish and Conservation Biology.

Using the same target for the protection of endemic and near-endemic species (those that have at least 90 percent of their entire distribution contained within East Africa), the researchers found that protected areas cover at least 10 percent of the distribution of 256 of 303 East African endemics. However, many (37 percent) of these species’ ranges do not have 10 percent coverage by strict protected areas.

Measuring the success of East African protected areas
East Africa (Burundi, Kenya, Rwanda, Tanzania and Uganda) contains 1,776 protected areas
(including 186 “strict” protected areas) covering more than 27 percent of its terrestrial area.
Researchers at UC Davis have now documented the extent to which this East African protected
area network really protects wildlife and habitats [Credit: Jason Riggio, UC Davis]

“We use the protection of endemic species in the region as indicators of representativeness as these species necessarily have small ranges and their conservation outlook is primarily driven by conservation decisions made at local and regional levels,” said Tim Caro, co-author on the paper and a professor in the UC Davis Department of Wildlife, Fish and Conservation Biology.

Using a land conversion map based on high spatial resolution satellite images, the scientists assessed encroachment on East African protected areas by agriculture and other land uses. Encouragingly, they found that only 6.8 percent of all protected areas, and just 1.6 percent of strict protected areas, has been converted to agriculture or other human use.

“Our results provide very strong evidence that strict protection has been successful in safeguarding habitat,” said Andrew Jacobson, co-author and incoming professor at the Center for the Environment at Catawba College in North Carolina.

Their analyses indicate that the East African network of protected areas is extensive in both number and area, that it protects most natural habitats effectively, and that further expansion of protected areas to cover some priority biodiversity conservation areas is still possible and necessary. The paper recommends focusing on increasing representation in northern Kenya, in coastal forests in southeastern Tanzania, and on targeted reserves in Central and Western Uganda.

Author: Jason Riggio  Source: UC Davis [March 13, 2019]



Unique diversity of the genetic history of the Iberian Peninsula revealed

An international team of researchers have analyzed ancient DNA from almost 300 individuals from the Iberian Peninsula, spanning more than 12,000 years, in two studies published in Current Biology and Science. The first study looked at hunter-gatherers and early farmers living in Iberia between 13,000 and 6000 years ago. The second looked at individuals from the region during all time periods over the last 8000 years. Together, the two papers greatly increase our knowledge about the population history of this unique region.

Unique diversity of the genetic history of the Iberian Peninsula revealed
A man and woman buried side by side at the Bronze Age site of Castillejo de Bonete in Spain had different
 genetic ancestries [Credit: Luis Benítez de Lugo Enrich and José Luis Fuentes Sánchez/Oppida]

The Iberian Peninsula has long been thought of as an outlier in the population history of Europe, due to its unique climate and position on the far western edge of the continent. During the last Ice Age, Iberia remained relatively warm, allowing plants and animals – and possibly people – who were forced to retreat from much of the rest of Europe to continue living there.
Similarly, over the last 8000 years, Iberia’s geographic location, rugged terrain, position on the Mediterranean coast and proximity to North Africa made it unique in comparison to other parts of Europe in its interactions with other regions. Two new studies, analyze a total of almost 300 individuals who lived from about 13,000 to 400 years ago to give unprecedented clarity on the unique population history of the Iberian Peninsula.

Iberian hunter-gatherers show two ancient Palaeolithic lineages

For the paper in Current Biology, led by researchers at the Max Planck Institute for the Science of Human History, researchers analyzed 11 hunter-gatherers and Neolithic individuals from Iberia. The oldest newly analyzed individuals are approximately 12,000 years old and were recovered from Balma Guilanyà in Spain.

Unique diversity of the genetic history of the Iberian Peninsula revealed
Excavation work in progress at the site of Balma Guilanyà [Credit: CEPAP-UAB]

Earlier evidence had shown that, after the end of the last Ice Age, western and central Europe were dominated by hunter-gatherers with ancestry associated with an approximately 14,000-year-old individual from Villabruna, Italy. Italy is thought to have been a potential refuge for humans during the last Ice Age, like Iberia. The Villabruna-related ancestry largely replaced earlier ancestry in western and central Europe related to 19,000-15,000-year-old individuals associated with what is known as the Magdalenian cultural complex.
Interestingly, the findings of the current study show that both lineages were present in Iberian individuals dating back as far as 19,000 years ago. “We can confirm the survival of an additional Paleolithic lineage that dates back to the Late Ice Age in Iberia,” says Wolfgang Haak of the Max Planck Institute for the Science of Human History, senior author of the study. “This confirms the role of the Iberian Peninsula as a refuge during the Last Glacial Maximum, not only for fauna and flora but also for human populations.”

This suggests that, far from being replaced by Villabruna-related individuals after the last Ice Age, hunter-gatherers in Iberia in fact already had ancestry from Magdalenian- and Villabruna-related sources. The discovery suggests an early connection between two potential refugia, resulting in a genetic ancestry that survived in later Iberian hunter-gatherers.

Unique diversity of the genetic history of the Iberian Peninsula revealed
Cueva de Chaves site [Credit: Museo de Huesca]

“The hunter-gatherers from the Iberian Peninsula carry a mix of two older types of genetic ancestry: one that dates back to the Last Glacial Maximum and was once maximized in individuals attributed to Magdalenian culture and another one that is found everywhere in western and central Europe and had replaced the Magdalenian lineage during the Early Holocene everywhere except the Iberian Peninsula,” explains Vanessa Villalba-Mouco of the Max Planck Institute for the Science of Human History, first author of the study.

