четверг, 14 марта 2019 г.

Mammoth moves: frozen cells come to life, but only just

A team of scientists in Japan has successfully coaxed activity from 28,000-year-old cells from a frozen mammoth implanted into mouse cells, but the woolly mammal is unlikely to be walking among us soon.











Mammoth moves: frozen cells come to life, but only just
Cells from a woolly mammoth that died 28,000 years ago have shown signs of activity
after being implanted in mice [Credit: Reuters]

The project by an international team took cell nuclei from a well-preserved mammoth discovered in 2011 in Siberian permafrost and placed them into several dozen mouse egg cells.


Of those, five displayed the biological reactions that happen just before cell division begins, said Kei Miyamoto, a member of the team at Kindai University in western Japan.


None, however, produced the actual cell division needed for a mammoth rebirth, the researcher told AFP.


“This suggests that, despite the years that have passed, cell activity can still happen and parts of it can be recreated,” he told AFP.


“Until now many studies have focused on analysing fossil DNA and not whether they still function,” he added.


The research — published in the journal Scientific Reports — doesn’t provide much hope for Jurassic Park-style resurrection of long-extinct species just yet, he cautioned.


“We have also learned that damage to cells was very profound.”


“We are yet to see even cell divisions. I have to say we are very far from recreating a mammoth.”


The university has worked with other Japanese and Russian institutes to study and to possibly clone the mammoth and plans to study alternative methods to bring the prehistoric giant back to life.


“We need new technology, we want to try various approaches,” Miyamoto said.


Source: AFP [March 12, 2019]



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Researchers unravel mysteries of Earth’s inner core

Researchers from The Australian National University (ANU) are unlocking some of the secrets of the Earth’s inner core by adapting and further developing a technique used in hospitals around the world.











Researchers unravel mysteries of Earth's inner core
Credit: Flickr, Iain Logan

Tomography is the imaging process used in x-rays and ultrasounds, and involves waves passing through the body, before bouncing off body tissue and back to a receiver.


ANU researcher Professor Hrvoje Tkalčić said it’s also turned out to be a useful way for seismologists to “see” inside the Earth – with a couple of key differences.


“This is one of the first attempts at tomography of the Earth’s inner core.”


“In medicine they have an infinite number of sources and receivers they can place around the body, depending on the problem area. Earth scientists have to rely on natural sources – or earthquakes – and seismometers, and we don’t have full control over their location.”


“One of the key things we can measure is the travel time of waves through the planet, from the time a large earthquake happens to when it gets recorded by the instrument on the other side of the globe.”


This travel time, and how much the waves attenuate – or lose energy – can provide crucial information about the material they’re passing through, in the same way x-rays can pick up abnormal structures in the human body.


The ANU team used a ground breaking method to improve the accuracy of their results, employing a complex computer algorithm.


“We used what’s called a “trans-dimensional” algorithm. This means the dimension of our problem is changing as we are solving it, or in other words the number of unknowns in our problem is itself an unknown,” Dr Tanja Pejić said.


“This is a highly computationally complex problem, with individual computations taking weeks to solve on the RSES’s Terrawulf computer cluster. The answer is a whole ensemble of solutions, and averaging through it gives us a statistically more likely solution.”


The study focused on imaging the top layer of the Earth’s inner core, an area seen by some scientists as a ‘final frontier’ of global seismology.


“For the past few decades scientists have been locked in a debate about the inner core’s formation, dynamics, and growth,” Dr Pejić said.


“Our paper shows that the eastern hemisphere is highly attenuative for seismic waves, but also that the western hemisphere – instead of being less attenuative – can be further divided into two regions. One region is potentially even more attenuative than all of the eastern hemisphere, and the other region is less attenuative.”


Professor Tkalčić said these findings could provide new evidence about the connection between the inner core and other parts of the earth.


“We can learn from these tomographic images something about the dynamics of the entire system, the entire core and its connection to the lower mantle and the surface of the Earth.”


“Even though this is a snapshot of the current view of the Earth, it could help us better understand the formation process of the solid inner core, and even planetary formation in general.”


“We are slowly getting there.”


The research has been published in the Journal of Geophysical Research: Solid Earth.


Author: Jessica Fagan | Source: Australian National University [March 13, 2019]



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The day the world burned: Evidence of major cosmic impact 12,800 years ago found in Chile

When UC Santa Barbara geology professor emeritus James Kennett and colleagues set out years ago to examine signs of a major cosmic impact that occurred toward the end of the Pleistocene epoch, little did they know just how far-reaching the projected climatic effect would be.











The day the world burned: Evidence of major cosmic impact 12,800 years ago found in Chile
Credit: UC Santa Barbara

“It’s much more extreme than I ever thought when I started this work,” Kennett noted. “The more work that has been done, the more extreme it seems.”


He’s talking about the Younger Dryas Impact Hypothesis, which postulates that a fragmented comet slammed into the Earth close to 12,800 years ago, causing rapid climatic changes, megafaunal extinctions, sudden human population decrease and cultural shifts and widespread wildfires (biomass burning). The hypothesis suggests a possible triggering mechanism for the abrupt changes in climate at that time, in particular a rapid cooling in the Northern Hemisphere, called the Younger Dryas, amid a general global trend of natural warming and ice sheet melting evidenced by changes in the fossil and sediment record.


Controversial from the time it was proposed, the hypothesis even now continues to be contested by those who prefer to attribute the end-Pleistocene reversal in warming entirely to terrestrial causes. But Kennett and fellow stalwarts of the Younger Dryas Boundary (YDB) Impact Hypothesis, as it is also known, have recently received a major boost: the discovery of a very young, 31-kilometer-wide impact crater beneath the Greenland ice sheet, which they believe may have been one of the many comet fragments that impacted Earth at the onset of the Younger Dryas.


Now, in a paper published in the journal Nature Scientific Reports, Kennett and colleagues, led by Chilean paleontologist Mario Pino, present further evidence of a cosmic impact, this time far south of the equator, that likely lead to biomass burning, climate change and megafaunal extinctions nearly 13,000 years ago.