The researchers hope that ongoing efforts to decipher the genetic structure of late hunter-gatherer groups across Europe will help to even better understand Europe’s past and, in particular, the assimilation of a Neolithic way of life brought about by expanding farmers from the Near East during the Holocene.

Ancient DNA from individuals spanning the last 8000 years helps clarify the history and prehistory of the Iberian Peninsula

The paper published in Science focuses on slightly later time periods, and traces the population history of Iberia over the last 8000 years by analyzing ancient DNA from a huge number of individuals. The study, led by Harvard Medical School and the Broad Institute and including Haak and Villalba-Mouco, analyzed 271 ancient Iberians from the Mesolithic, Neolithic, Copper Age, Bronze Age, Iron Age and historical periods. The large number of individuals allowed the team to make more detailed inferences about each time period than previously possible.

The researchers found that during the transition to a sedentary farming life-style, hunter-gatherers in Iberia contributed subtly to the genetic make-up of newly arriving farmers from the Near East. “We can see that there must have been local mixture as the Iberian farmers also carry this dual signature of hunter-gatherer ancestry unique to Iberia,” explains Villalba-Mouco.

Unique diversity of the genetic history of the Iberian Peninsula revealed
La Braña 1 and 2 Mesolithic hunter-gatherers (Leon, Spain), found to be brothers
[Credit: Julio Manuel Vidal Encinas]

Between about 2500-2000 BC, the researchers observed the replacement of 40% of Iberia’s ancestry and nearly 100% of its Y-chromosomes by people with ancestry from the Pontic Steppe, a region in what is today Ukraine and Russia. Interestingly, the findings show that in the Iron Age, “Steppe ancestry” had spread not only into Indo-European-speaking regions of Iberia but also into non-Indo-European-speaking ones, such as the region inhabited by the Basque. The researchers’ analysis suggests that present-day Basques most closely resemble a typical Iberian Iron Age population, including the influx of “Steppe ancestry,” but that they were not affected by subsequent genetic contributions that affected the rest of Iberia. This suggests that Basque speakers were equally affected genetically as other groups by the arrival of Steppe populations, but retained their language in any case. It was only after that time that they became relatively isolated genetically from the rest of the Iberian Peninsula.
Additionally, the researchers looked at historical periods, including times when Greek and later Roman settlements existed in Iberia. The researchers found that beginning at least in the Roman period, the ancestry of the peninsula was transformed by gene flow from North Africa and the eastern Mediterranean. They found that Greek and Roman settlements tended to be quite multiethnic, with individuals from the central and eastern Mediterranean and North Africa as well as locals, and that these interactions had lasting demographic as well as cultural impacts.

“Beyond the specific insights about Iberia, this study serves as a model for how a high-resolution ancient DNA transect continuing into historical periods can be used to provide a detailed description of the formation of present-day populations,” explains Haak. “We hope that future use of similar strategies will provide equally valuable insights in other regions of the world.”

Source: Max Planck Institute for the Science of Human History [March 14, 2019]



Diet-induced changes favour innovation in speech sounds

Diet-induced changes in the human bite resulted in new sounds such as “f” in languages all over the world, a study by an international team led by researchers at the University of Zurich has shown. The findings contradict the theory that the range of human sounds has remained fixed throughout human history.

Diet-induced changes favour innovation in speech sounds
Milling grain meant less wear and tear on neolithic teeth, which had other effects on language
[Credit: Juan Aunion/Shutterstock.com]

Human speech is incredibly diverse, ranging from ubiquitous sounds like “m” and “a” to the rare click consonants in some languages of Southern Africa. This range of sounds is generally thought to have been established with the emergence of the Homo sapiens around 300,000 years ago.
A study by an international group headed up by scientists at the University of Zurich and involving researchers at two Max Planck Institutes, the University of Lyon and Nanyang Technological University Singapore now sheds new light on the evolution of spoken language. The study shows that sounds such as “f” and “v”, both common in many modern languages, are a relatively recent development that was brought about by diet-induced changes in the human bite.

Dental changes allow new sounds

While the teeth of humans used to meet in an edge-to-edge bite due to their harder and tougher diet at the time, more recent softer foods allowed modern humans to retain the juvenile overbite that had previously disappeared by adulthood, with the upper teeth slightly more in front than the lower teeth. This shift led to the rise of a new class of speech sounds now found in half of the world’s languages: labiodentals, or sounds made by touching the lower lip to the upper teeth, for example when pronouncing the letter “f”.

Diet-induced changes favour innovation in speech sounds
The difference between a Palaeolithic edge-to-edge bite (left) and a modern overbite/overjet bite (right)
[Credit: Tímea Bodogán]

“In Europe, our data suggests that the use of labiodentals has increased dramatically only in the last couple of millennia, correlated with the rise of food processing technology such as industrial milling,” explains Steven Moran, one of the two co-first authors of the study. “The influence of biological conditions on the development of sounds has so far been underestimated.”
Interdisciplinary approach to verify hypothesis

The project was inspired by an observation made by linguist Charles Hockett back in 1985. Hockett noticed that languages that foster labiodentals are often found in societies with access to softer foods. “But there are dozens of superficial correlations involving language which are spurious, and linguistic behavior, such as pronunciation, doesn’t fossilize,” says co-first author Damián Blasi.