“We have identified the YDB layer at high latitudes in the Southern Hemisphere at near 41 degrees south, close to the tip of South America,” Kennett said. This is a major expansion of the extent of the YDB event.” The vast majority of evidence to date, he added, has been found in the Northern Hemisphere.


This discovery began several years ago, according to Kennett, when a group of Chilean scientists studying sediment layers at a well-known Quaternary paleontological and archaeological site, Pilauco Bajo, recognized changes known to be associated with YDB impact event. They included a “black mat” layer, 12,800 years in age, that coincided with the disappearance of South American Pleistocene megafauna fossils, an abrupt shift in regional vegetation and a disappearance of human artifacts.











The day the world burned: Evidence of major cosmic impact 12,800 years ago found in Chile
The researchers found evidence of cosmic impact at the Pilauco dig site in a suburb
of the Osorno province in Chile [Credit: UC Santa Barbara]

“Because the sequencing of these events looked like what had already been described in the YDB papers for North America and Western Europe, the group decided to run analyses of impact-related proxies in search of the YDB layer,” Kennett said. This yielded the presence of microscopic spherules interpreted to have been formed by melting due to the extremely high temperatures associated with impact. The layer containing these spherules also show peak concentrations of platinum and gold, and native iron particles rarely found in nature.


“Among the most important spherules are those that are chromium-rich,” Kennett explained. The Pilauco site spherules contain an unusual level of chromium, an element not found in Northern Hemisphere YDB impact spherules, but in South America. “It turns out that volcanic rocks in the southern Andes can be rich in chromium, and these rocks provided a local source for this chromium,” he added. “Thus, the cometary objects must have hit South America as well.”


Other evidence, which, Kennett noted, is consistent with previous and ongoing documentation of the region by Chilean scientists, pointed to a “very large environmental disruption at about 40 degrees south.” These included a large biomass burning event evidenced by, among other things, micro-charcoal and signs of burning in pollen samples collected at the impact layer. “It’s by far the biggest burn event in this region we see in the record that spans thousands of years,” Kennett said. Furthermore, he went on, the burning coincides with the timing of major YDB-related burning events in North America and western Europe.


The sedimentary layers at Pilauco contain a valuable record of pollen and seeds that show change in character of regional vegetation — evidence of a shifting climate. However, in contrast to the Northern Hemisphere, where conditions became colder and wetter at the onset of the Younger Dryas, the opposite occurred in the Southern Hemisphere.


“The plant assemblages indicate that there was an abrupt and major shift in the vegetation from wet, cold conditions at Pilauco to warm, dry conditions,” Kennett said. According to him, the atmospheric zonal climatic belts shifted “like a seesaw,” with a synergistic mechanism, bringing warming to the Southern Hemisphere even as the Northern Hemisphere experienced cooling and expanding sea ice. The rapidity — within a few years — with which the climate shifted is best attributed to impact-related shifts in atmospheric systems, rather than to the slower oceanic processes, Kennett said.


Meanwhile, the impact with its associated major environmental effects, including burning, is thought to have contributed to the extinction of local South American Pleistocene megafauna — including giant ground sloths, sabretooth cats, mammoths and elephant-like gomphotheres — as well as the termination of the culture similar to the Clovis culture in the north, he added. The amount of bones, artifacts and megafauna-associated fungi that were relatively abundant in the soil at the Pilauco site declined precipitously at the impact layer, indicating a major local disruption.


The distance of this recently identified YDB site — about 6,000 kilometers from the closest well-studied site in South America — and its correlation with the many Northern Hemispheric sites “greatly expands the extent of the YDB impact event,” Kennett said. The sedimentary and paleo-vegetative evidence gathered at the Pilauco site is in line with previous, separate studies conducted by Chilean scientists that indicate a widespread burn and sudden major climate shifts in the region at about YDB onset. This new study further bolsters the hypothesis that a cosmic impact triggered the atmospheric and oceanic conditions of the Younger Dryas, he said.


“This is further evidence that the Younger Dryas climatic onset is an extreme global event, with major consequences on the animal life and the human life at the time,” Kennett said. “And this Pilauco section is consistent with that.”


Author: Sonia Fernandez | Source: University of California – Santa Barbara [March 13, 2019]



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Changes in rat size reveal habitat of ‘Hobbit’ hominin

A study of rat body sizes shifting over time gives a glimpse into the habitat of the mysterious hominin Homo floresiensis — nicknamed the “Hobbit” due to its diminutive stature.











Changes in rat size reveal habitat of 'Hobbit' hominin
At the Liang Bua cave site, paleoanthropologist Matthew Tocheri, left, measures a modern giant rat with the
 assistance of Bonefasius Sagut. At right is a reconstruction of Homo floresiensis carrying a giant rat,
by paleo artist Peter Schouten [Credit: Peter Schouten]

The Journal of Human Evolution is publishing the study, based on an analysis of thousands of rodent bones, mainly fore- and hind-limbs, from an Indonesian cave where H. floresiensis was discovered in 2003. The results indicate that the local habitat was mostly open grasslands more than 100,000 years ago, but began shifting rapidly to a more closed environment 60,000 years ago.


“Our paper is the first that we know of to use the leg bones of rats in this way to interpret ecological change through time, and it provides new evidence for the local environment during the time of Homo Floresiensis,” says Elizabeth Grace Veatch, a PhD candidate at Emory University and a first author of the study.


H. floresiensis stood only about 3 feet 6 inches tall and was known to have lived about 190,000 to 50,000 years ago on the oceanic island of Flores in eastern Indonesia. The tiny hominin shared the island with animals that could have come from the pages of a Tolkien novel, including giant Komodo dragons, six-foot-tall storks, vultures with a six-foot wingspan, and pygmy Stegodons — herbivores that looked like small elephants with swooping, oversized tusks. It was the rats, however, that most interested Veatch.


Murids, as the rat family is known, are more taxonomically diverse than any other mammal group and are found in nearly every part of the world. “They exhibit an incredible range of behaviors occupying many different ecological niches,” Veatch says. “And because small mammals are typically sensitive to ecological shifts, they can tell you a lot about what’s going on in an environment.”