Diet-induced changes favour innovation in speech sounds
Palaeolithic edge-to-edge bite (top) and a modern overbite/overjet bite (bottom) and how “f” sounds
are produced in a biomechanical model [Credit: Tímea Bodogán/Scott Moisik]

In order to unravel the mechanisms underlying the observed correlations, the scientists combined insights, data and methods from across the sciences, including biological anthropology, phonetics and historical linguistics. “It was a rare case of consilience across disciplines,” says Blasi. What made the project possible was the availability of newly developed, large datasets, detailed biomechanical simulation models, and computationally intensive methods of data analysis, according to the researchers.
Listening in on the past

“Our results shed light on complex causal links between cultural practices, human biology and language,” says Balthasar Bickel, project leader and UZH professor. “They also challenge the common assumption that, when it comes to language, the past sounds just like the present.” Based on the findings of the study and the new methods it developed, linguists can now tackle a host of unsolved questions, such as how languages actually sounded thousands of years ago. Did Caesar say “veni, vidi, vici” – or was it more like “weni, widi, wici'”?

The findings are published in Science.

Source: University of Zurich [March 14, 2019]



New study finds evidence of Neanderthal cannibalism and mobile modern humans driving...

A new international study indicates that Neanderthals and early modern humans probably had very similar diets, contradicting the assumption that Neanderthals died out because their diet was insufficiently varied. But modern humans may have had an advantage because they were more mobile and had better connections over longer distances, according to a team headed by Dr. Christoph Wißing at the University of Tübingen.

New study finds evidence of Neanderthal cannibalism and mobile modern humans driving mammoths to extinction
Bones from Spy offer clues to the diet and mobility of Neanderthals who lived there
[Credit: Royal Belgian Institute of Natural Sciences. Credit: RBINS]

Together with colleagues from the Senckenberg Centre for Human Evolution and Palaeoenvironment (HEP) in Tübingen, Belgium, France, Spain, Japan and the USA, he compared isotope data from fossil bones of the last Neanderthals, early modern humans and animals, drawing new conclusions about the nutrition and migration of human species investigated and the ecosystems of the time.

In the Late Pleistocene there were two different species of humans in Europe: the Neanderthals and our early modern human ancestors. They coexisted for several thousand years. In the study, the scientists compared stable isotope data from the sites of the Troisième caverne of Goyet, Spy and Scladina in Belgium as well as Lommersum in Germany. Goyet is the only burial site in Europe where the remains of both the last Neanderthals and of early modern humans have been found. “It gives us the chance to reconstruct and compare the ecology of both types of humans,” says Christoph Wißing.

The team found that the two species had similar diets, each hunting large mammals such as mammoths and woolly rhinoceros. But it appears to have been the arrival of modern humans which increased the pressure on the slow-breeding mammoth population.

Isotopic analysis suggested the individual mobility history of the modern humans differed considerably within a group. The authors hypothesize that more variable, broader and probably stronger transregional networks existed for modern humans, and that more intensive resource utilization and a more efficient exchange of ideas and possibly people were more typical for the early modern Europeans than for the Neanderthals at that time, who appear to have been less mobile.

The researchers found that the Neanderthals from Spy were “locals” who hunted most of their prey near the Belgian sites. But the Goyet Neanderthals obtained most of their prey outside of the local ecosystem and were therefore classified as non-local. What’s more, the bones of these Neanderthals display evidence of intensive cannibalism.

The majority of the Goyet Neanderthal bones bear traces of defleshing, disarticulation, and fracturing. This is in contrast with the “local” Neanderthals of Spy whose bones show no signs of butchering. It remains unclear where the Neanderthals from Goyet originally came from, whether they died at the cave, or if their bones were transported there.

The results of the study have been published in Scientific Reports.

Source: Universitaet Tübingen [March 14, 2019]



Expedition 59 Welcomes Three New Crew Members

ISS – Expedition 59 Mission patch.

March 15, 2019

NASA astronauts Nick Hague and Christina Koch, and cosmonaut Alexey Ovchinin of Roscosmos joined NASA astronaut Anne McClain, Expedition 59 commander Oleg Kononenko of Roscosmos, and David Saint-Jacques of the Canadian Space Agency aboard the International Space Station when the hatches between the Soyuz spacecraft and the orbiting laboratory officially opened at 11:07 p.m. EDT.

The trio’s arrival returns the orbiting laboratory’s population to six, including three NASA astronauts. McClain, Saint-Jacques and Kononenko are scheduled to remain aboard the station until June, while Hague, Koch and Ovchinin are set to return to Earth early this fall.

Image above: Expedition 59 crew members Anne McClain, Oleg Konoenko, and David Saint-Jacques welcome their new crew members, Nick Hague, Christina Koch, and Alexey Ovchinin, who arrived to the International Space Station on March 14, 2019. Image Credit: NASA TV.

McClain, Saint-Jacques, Hague and Koch also are all scheduled for the first spacewalks of their careers to continue upgrades to the orbital laboratory. McClain and Hague are scheduled to begin work to upgrade the power system March 22, and McClain and Koch will complete the upgrades to two station power channels during a March 29 spacewalk. This will be the first-ever spacewalk with all-female spacewalkers. Hague and Saint-Jacques will install hardware for a future science platform during an April 8 spacewalk.