The study was based on remains recovered from the limestone cave known as Liang Bua, where partial skeletons of H. floresiensis have been found, along with stone tools and the remains of animals — most of them rats. In fact, out of the 275,000 animal bones identified in the cave so far, 80 percent of them are from rodents.


Veatch came to Emory to work with paleoanthropologist Jessica Thompson, a leading expert in using taphonomy — the study of what happens to bones after an organism dies — to learn more about the evolution of the human diet. Although Thompson has now moved to Yale University, she continues to mentor Veatch in her graduate studies at Emory.











Changes in rat size reveal habitat of 'Hobbit' hominin
Graphic image of the Liang Bua rat species used in the study
[Credit: E. Grace Veatch et al. 2019]

Veatch became part of the Liang Bua project while doing an internship with the Human Origins Program of the Smithsonian Institution’s National Museum of Natural History. Her mentor there was paleoanthropologist Matthew Tocheri (now with Lakehead University in Ontario) who shares first-authorship of the current paper with Veatch.


“Matthew asked me if I wanted to analyze some rat bones and I said, ‘Sure,'” Veatch recalls. “I had no idea what I was getting into.”


The study encompassed about 10,000 of the Liang Bua rat bones. The remains spanned five species with distinct sizes, from the mouse-sized Rattus hainaldi up to the housecat-sized Papagomys armandvillei — commonly known as the Flores giant rat. After categorizing the bones, the researchers could then directly link them to both species and environmental types.


While rats can adjust to new environments, the morphologies of different species tend to be adaptive to their preferred environment. For example, the habitat of the medium-sized Komodomys rintjanus, included in the study, is primarily open grasslands intermittent with patches of forest. In contrast, the tiny R. hainaldi and the giant P. armandvillei both prefer more closed or semi-closed forested habitats.


Tracking the relative abundances of the different rat species over time indicated that the local ecology was mostly open grassland 100,000 years ago, transitioning to a more-closed, forested habitat around 60,000 years ago. That is around the same time that skeletal elements belonging to Homo floresiensis, the pygmy Stegodon, giant storks, vulture and Komodo dragons disappear from Liang Bua.


“The evidence suggests that Homo floresiensis may have preferred more open habitats where they may have been a part of this scavenging guild of Stegodons, storks and vultures,” Veatch says. “We think that when the habitat changed, becoming more forested, Homo floresiensis probably left the Liang Bua area, tracking these animals to more open habitats elsewhere on the island.”











Changes in rat size reveal habitat of 'Hobbit' hominin
Veatch looks at piles of sediment excavated from Luang Bua as it is being wet sieved using
the irrigation system of a rice paddy near the cave site [Credit: Hanneke Meijer]

Many more mysteries remain regarding H. floresiensis, Veatch says, and the Liang Bua rat bones may help solve some of them. One key question is whether H. floresiensis hunted small game.


“Our early ancestors adapted to consuming large amounts of big game through hunting or scavenging — or both,” Veatch says. “Big game undoubtedly became a critical food source, resulting in numerous social and physiological adaptations, including social cooperation and brain expansion. It’s much less known, however, what role small-game hunting may have played in our early evolution — if any at all.”


Liang Bua, she says, offers an ideal opportunity to study what a small-brained hominin, like H. floresiensis, might hunt if it had both sources of big game, like the Stegodon, and small game, like the giant Flores rat and other rat species.


Veatch is conducting field studies at the Liang Bua site, including running experiments to determine how difficult it would be to capture wild Flores rats. She is also doing research at the Pusat Penelitian Arkeologi Nasional (ARKENAS) Museum in the Indonesian capital of Jakarta where many of the bones from the cave site are now stored. She is analyzing a large sample of the bones to determine if any have cut marks — indicating butchering with tools — or pitted marks that would indicate they were digested by owls or other raptors that may have deposited them in the cave.


“In Indonesia, my nickname is Miss Tikus, which means ‘Miss Rat,'” Veatch says. “I’m perfectly fine with that because rats are really intelligent and extraordinary animals. We see them through the entire sequence in the archaeology of Liang Bua and we will continue to use them in future studies to learn more about what went on in the cave.”


Author: Carol Clark | Source: Emory University [March 13, 2019]



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Pig remains reveal extensive human mobility to sites near Stonehenge

A mutli-isotope analysis of pigs remains found around henge complexes near Stonehenge has revealed the large extent and scale of movements of human communities in Britain during the Late Neolithic.











Pig remains reveal extensive human mobility to sites near Stonehenge
Stonehenge, Wiltshire [Credit: (c) Dave White]

The findings “demonstrate a level of interaction and social complexity not previously appreciated,” the authors say, and provide insight into more than a century of debate surrounding the origins of people and animals in the Stonehenge landscape.


Neolithic henge complexes, located in southern Britain, have long been studied for their role as ceremonial centers. Feasts that were unprecedented at the time were held at these locations.


Experts have theorized that these events brought in many people beyond the surrounding area of the henge sites, but little is known about the scale and extent of movement surrounding these feasts. Pigs were the main delicacy at these events.


Here, taking advantage of how isotope analyses can provide insight into pig origins and thus serve as a good proxy for human movement, Richard Madgwick and colleagues undertook a multi-isotope approach on 131 pig remains from four Late Neolithic henge complex sites in central southern England.


The authors incorporated origin data relating to geology (strontium, 87Sr/86Sr), climate (oxygen, δ18O), and coastal proximity (sulfur, δ34S), while taking into account the impact of diet on these values (δ13C and δ15N).


Laboratory work preparing bone and teeth samples for isotope analysis [Credit: Cardiff University]


The isotope values were wide-ranging, particularly in the three isotopes most applicable to mobility – 87Sr/86Sr, δ34S and δ18O. The 87Sr/86Sr values cover all the biospheres of Britain.


The 45 pig samples studied showed evidence of marine influence in their δ34S values, which the authors say is notable considering these henge sites are more than 50 kilometers from the closest coast.


The δ13C data also showed a large range, indicating that the animals were raised in diverse landscapes.


Madgwick et al. say that their results are strongly indicative of extensive movement of people and their pigs during this period.