Three resupply spacecraft – a Russian Progress, Northrop Grumman Cygnus and SpaceX Dragon – are scheduled to arrive with additional supplies for the crew and various science investigations. The crew also is scheduled to be onboard during test flights of NASA’s Commercial Crew Program, which will return human spaceflight launches for space station missions to U.S. soil.

Soyuz MS-12 hatch opening

For more than 18 years, humans have lived and worked continuously aboard the station, advancing scientific knowledge and demonstrating new technologies, making research breakthroughs not possible on Earth that will enable long-duration human and robotic exploration into deep space, including the Moon and Mars. A global endeavor, 236 people from 18 countries have visited the unique microgravity laboratory that has hosted more than 2,500 investigations from researchers in 106 countries. Investigations conducted on the International Space Station impact the daily lives of people on Earth and prepare the way for humans to venture farther into space.

Related articles:

Soyuz Docked to Space Station

Crew Safely in Orbit After Successful Launch

Related links:

Expedition 58: https://www.nasa.gov/mission_pages/station/expeditions/expedition58/index.html

Expedition 59: https://www.nasa.gov/mission_pages/station/expeditions/expedition59/index.html

NASA’s Commercial Crew Program: https://www.nasa.gov/exploration/commercial/crew/index.html

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), Video, Text, Credits: NASA/Norah Moran/NASA TV/SciNews.

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Cooking up Alien Atmospheres on Earth

Astrobiology & Exobilogy logo.

March 15, 2019

Researchers at NASA’s Jet Propulsion Laboratory in Pasadena, California, are cooking up an alien atmosphere right here on Earth. In a new study, JPL scientists used a high-temperature “oven” to heat a mixture of hydrogen and carbon monoxide to more than 2,000 degrees Fahrenheit (1,100 Celsius), about the temperature of molten lava. The aim was to simulate conditions that might be found in the atmospheres of a special class of exoplanets (planets outside our solar system) called “hot Jupiters.”

Image above: This artist’s concept shows planet KELT-9b, an example of a “hot Jupiter,” or a gas giant planet orbiting very close to its parent star. KELT-9b is an extreme example of a hot Jupiter, with dayside temperatures reaching 7,800 degrees Fahrenheit (4,300 Celcius). Image Credits: NASA/JPL-Caltech.

Hot Jupiters are gas giants that orbit very close to their parent star, unlike any of the planets in our solar system. While Earth takes 365 days to orbit the Sun, hot Jupiters orbit their stars in less than 10 days. Their close proximity to a star means their temperatures can range from 1,000 to 5,000 degrees Fahrenheit (530 to 2,800 degrees Celsius) or even hotter. By comparison, a hot day on the surface of Mercury (which takes 88 days to orbit the Sun) reaches about 800 degrees Fahrenheit (430 degrees Celsius).

“Though it is impossible to exactly simulate in the laboratory these harsh exoplanet environments, we can come very close,” said JPL principal scientist Murthy Gudipati, who leads the group that conducted the new study, published last month in the Astrophysical Journal.

The team started with a simple chemical mixture of mostly hydrogen gas and 0.3 percent carbon monoxide gas. These molecules are extremely common in the universe and in early solar systems, and they could reasonably compose the atmosphere of a hot Jupiter. Then the team heated the mixture to between 620 and 2,240 degrees Fahrenheit (330 and 1,230 Celsius).

Image above: JPL scientists used the “oven” (center) to heat a mixture of hydrogen and carbon monoxide and subject it to UV radiation, generated by a hydrogen gas discharge lamp. The lamp radiates both visible light (the pink glow) and UV light, which enters the gas container inside the oven via a window on the right side. Image Credits: NASA/JPL-Caltech.

The team also exposed the laboratory brew to a high dose of ultraviolet radiation – similar to what a hot Jupiter would experience orbiting so close to its parent star. The UV light proved to be a potent ingredient. It was largely responsible for some of the study’s more surprising results about the chemistry that might be taking place in these toasty atmospheres.

Hot Jupiters are large by planet standards, and they radiate more light than cooler planets. Such factors have allowed astronomers to gather more information about their atmospheres than most other types of exoplanets. Those observations reveal that many hot Jupiter atmospheres are opaque at high altitudes. Although clouds might explain the opacity, they become less and less sustainable as the pressure decreases, and the opacity has been observed where the atmospheric pressure is very low.

Scientists have been looking for potential explanations other than clouds, and aerosols – solid particles suspended in the atmosphere – could be one. However, according to the JPL researchers, scientists were previously unaware of how aerosols might develop in hot Jupiter atmospheres. In the new experiment, adding UV light to the hot chemical mix did the trick.

Image above: The small sapphire disk on the right shows organic aerosols formed inside a high-temperature oven. The disk to the left has not been used. Image Credits: NASA/JPL-Caltech.

“This result changes the way we interpret those hazy hot Jupiter atmospheres,” said Benjamin Fleury, a JPL research scientist and lead author of the study. “Going forward, we want to study the properties of these aerosols. We want to better understand how they form, how they absorb light and how they respond to changes in the environment. All that information can help astronomers understand what they’re seeing when they observe these planets.”