The study is published in Science Advances.


Source: American Association for the Advancement of Science [March 13, 2019]



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Strontium isotope maps are disturbed by agricultural lime

A study by researchers at Department of Geoscience, Aarhus University, Denmark now shows that strontium isotopes may often be used incorrectly in archaeological studies, as the widespread use of added (strontium-rich) agricultural lime in low- to non-calcareous soils can dramatically alter the strontium isotopic composition of the surface waters running through them and the plants growing within them.











Strontium isotope maps are disturbed by agricultural lime
Pristine Vallerbaek valley during fieldwork [Credit: Tine Rasmussen]

This is of special significance for strontium-isotope based provenance studies, where the strontium isotopic values measured in a prehistoric person’s remains or in a given artefact are compared to measured strontium isotopic values in the surrounding, modern environment.
Reference maps showing strontium isotope data dominated by the isotopic signature of modern agricultural lime, do not show the true strontium isotopic composition of the area during prehistoric times, when the individual being studied lived., or the object being studied was in created.


This can result in erroneous interpretations of the origin and movement of these prehistoric people and artefacts.











Strontium isotope maps are disturbed by agricultural lime
According to the new study, the concentration of strontium increases as the river passes through areas
 where there is agriculture [Credit: Thomsen et al. 2019]

In their study published in Science Advances, the geologists Erik Thomsen and Rasmus Andreasen from Aarhus University discuss two prominent examples of this:
The iconic Bronze Age women, the Egtved Girl and the Skrydstrup Woman, who were found in Denmark in 1921 and 1935 respectively, but were recently (2015 & 2017) interpreted to have originated far away from Denmark. Moreover, the Egtved Girl was interpreted by the study’s authors to have traveled back and forth between Denmark and another place, likely her homeland that was believed to be southern Germany.


Flyby of Vallerbaek Stream-Karup River with strontium data superimposed 
[Credit: Rasmus Andreasen]


Video summary of study [Credit: Erik Thomsen, Tine Rasmussen]


These conclusions became a part of a larger framework of ideas of extended European mobility, migration, and trade, during the Bronze Age.
Conversely, the strontium data presented in the new study show that these two women could have obtained their strontium isotopic signatures within 10 km of their burial mounds, and do not indicate any cause to suspect that the women came from afar or travelled great distances during their lifetimes.











Strontium isotope maps are disturbed by agricultural lime
The Skrydstrup woman is one of the very best preserved finds we have from the Bronze Age. In recent years,
researchers have thought that she came from afar, but it is not certain, says the new study
[Credit: 
National Museum of Denmark]

It is noteworthy that the effects of agricultural lime on the strontium isotopic composition demonstrated here is not isolated to this study’s field areas in western Denmark but is likely to occur worldwide in arable areas with non-calcareous soils.


The use of agricultural lime is ubiquitous in farming on less fertile soils to provide calcium for the plants and adjust soil acidity. Thus, many studies using strontium isotopes for provenance and mobility studies in these farmed low-calcareous areas may well need revision, and researchers should use care when sampling in these areas for such studies, in the future.


Source: Aarhus University [March 13, 2019]



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2019 March 14 Perseverance Valley Panorama Image Credit: NASA…


2019 March 14


Perseverance Valley Panorama
Image Credit: NASA JPL-Caltech Cornell ASU


Explanation: Mars exploration rover Opportunity’s parting panorama from Perseverance Valley spans 360 degrees in this false color mosaic. The scene is composed of 354 individual images recorded through 3 different color filters by the rover’s panoramic camera from May 13 through June 10, 2018. A few frames remain in black and white at the lower left though. Those were obtained through only one filter just before a dust storm engulfed Mars in June 2018, ultimately ending the solar-powered rover’s trailblazing 15 year mission. Just right of center, the annotation identifies Opportunity’s entry point to Perseverance Valley along the Endeavor crater’s western rim. The rover’s tracks begin there, extending from over the horizon toward the far right and its final resting spot on the Red Planet.


∞ Source: apod.nasa.gov/apod/ap190314.html


LS2 Report: Rejuvenation for the Antiproton Decelerator


CERN – European Organization for Nuclear Research logo.


13 March, 2019


The Antiproton Decelerator will see refurbishment work that will help its experiments to trap more antimatter than before 



The AD target area during LS2 (Image: Maximilien Brice/CERN)

The Antiproton Decelerator (AD), sometimes known as the Antimatter Factory, is the world’s largest source of antimatter and has been operational since 2000. Here, antiprotons are slowed down and sent into the experiments, where they are combined with antielectrons to produce the most basic antiatom: that of antihydrogen. Over the course of the second long shutdown of CERN’s accelerator complex (LS2), the AD will receive several enhancements as well as repairs and refurbishments.


The recently installed ELENA ring, which was commissioned over 2017 and 2018, is designed to slow down even further the antiprotons decelerated by AD to ensure that the experiments can trap up to 100 times more antiprotons than they could without it. At the moment, ELENA is only connected to one of the experiments within the AD hall, the new GBAR experiment. The main work being done on the AD during the next two years is to extend the beam line from ELENA to all of the existing experiments and get ELENA fully operational. The lines that took the particles from the AD to the experiments have now been fully dismantled to prepare for the new injection lines from ELENA.


Other planned and ongoing activities involve the AD’s 84 magnets, which focus and steer the whizzing antiprotons along their racetrack. Most of these magnets were recycled from previous accelerator facilities and are much older than the AD itself. They are in need of repairs and refurbishment, which started during the previous long shutdown (LS1) and was pursued during subsequent year-end technical stops (YETS). So far, nine of the magnets have been treated, and 20 of them are scheduled for treatment during LS2. The remaining magnets will either be treated in situ or will undergo refurbishment during the next YETS and the third long shutdown (LS3).


Removing the magnets to take them to the treatment facility is no easy task. The AD ring is encased in a large shielding tunnel made of concrete blocks. Therefore, the blocks making up the ceiling near the magnet in question have to first be removed and stored, allowing a crane to descend though the opening and extract the magnet (which weighs up to 26 tonnes), sometimes with a margin of only 1 cm. Related work is being done to consolidate other elements of the AD, such as the kicker magnets, the septa magnets and the radiofrequency cavities.


One of the main tasks of LS2 that has already been achieved was the installation of a new cooling pump for the AD. Previously, a single set of pumps were operated, connected to both the AD itself and to its experiments. This meant that the pumping system was operational year round next to the AD ring, producing a constant noise at over 100 decibels in some places. The new dedicated pump allows the main pumping group to be turned off without affecting the experiments’ cooling systems, saving money and improving working conditions for those who need to be in close proximity to the AD over the shutdown period. It also provides much-needed redundancy to the cooling circuits.


By the end of LS2, the AD hall will look very different from what it does today, but the changes are not merely superficial. They will ensure that CERN’s antimatter factory continues to operate with high efficiency and help explore the mysteries surrounding elusive antimatter.


Note:


CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.


The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.


Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.


Related links:


Antiproton Decelerator (AD): https://home.cern/science/accelerators/antiproton-decelerator


ELENA ring: https://home.cern/tags/elena


Previous long shutdown (LS1): https://home.cern/tags/long-shutdown-1


For more information about European Organization for Nuclear Research (CERN), Visit: https://home.cern/


Image (mentioned), Text, Credits: CERN/Achintya Rao.


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Astronomers Discover 83 Supermassive Black Holes in the Early Universe


Figure 1: Light from one of the most distant quasars known, powered by a SMBH lying 13.05 billion light-years away from Earth. The image was obtained by the Hyper Suprime-Cam (HSC) mounted on the Subaru Telescope. The other objects in the field are mostly stars in our Milky Way, and galaxies seen along the line of sight. (Credit: NAOJ)


A team of astronomers has discovered 83 quasars powered by supermassive black holes (SMBHs) in the distant universe, from an epoch when the universe was less than 10 percent of its present age. This finding was made by using the wide-field camera Hyper Suprime-Cam (HSC) mounted on the Subaru Telescope. The discovery increases the number of black holes known at that epoch considerably, and reveals, for the first time, how common SMBHs are early in the universe’s history. In addition, it provides new insight into the effect of black holes on the physical state of gas in the early universe in its first billion years. Figure 1 shows an example of a discovered SMBH.


Supermassive black holes are found at the centers of galaxies, and have masses millions or even billions of times that of the Sun. While they are prevalent in the present-day universe, it is unclear when they first formed, and how many of them exist in the distant early universe. While distant SMBHs are identified as quasars, which shine as gas accretes onto them (see Figure 2 for an artist impression), previous studies have been sensitive only to the very rare most luminous quasars, and thus the most massive black holes. The new discoveries probe the population of SMBH with masses characteristic of the most common black holes seen in the present-day universe, and thus shed light on their origin.






Figure 2: An artist impression of a quasar. A SMBH sits at the center, and the gravitational energy of material accreting onto the SMBH is released as light. (Credit: Yoshiki Matsuoka)



The research team led by Yoshiki Matsuoka (Ehime University) used data taken with a cutting-edge instrument, Hyper Suprime-Cam (HSC), mounted on the Subaru Telescope of the National Astronomical Observatory of Japan, on the summit of Maunakea in Hawai’i. HSC is particularly powerful in that it has a gigantic field-of-view of 1.77 deg2 (seven times the area of the Full Moon), mounted on one of the largest telescopes in the world. The HSC team is carrying a survey of the sky using 300 nights of telescope time, spread over five years. The team selected distant quasar candidates from the sensitive HSC survey. They then carried out an intensive observational campaign to obtain spectra of those candidates, using the Subaru Telescope, the Gran Telescopio Canarias, and the Gemini telescope. The survey has revealed 83 previously unknown very distant quasars; together with the 17 quasars already known in the survey region, Matsuoka and collaborators found that there is roughly one supermassive black hole in each cube a billion light years on a side. Figure 3 shows images of the 100 quasars identified from the HSC data.




Figure 3: The 100 quasars identified from the HSC data. The top seven rows represent the 83 new discoveries, while the bottom two rows represent 17 previously known quasars in the survey area. They appear extremely red due to the cosmic expansion and absorption of light in intergalactic space. All the images were obtained by HSC. (Credit: NAOJ)



The discovered quasars are about 13 billion light-years away from the Earth; in other words, we are seeing them as they existed 13 billion years ago. The time elapsed since the Big Bang to that cosmic epoch is only 5 per cent of the present cosmic age (13.8 billion years), and it is remarkable that such massive dense objects were able to form so soon after the Big Bang. The most distant quasar discovered by the team is 13.05 billion light-years away, which is tied for the second most distant SMBH ever discovered.


It is widely accepted that the hydrogen in the universe was once neutral, but was “reionized” (i.e., split into its component protons and electrons) around the epoch when the first generation of stars, galaxies, and SMBHs were born, in the first few hundred million years after the Big Bang. This is a milestone of cosmic history, but it is still not clear what provided the incredible amount of energy required to cause the reionization. A compelling hypothesis suggests that there were many more quasars in the early universe than detected previously, and it is their integrated radiation that reionized the universe. However, the number density measured by the HSC team clearly indicates that this is not the case; the number of quasars seen is significantly less than needed to explain the reionization. Reionization was therefore caused by another energy source, most likely numerous galaxies that started to form in the young universe.


The present study was made possible by the world-leading survey ability of Subaru and HSC. The intensive follow-up observations by the Subaru Telescope, Gran Telescopio Canarias, and the Gemini telescope were another key to success. “The quasars we discovered will be an interesting subject for further follow-up observations with current and future facilities.”, said Matsuoka. “We will also learn about the formation and early evolution of SMBHs, by comparing the measured number density and luminosity distribution with predictions from theoretical models.” Based on the results achieved so far, the team is looking ahead to search for yet more distant SMBHs, and to reveal the epoch when the first SMBH appeared in the universe.