The study yielded another surprise: The chemical reactions produced significant amounts of carbon dioxide and water. While water vapor has been found in hot Jupiter atmospheres, scientists for the most part expect this precious molecule to form only when there is more oxygen than carbon. The new study shows that water can form when carbon and oxygen are present in equal amounts. (Carbon monoxide contains one carbon atom and one oxygen atom.) And while some carbon dioxide (one carbon and two oxygen atoms) formed without the addition of UV radiation, the reactions accelerated with the addition of simulated starlight.

“These new results are immediately useful for interpreting what we see in hot Jupiter atmospheres,” said JPL exoplanet scientist Mark Swain, a study coauthor. “We’ve assumed that temperature dominates the chemistry in these atmospheres, but this shows we need to look at how radiation plays a role.”

With next-generation tools like NASA’s James Webb Space Telescope, set to launch in 2021, scientists might produce the first detailed chemical profiles of exoplanet atmospheres, and it’s possible that some of those first subjects will be hot Jupiters. These studies will help scientists learn how other solar systems form and how similar or different they are to our own.

For the JPL researchers, the work has just begun. Unlike a typical oven, theirs seals the gas in tightly to prevent leaks or contamination, and it allows the researchers to control the pressure of the gas as the temperature rises. With this hardware, they can now simulate exoplanet atmospheres at even higher temperatures: close to 3,000 degrees Fahrenheit (1,600 degrees Celsius).

“It’s been an ongoing challenge figuring out how to design and operate this system successfully, since most standard components such as glass or aluminum melt at these temperatures,” said JPL research scientist Bryana Henderson, a coauthor of the study. “We’re still learning how to push these boundaries while safely handling these chemical processes in the lab. But at the end of the day, the exciting results that come out of these experiments is worth all the extra effort.”

Related links:

Astrophysical Journal: https://iopscience.iop.org/article/10.3847/1538-4357/aaf79f/meta

NASA’s James Webb Space Telescope (JWST): https://www.jwst.nasa.gov/

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

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2019 March 15 A View Toward M101 Image Credit & Copyright:…

2019 March 15

A View Toward M101
Image Credit & Copyright: Christoph Kaltseis, CEDIC 2019

Explanation: Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier’s famous catalog, but definitely not one of the least. About 170,000 light-years across, this galaxy is enormous, almost twice the size of our own Milky Way galaxy. M101 was also one of the original spiral nebulae observed by Lord Rosse’s large 19th century telescope, the Leviathan of Parsontown. M101 shares this modern telescopic field of view with more distant background galaxies, foreground stars within the Milky Way, and a companion dwarf galaxy NGC 5474 (lower right). The colors of the Milky Way stars can also be found in the starlight from the large island universe. Its core is dominated by light from cool yellowish stars. Along its grand design spiral arms are the blue colors of hotter, young stars mixed with obscuring dust lanes and pinkish star forming regions. Also known as the Pinwheel Galaxy, M101 lies within the boundaries of the northern constellation Ursa Major, about 23 million light-years away. Its companion NGC 5474 has likely been distorted by its past gravitational interactions with the dominant M101.

∞ Source: apod.nasa.gov/apod/ap190315.html

Chalcopyrite On Siderite | #Geology #GeologyPage…

Chalcopyrite On Siderite | #Geology #GeologyPage #Mineral

Locality: Kalwu Mine, Hezhang County, Bijie Prefecture, Guizhou Province, China (Peoples Republic)

Size: 8 × 4.8 × 3.3 cm

Photo Copyright © Blue Mountains /e-rocks. com

Geology Page



Ammonite | #Geology #GeologyPage #Ammonite #Fossil Age:…

Ammonite | #Geology #GeologyPage #Ammonite #Fossil

Age: Devonian

Location: Atlas Mountains, Morocco

Measuring: 10 ½ x 8 1/2in

Photo Copyright © Bonhams

Geology Page



Boulder Opal with Vivid Green Veining | #Geology #GeologyPage…

Boulder Opal with Vivid Green Veining | #Geology #GeologyPage #Opal #Mineral

Locality: Koroit, Queensland, Australia

Measuring 49.73 x 34.09 x 6.95mm

Photo Copyright © Bonhams

Geology Page



Tourmaline | #Geology #GeologyPage #Mineral Locality: Sapo…

Tourmaline | #Geology #GeologyPage #Mineral

Locality: Sapo Mine, Ferruginha, Conselheiro Pena, Doce Valley, Minas Gerais, Brazil

Size: 2.8 x 0.9 x 0.9 cm

Photo Copyright © Anton Watzl Minerals

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Phantom Quartz | #Geology #GeologyPage #Mineral Locality:…

Phantom Quartz | #Geology #GeologyPage #Mineral

Locality: Schynschlucht, Graubünden, Switzerland

Size: 5.9 x 5.2 x 3.1 cm

Photo Copyright © Anton Watzl Minerals

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Soyuz Docked to Space Station

ROSCOSMOS – Soyuz MS-12 Mission patch.

March 14, 2019

The Soyuz spacecraft carrying NASA astronauts Nick Hague and Christina Koch, and cosmonaut Alexey Ovchinin of Roscosmos docked to the International Space Station at 9:01 p.m. EDT while both spacecraft were flying about 250 miles over the Pacific Ocean just west of Peru. Expedition 59 officially began at the time of docking.

Aboard the space station, NASA astronaut Anne McClain, Expedition 59 Commander Oleg Kononenko of Roscosmos, and David Saint-Jacques of the Canadian Space Agency will welcome the new crew members when the hatches between the two spacecraft are opened following standard pressurization and leak checks.

Image above: Soyuz MS-12 arrived at the International Space Station at 9:01 p.m. ET, 255 miles just west off the coast of Peru. Image Credit: NASA TV.

The crew members will spend more than six months conducting about 250 science investigations in fields such as biology, Earth science, human research, physical sciences, and technology development. Seventy-five of the investigations are new and have never been performed in space. Some of the investigations are sponsored by the U.S. National Laboratory on the space station, which Congress designated in 2005 to maximize its use for improving quality of life on Earth.

Soyuz MS-12 docking

Highlights of upcoming investigations the crew will support include devices that mimic the structure and function of human organs, free-flying robots, and an instrument to measure Earth’s distribution of carbon dioxide.

Watch the hatch opening and welcome ceremony to follow live on NASA TV and the agency’s website beginning at 10:30 p.m.: https://www.nasa.gov/nasalive

Related article:

Crew Safely in Orbit After Successful Launch

Related links:

Expedition 58: https://www.nasa.gov/mission_pages/station/expeditions/expedition58/index.html

Expedition 59: https://www.nasa.gov/mission_pages/station/expeditions/expedition59/index.html

NASA TV: https://www.nasa.gov/live/

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), Video, Text, Credits: NASA/Norah Moran/NASA TV/SciNews.

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Two new papers on ancient Iberia

Olalde et al. 2019 (Science) at this LINK

Abstract: We assembled genome-wide data from 271 ancient Iberians, of whom 176 are from the largely unsampled period after 2000 BCE, thereby providing a high-resolution time transect of the Iberian Peninsula. We document high genetic substructure between northwestern and southeastern hunter-gatherers before the spread of farming. We reveal sporadic contacts between Iberia and North Africa by ~2500 BCE and, by ~2000 BCE, the replacement of 40% of Iberia’s ancestry and nearly 100% of its Y-chromosomes by people with Steppe ancestry. We show that, in the Iron Age, Steppe ancestry had spread not only into Indo-European–speaking regions but also into non-Indo-European–speaking ones, and we reveal that present-day Basques are best described as a typical Iron Age population without the admixture events that later affected the rest of Iberia. Additionally, we document how, beginning at least in the Roman period, the ancestry of the peninsula was transformed by gene flow from North Africa and the eastern Mediterranean. DOI: 10.1126/science.aav4040

Villalba-Mouco et al. 2019 (Current Biology) at this LINK

Summary: The Iberian Peninsula in southwestern Europe represents an important test case for the study of human population movements during prehistoric periods. During the Last Glacial Maximum (LGM), the peninsula formed a periglacial refugium [1] for hunter-gatherers (HGs) and thus served as a potential source for the re-peopling of northern latitudes [2]. The post-LGM genetic signature was previously described as a cline from Western HG (WHG) to Eastern HG (EHG), further shaped by later Holocene expansions from the Near East and the North Pontic steppes [3, 4, 5, 6, 7, 8, 9]. Western and central Europe were dominated by ancestry associated with the ∼14,000-year-old individual from Villabruna, Italy, which had largely replaced earlier genetic ancestry, represented by 19,000–15,000-year-old individuals associated with the Magdalenian culture [2]. However, little is known about the genetic diversity in southern European refugia, the presence of distinct genetic clusters, and correspondence with geography. Here, we report new genome-wide data from 11 HGs and Neolithic individuals that highlight the late survival of Paleolithic ancestry in Iberia, reported previously in Magdalenian-associated individuals. We show that all Iberian HGs, including the oldest, a ∼19,000-year-old individual from El Mirón in Spain, carry dual ancestry from both Villabruna and the Magdalenian-related individuals. Thus, our results suggest an early connection between two potential refugia, resulting in a genetic ancestry that survived in later Iberian HGs. Our new genomic data from Iberian Early and Middle Neolithic individuals show that the dual Iberian HG genomic legacy pertains in the peninsula, suggesting that expanding farmers mixed with local HGs. DOI:https://doi.org/10.1016/j.cub.2019.02.006

See also…
Migration of the Bell Beakers—but not from Iberia (Olalde et al. 2018)
Single Grave > Bell Beakers
CHG or no CHG in Bronze Age western Iberia?


InSight lander among latest ExoMars image bounty

ESA & ROSCOSMOS – ExoMars Mission patch.

14 March 2019

Curious surface features, water-formed minerals, 3D stereo views, and even a sighting of the InSight lander showcase the impressive range of imaging capabilities of the ExoMars Trace Gas Orbiter.

Dust devil frenzy

The ESA-Roscosmos Trace Gas Orbiter, or TGO, launched three years ago today, on 14 March 2016. It arrived at Mars on 19 October that year, and spent over a year demonstrating the aerobraking technique needed to reach its science orbit, starting its prime mission at the end of April 2018.

Hello, InSight

Amongst a new showcase of images from the spacecraft’s Colour and Stereo Surface Imaging System, CaSSIS, is an image of NASA’s InSight lander – the first time a European instrument has identified a lander on the Red Planet.