The research team consists of 48 astronomers around the world. Matsuoka led the team, while Nobunari Kashikawa (The University of Tokyo), Michael Strauss (Princeton University), Masafusa Onoue (Max Planck Institute for Astronomy), Kazushi Iwasawa (Universitat de Barcelona), and Tomotsugu Goto (National Tsing Hua University) have played key roles in the individual steps of the project. The results of the project are presented in the following five papers (paper [2] in particular).



[1] “Discovery of the First Low-luminosity Quasar at z > 7”, Matsuoka et al., The Astrophysical Journal Letters, 872 (2019), 2


[2] “Subaru High-z Exploration of Low-luminosity Quasars (SHELLQs). V. Quasar Luminosity Function and Contribution to Cosmic Reionization at z = 6”, Matsuoka et al. 2018, The Astrophysical Journal, 869 (2018), 150


[3] “Subaru High-z Exploration of Low-luminosity Quasars (SHELLQs). IV. Discovery of 41 Quasars and Luminous Galaxies at 5.7 ≤ z ≤ 6.9”, Matsuoka et al., The Astrophysical Journal Supplement Series, 237 (2018), 5


[4] “Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs). II. Discovery of 32 quasars and luminous galaxies at 5.7 < z ≤ 6.8”, Matsuoka et al., Publications of the Astronomical Society of Japan, 70 (2018), S35


[5] “Subaru High-z Exploration of Low-luminosity Quasars (SHELLQs). I. Discovery of 15 Quasars and Bright Galaxies at 5.7 < z < 6.9”, Matsuoka et al., The Astrophysical Journal, 828 (2016), 26


The HSC collaboration includes the astronomical communities of Japan and Taiwan, and Princeton University. The HSC instrumentation and software were developed by the National Astronomical Observatory of Japan (NAOJ), the Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU), the University of Tokyo, the High Energy Accelerator Research Organization (KEK), the Academia Sinica Institute for Astronomy and Astrophysics in Taiwan (ASIAA), and Princeton University. Funding was contributed by the FIRST program from Japanese Cabinet Office, the Ministry of Education, Culture, Sports, Science and Technology (MEXT), the Japan Society for the Promotion of Science (JSPS), Japan Science and Technology Agency (JST), the Toray Science Foundation, NAOJ, Kavli IPMU, KEK, ASIAA, and Princeton University.






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Housekeeping and Maintenance Punctuate Last Full Day of Expedition 58


ISS – Expedition 58 Mission patch.


March 13, 2019



International Space Station (ISS). Animation Credit: NASA

The last full day of Expedition 58—before the launch, docking and consolidation of crews to become Expedition 59—was mostly spent on housekeeping items for the continued, successful operation of the International Space Station.


NASA astronaut Anne McClain floated through the Tranquility and Zvezda service modules, deploying acoustic monitors. She paused in the U.S. lab at an EXPRESS rack to install communications gear and perform additional maintenance. David Saint-Jacques of the Canadian Space Agency also worked with EXPRESS today, moving Space Automated Bioproduct Labs from rack-1 to rack-2. This miniature laboratory within the larger orbiting laboratory supports life science research, hosting microorganisms (bacteria, yeast, algae, fungi, viruses, etc.), small organisms, animal cells, tissue cultures and small plants for evaluation in space.



Image above: From left, Expedition 59 crew members Christina Koch, Alexey Ovchinin and Nick Hague show solidarity before their upcoming launch from Baikonur, Kazakhstan. Image Credit: NASA.


Expedition Commander Oleg Kononenko of Roscosmos replaced fuel bottles on the Combustion Integrated Rack, which allows the crew members to conduct fluids and combustion studies in microgravity.


Today in Baikonur, Kazakhstan, NASA astronauts Nick Hague and Christina Koch, and cosmonaut Alexey Ovchinin of Roscosmos, were certified for flight by the Russian state commission and held their final news conference.



Image above: Expedition 59 crew members Christina Koch of NASA, Alexey Ovchinin of Roscosmos and Nick Hague of NASA during pre-launch training for launch March 14, U.S. time, on the Soyuz MS-12 spacecraft from the Baikonur Cosmodrome in Kazakhstan for a six-and-a-half month mission on the International Space Station. Image Credit: NASA.


Tomorrow, the soon-to-be station residents will hitch a ride aboard a Soyuz MS-12 for blastoff at 3:14 p.m. EDT on, coincidentally, 3/14. After a relatively speedy six-hour flight, the Soyuz is expected to dock to station’s Rassvet module at 9:07 p.m. Expedition 59 will begin officially at the time of docking.


The events will unfold live on NASA TV, with launch coverage beginning at 2 p.m. and docking coverage at 8:15 p.m., respectively. After a brief break, tune in at 10:30 p.m. for the hatch opening and welcome, which will return the orbiting laboratory’s population to six—including three NASA astronauts. And, just in time for Women’s History Month, this launch marks the fourth Expedition crew with two female astronauts. 


Related links:


NASA Coverage for Next Space Station Crew Launch, Docking:
https://www.nasa.gov/press-release/nasa-coverage-for-next-space-station-crew-launch-docking


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


Tranquility module: https://www.nasa.gov/mission_pages/station/structure/elements/tranquility/


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


EXPRESS rack: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=598


Space Automated Bioproduct Labs: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=1148


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


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


Animation (mentioned), Images (mentioned), Text, Credits: NASA/Catherine Williams.


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Our Planet: 8 Stunning Views of Earth from Space

Swirling clouds, deep blue oceans and textured land- and icescapes are among the many faces of our planet revealed in NASA’s new photo-essay book: Earth. This collection of 69 images captured by satellites tells a story of a 4.5-billion-year-old planet where there is always something new to see. Earth is a beautiful, awe-inspiring place, and it is the only world most of us will ever know. It is your planet. It is NASA’s mission. The book is available now in hardcover and ebook, and online with interactive features.


Here are eight of those breathtaking images for your viewing pleasure. 


Channel Country, Australia


image

These wide floodplains in Queensland, Australia are unique on the planet. Scientists think they are caused by the extreme variation in water and sediment discharges from the rivers. In many years there is no rainfall at all, and the rivers are effectively non-existent. In years of modest rainfall, the main channels will carry some water, sometimes spilling over into narrow water holes known as billabongs.