Insight arrived on Mars on 26 November 2018 to study the interior of the planet. Images of the lander have already been returned by NASA’s Mars Reconnaissance Orbiter; these are the first images from TGO.

ExoMars images InSight

The panchromatic image presented here was captured by CaSSIS on 2 March 2019, and covers an area of about 2.25 x 2.25 km. At that time, InSight was hammering a probe into the surface in order to measure heat coming from inside the planet.

The CaSSIS view shows InSight as a slightly brighter dot in the centre of the dark patch produced when the lander fired its retro rockets, just before touchdown in the Elysium Planitia region of Mars, and disturbed the surface dust. The heat shield released just before landing can also be seen on the edge of a crater, and the backshell used to protect the lander during descent is also identified.

“The ExoMars Trace Gas Orbiter is being used to relay data from InSight to Earth,” says Nicolas Thomas, CaSSIS Principal Investigator, from the University of Bern in Switzerland. “Because of this function, to avoid uncertainties in communications, we had not been able to point the camera towards the landing site so far – we had to wait until the landing site passed directly under the spacecraft to get this image.”

Trace Gas Orbiter (TGO)

CaSSIS is expected to provide additional support to the InSight team by observing the surface of Mars in the area surrounding the lander. If the seismometer picks up a signal, the source might be a meteorite impact. One of CaSSIS’s tasks will be to help search for the impact site, which will allow the InSight team to better constrain the internal properties of Mars near the landing site.

The image of InSight also demonstrates that CaSSIS will be able to take pictures of the future ExoMars mission. The mission comprises a rover – named Rosalind Franklin – together with a surface science platform, and is due to be launched in July 2020, arriving at Mars in March 2021. TGO will also act as the data relay for the rover.

Salty sulphates

Science showcase

Also released today is a selection of images capturing the impressive science capabilities of CaSSIS, ranging from high-resolution views of intriguing surface features and images that highlight the diversity of minerals on the surface, to 3D stereo views and digital terrain models.

The images selected include detailed views of layered deposits in the polar regions, the dynamic nature of Mars dunes, and the surface effects of converging dust devils. The stereo images bring the scenes alive by providing an extra insight into elevation differences, which is essential for deciphering the history in which different layers and deposits were laid down.

Colour-composite images are processed to better highlight the contrast of surface features. Combined with data from other instruments, this allows scientists to trace out regions that have been influenced by water, for example. These images can also be used to help guide surface exploration missions and provide broader regional context for landers and rovers.

Ascraeus Mons – digital terrain model

“The InSight landing site image is just one of many really high quality images that we have been receiving,” adds Nicolas. “All of the images we’re sharing today represent some of the best from the last few months. We’re also really pleased with the digital terrain models.”

Draped dunes – 3D

“This stunning image showcase really demonstrates the scientific potential we have with TGO’s imaging system,” says Håkan Svedhem, ESA’s TGO project scientist. “Over the course of the mission we’ll be able to investigate dynamic surface processes, including those that might also help to constrain the atmospheric gas inventory that TGO’s spectrometers have been analysing, as well as characterise future landing sites.” 

South polar layered terrains

Notes for editors

The images have been produced by teams from the University of Bern, Switzerland; the University of Arizona, USA; and INAF-Padova, Italy.

Read the University of Bern press release here: https://www.unibe.ch/news/media_news/media_relations_e/media_releases/2019/medienmitteilungen_2019/bernese_mars_camera_cassis_returns_spectacular_images/index_eng.html

Related links:

ExoMars: http://www.esa.int/Our_Activities/Human_and_Robotic_Exploration/Exploration/ExoMars

CaSSIS: http://www.cassis.unibe.ch/

NASA’s InSight: https://mars.nasa.gov/insight/

Images, Text, Credits: ESA/Markus Bauer/Håkan Svedhem/Center for Space and Habitability (CSH)
University of Bern, Nicolas Thomas/Roscosmos/CaSSIS, CC BY-SA 3.0 IGO.

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ESA greenlight for UK’s air-breathing rocket engine

ESA – European Space Agency patch.

14 March 2019

Vehicle Two Stage to Orbit

The development programme of the world’s first air-breathing rocket engine has taken an additional significant step forward, which will lead to major testing milestones being undertaken within the next 18 months.

SABRE engine core

ESA, together with the UK Space Agency (UKSA) recently reviewed the preliminary design of the demonstrator engine core of the Synergetic Air-Breathing Rocket Engine (SABRE), which Reaction Engines will use to undertake ground-based testing at test facility at Westcott, Buckinghamshire, which is currently under construction.

“The positive conclusion of our preliminary design review marks a major milestone in SABRE development,” comments Mark Ford, heading ESA’s Propulsion Engineering section. “It confirms the test version of this revolutionary new class of engine is ready for implementation.”

SABRE engine

SABRE is uniquely designed to scoop up atmospheric air during the initial part of its ascent to space at up to five times the speed of sound. At about 25 km it would then switch to pure rocket mode for its final climb to orbit.

In future SABRE could serve as the basis of a reusable launch vehicle that operates like an aircraft. Because it would carry much less bulky onboard oxygen supplies, such a vehicle could deliver the same payload to orbit of a half the vehicle mass of current launchers, as well as potentially offering a large reduction in cost and higher launch rate.