Every few decades, the floodplain carries extremely high discharges of water. For instance, tropical storms to the north can lead to great water flows that inundate the entire width of the floodplain. On such occasions, the floodplain appears as series of brown and green water surfaces with only tree tops indicating the location of the islands. Such is the case in this image taken from the International Space Station in September 2016.


Grounded in the Caspian, Kazakhstan


image

A wide variety of ice forms in the Caspian Sea, which stretches from Kazakhstan to Iran. Just offshore, a well-developed expanse of consolidated ice appears bright white. Farther offshore, a gray-white field of chunky, hummocked ice has detached and is slowly drifting around a polynya, an area of open water surrounded by sea ice. That darker patch is actually growing young, thin ice and nilas, a term that designates sea ice crust up to 10 centimeters (4 inches) in thickness.


The close-up shows nilas and a white, diamond-shaped piece of ice. It might look like this chunk is on the move, cutting a path through thinner ice. But it’s more likely that the “diamond” was stuck to the sea bottom and the wind pushed ice around it.


Tsauchab River Bed, Namibia


image

The Tsauchab River is a famous landmark for the people of Namibia and tourists. Yet few people have ever seen the river flowing with water. In December 2009, an astronaut on the International Space Station caught this glimpse of the Tsauchab River bed jutting into the sea of red dunes. It ends in a series of light-colored, silty mud holes on the dry lake floor.


Like several other rivers around the Namib Desert, the Tsauchab brings sediment down from the hinterland toward the coastal lowland. This sediment is then blown from the river beds, and over tens of millions of years it has accumulated as the red dunes of the Namib Sand Sea.


Taranaki and Egmont, New Zealand


image

The circular pattern of New Zealand’s Egmont National Park stands out from space as a human fingerprint on the landscape. The park protects the forested and snow-capped slopes around Mount Taranaki (Mount Egmont to British settlers). It was established in 1900, when officials drew a radius of 10 kilometers around the volcanic peak. The colors differentiate the protected forest (dark green) from once-forested pasturelands (light- and brown-green).


Named by the native Maori people, Taranaki stands 2,518 meters (8,260 feet) tall, and it is one of the world’s most symmetric volcanoes. It first became active about 135,000 years ago. By dating lava flows, geologists have figured out that small eruptions occur roughly every 90 years and major eruptions every 500 years. Landsat 8 acquired this image of Taranaki and the park in July 2014.


Storms Stir Up Sediment in Bermuda


image

In October 2014, the eye of Hurricane Gonzalo passed right over Bermuda. In the process, the potent storm stirred up the sediments in the shallow bays and lagoons around the island, spreading a huge mass of sediment across the North Atlantic Ocean. This Landsat 8 image shows the area after Gonzalo passed through.


The suspended sediments were likely a combination of beach sand and carbonate sediments from around the shallows and reefs. Coral reefs can produce large amounts of calcium carbonate, which stays on the reef flats (where there are coralline algae that also produce carbonate) and builds up over time to form islands.


Framing an Iceberg in the South Atlantic Ocean


image

In June 2016, the Suomi NPP satellite captured this image of various cloud formations in the South Atlantic Ocean. Note how low stratus clouds framed a hole over iceberg A-56 as it drifted across the sea.


The exact reason for the hole in the clouds is somewhat of a mystery. It could have formed by chance, although imagery from the days before and after this date suggest something else was at work. It could be that the relatively unobstructed path of the clouds over the ocean surface was interrupted by thermal instability created by the iceberg. In other words, if an obstacle is big enough, it can divert the low-level atmospheric flow of air around it, a phenomenon often caused by islands.


Lofted Over Land in Madagascar


image

Along the muddy Mania River, midday clouds form over the forested land but not the water. In the tropical rainforests of Madagascar, there is ample moisture for cloud formation. Sunlight heats the land all day, warming that moist air and causing it to rise high into the atmosphere until it cools and condenses into water droplets. Clouds generally form where air is ascending (over land in this case), but not where it is descending (over the river). Landsat 8 acquired this image in January 2015.


A Lava Lamp Look at the Atlantic Ocean 


image

Stretching from tropical Florida to the doorstep of Europe, the Gulf Stream carries a lot of heat, salt, and history. This river of water is an important part of the global ocean conveyor belt, moving water and heat from the Equator toward the far North Atlantic. It is one of the strongest currents on Earth and one of the most studied. Its discovery is often attributed to Benjamin Franklin, though sailors likely knew about the current long before they had a name for it.


This image shows a small portion of the Gulf Stream off of South Carolina as it appeared in infrared data collected by the Landsat 8 satellite in April 2013. Colors represent the energy—heat—being emitted by the water, with cooler temperatures in purple and the warmest water being nearly white. Note how the Gulf Stream is not a uniform band but instead has finer streams and pockets of warmer and colder water.


These images are just a few from our new book called Earth. Explore the other 61 images here.


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


Decorated fragments from the 3rd century CE Aesica Hoard found at Great Chesters Roman...

Decorated fragments from the 3rd century CE Aesica Hoard found at Great Chesters Roman Fort, Great North Museum, Hancock, Newcastle upon Tyne, 24.2.19.




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Goddard Technologists and Scientists Prepare for a New Era of Human Exploration


NASA Goddard Space Flight Center logo.


March 13, 2019


NASA scientists, engineers, and technologists are preparing for a new era of human exploration at the Moon, which includes a new launch system, capsule, and lunar-orbiting outpost that will serve as the jumping-off point for human spaceflight deeper into the Solar System.





Image above: Goddard will provide laser communications services to NASA’s Orion vehicle, shown in this artist concept. Image Credit: NASA.


NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is playing a vital role in these initiatives, particularly in the areas of communications and instrument development as evidenced by the recent award of five proposals under NASA’s Development and Advancement of Lunar Instrumentation (DALI) to advance spacecraft-based instrument for use in lunar-landing missions.


The technologies needed for sustainable exploration at the Moon will have to be powerful, multipurpose, and fast, said Jake Bleacher, Chief Scientist for the Human Exploration and Operations Mission Directorate.