Engine airflow

ESA, via the UK Space Agency has invested €10 million in SABRE development, together with £50 million from UKSA. ESA also performs a technical oversight role on behalf of UKSA.

ESA’s involvement began in 2010 with an independent review of SABRE’s viability, opening the way to UK government investment. Then, in 2012, ESA collaborated with Reaction Engines on testing of an essential element of SABRE – the pre-cooler that cools the hot airstream entering the engine at hypersonic speed, the performance of which was fully validated under ambient air temperatures.

Precooler testing for SABRE engine

Reaction Engines launched a significant new element of its development programme in October 2016 to design, build and demonstrate a SABRE engine core. The test item consists of an engine core, which is a key module of the complete SABRE engine, but without the pre-cooler and rocket nozzle in place. Following completion of this core design and development activity major elements of the world’s first air-breathing engine capable of accelerating from zero to Mach 5 will have been demonstrated.

The complete air-breathing core demonstrator will be fully representative of the SABRE thermodynamic core cycle, fuelled by liquid hydrogen, and will contain heat exchangers plus combustion and turbomachinery modules.

Westcott rocket engine site

Testing of the core demonstrator will be undertaken at a dedicated test facility currently being built at Westcott Venture Park in Buckinghamshire, a historic site for British rocketry where engines for the Blue Streak and Black Arrow rockets were tested.

Chris Castelli, Director of Programmes at the UK Space Agency, said: “As the home of the jet engine, the UK has a rich aerospace heritage and world-renowned skills and expertise. This is an exciting landmark for Reaction Engines in the development of its SABRE engine, which could revolutionise both access to space and international travel by powering aircraft to five times the speed of sound.

TF1 time lapse – August 2018

“The government’s modern industrial strategy is putting the UK at the forefront of pioneering aerospace technologies and ensuring we thrive in the new commercial space age. Our £60m investment in SABRE is a great example of how we are backing the businesses of tomorrow.”

Shaun Driscoll, Programmes Director atReaction Engines, said:“Reaction Engines has had a hugely supportive relationship with ESA and we are delighted with this further endorsement of the SABRE engine design. This step opens the door to some exciting testing milestones which we will be undertaking in the next 18 months and moves us closer to the demonstration of the first SABRE engine, a unique class of scalable aerospace engines, which will revolutionise the way we travel around the globe, and get into orbit.” 

Sabre Animation 2017

“One of the great advantages of the SABRE propulsion concept is that it is totally modular from both design and operational perspectives” explains Richard Varvill, Chief Technology Officer of Reaction Engines. “Therefore it is possible to subject each of the key components of the engine to rigorous ground testing, which fully mimic the operational conditions the engine will face up to Mach 5 flight at 25km altitude.”  

Related links:

Space Engineering & Technology: http://www.esa.int/Our_Activities/Space_Engineering_Technology

Reaction Engines Limited: http://www.reactionengines.co.uk/

UK Space Agency: http://www.bis.gov.uk/ukspaceagency

Images, Videos, Text, Credits: ESA/Reaction Engines Ltd.

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Researchers uncover additional evidence for massive solar storms

Solar storms can be far more powerful than previously thought. A new study has found evidence for the third known case of a massive solar storm in historical times. The researchers believe that society might not be sufficiently prepared if a similar event were to happen now.

Researchers uncover additional evidence for massive solar storms
Credit: NASA/SDO and the AIA, EVE, and HMI science teams

Our planet is constantly being bombarded by cosmic particles. However, at times the stream of particles is particularly strong when a solar storm sweeps past. Solar storms are made up of high-energy particles unleashed from the sun by explosions on the star’s surface.

For the past 70 years, researchers have studied these solar storms by direct instrumental observations, which has led to an understanding of how they can pose a risk to the electrical grid, various communication systems, satellites and air traffic. Two examples of severe solar storms in modern times that caused extensive power cuts took place in Quebec, Canada, (1989) and Malmö, Sweden (2003).

Now, an increasing amount of research indicates that solar storms can be even more powerful than measurements have shown so far via direct observations.

The researchers behind the new, international study led by researchers from Lund University have used drilled samples of ice, or ice cores, to find clues about previous solar storms. The cores come from Greenland and contain ice formed over the past about 100 000 years. The material contains evidence of a very powerful solar storm that occurred in 660 BCE.

“If that solar storm had occurred today, it could have had severe effects on our high-tech society”, says Raimund Muscheler, professor of geology at Lund University.

The new study means that a third known case of a massive solar storm dating back in time has been discovered via indirect observations in nature’s own archive. Raimund Muscheler also took part in research that confirmed the existence of two other massive solar storms, using both ice cores and the annual growth rings of old trees. These storms took place in 775 and 994 CE.

Raimund Muscheler points out that, even though these massive solar storms are rare, the new discovery shows that they are a naturally recurring effect of solar activity.

“That’s why we must increase society’s protection again solar storms”, he says.

Today’s risk assessment is largely based on direct observations made over the past 70 years, but Raimund Muscheler suggests that there is a need for a reassessment in view of the three massive solar storms that have now been discovered. He argues that there is a need for greater awareness of the possibility of very strong solar storms and the vulnerability of our society.

“Our research suggests that the risks are currently underestimated. We need to be better prepared”, concludes Raimund Muscheler.

The findings are published in the Proceedings of the National Academy of Sciences.

Source: Lund University [March 11, 2019]




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