Transition to Laser Communications


Goddard’s legacy role of providing communications between the ground and next-generation spacecraft will be the center’s most significant contribution to the exploration of the Moon and Mars with NASA’s Space Launch System, Orion spacecraft, and the Gateway.


“Houston may have broadcast Neil Armstrong’s first words, but they had to first come through Goddard’s communications hub,” said Noah Petro, the project scientist on the Lunar Reconnaissance Orbiter, or LRO, which has thoroughly mapped the lunar surface — data that will inform future Moon landings.



Image above: Apollo 11 Astronaut Buzz Aldrin moves toward a position to deploy two components of the Early Apollo Scientific Experiments Package, or EASEP, on the lunar surface. Image Credit: NASA.


Radio frequency (RF)-based systems have historically consisted of a vast network of ground antennas and land lines, and more recently NASA’s Tracking and Data Relay Satellites, or TDRS. These systems are giving way to optical or laser communications. Although radio-based systems will continue playing a role, laser communications will be able to support the demand for high-definition video and increased data loads.


NASA also plans to add laser communication capabilities on next-generation relay satellites in geosynchronous orbit — similar to the radio-based TDRS constellation —. “We’re working to develop the next-generation of relay satellites that provide optical services,” said Dave Israel, a communications architect for Goddard’s Exploration and Space Communications division.


To demonstrate an operational laser communications system, Goddard is expected to launch the Laser Communications Relay Demonstration, or LCRD, mission aboard a U.S. Air Force spacecraft that will operate 22,000 miles above Earth’s surface in geosynchronous orbit. Over the mission’s lifespan, LCRD will relay data encoded onto beams of infrared light, which is invisible to the human eye, between two Earth terminals in California and Hawaii.


In 2021, NASA is expected to demonstrate the first fully operational end-to-end laser communications system, called ILLUMA-T, on the International Space Station. There, the Goddard-developed technology will serve as a laser communications terminal for the space station, communicating data from low-Earth orbit to the ground through the LCRD relay. This will demonstrate the potential for laser communications at rates that are 10 to 100 times better than radio-frequency systems, using less power and mass.


NASA will later fly crew aboard the Orion spacecraft to travel around the Moon and back with the Goddard-developed Optical to Orion Communications System, or O2O, to provide high-speed data and high-definition video streaming during the mission. After the initial flight, Goddard technologists expect to add more laser communications terminals on future exploration missions, including a terminal on Gateway.


The New Normal: Multipurpose Scientific Instruments


Goddard’s role in human spaceflight is not limited to communications. During the Apollo era, the center developed several instrument packages, and that role will continue in the next era of lunar exploration.



Image above: In this artist’s concept image, the Gateway is shown mid-assembly. The first logistics module carrying cargo and other goods is docked to the spaceship as it orbits the Moon. Image Credit: NASA.


NASA’s Gateway in orbit around the Moon will be an outpost to explore the lunar surface, conduct experiments, and prepare for spaceflights to more distant destinations, and instruments that can be used for multiple purposes will be important to optimizing potential science and exploration.


“Our job is to think of other ways that a science instrument could be used,” Bleacher said.


An example of this multipurpose philosophy is the Goddard-developed Neutron star Interior Composition Explorer, or NICER, as well as a multifunctional sensor platform now under development, Bleacher said.


NICER is designed primarily to study neutron stars, but it also carries built-in software that uses timing data from pulsing neutron stars to stitch together autonomous navigational solutions, similar to how the Global Positioning System, widely known as GPS, provides positioning, navigation, and timing services to users on Earth. This technology, demonstrated in an experiment called Station Explorer for X-ray Timing and Navigation Technology, or SEXTANT, provides a new option for deep space navigation that could work in concert with existing spacecraft-based radio and optical systems.


This year, NICER Principal Investigator Keith Gendreau and his team are expected to showcase yet another potentially groundbreaking technology with the NICER payload — X-ray communications, or XCOM, in space. Although very early in its development, XCOM could usher in the next generation of communications technologies.



Image above: Geologist-Astronaut Harrison Schmitt, Apollo 17 Lunar Module pilot, is photographed next to the American Flag during NASA’s final lunar landing mission in the Apollo series — a mission that included an instrument developed by Goddard scientist Otto Berg. The photo was taken at the Taurus-Littrow landing site. The highest part of the flag appears to point toward planet Earth in the distant background. Image Credit: NASA.


“NICER is the model we want to apply to everything,” Bleacher said. “My goal is to maximize the time of use for any technology we develop. It’s a multipurpose tool and finding all the ways we can use it is where exploration gets interesting.”


NASA is going to the Moon and on to Mars, in a measured, sustainable way. The direction from Space Policy Directive-1 builds on the hard work NASA is doing on its SLS and Orion spacecraft, agency efforts to enable commercial partners, its work with international partners at the International Space Station in low-Earth orbit, and what NASA learns from its current robotic missions at the Moon and Mars.


For more Goddard technology news, go to https://www.nasa.gov/sites/default/files/atoms/files/winter_2019_final_web_version.pdf


Related articles:


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


NASA Set to Demonstrate X-ray Communications in Space
https://orbiterchspacenews.blogspot.com/2019/02/nasa-set-to-demonstrate-x-ray.html


Related links:


NASA’s Development and Advancement of Lunar Instrumentation (DALI): https://www.nasa.gov/feature/goddard/2019/five-teams-win-nasa-dali-awards-to-advance-future-lunar-missions


Moon and Mars: https://www.nasa.gov/topics/moon-to-mars


Optical to Orion Communications System (O2O): https://c/Users/kahamble/AppData/Local/Microsoft/Windows/INetCache/Content.Outlook/69S01WMC/Optical%20to%20Orion


Neutron star Interior Composition Explorer (NICER): https://www.nasa.gov/nicer


Station Explorer for X-ray Timing and Navigation Technology (SEXTANT): https://www.nasa.gov/feature/goddard/2018/nasa-team-first-to-demonstrate-x-ray-navigation-in-space


Space Policy Directive-1: https://www.nasa.gov/press-release/new-space-policy-directive-calls-for-human-expansion-across-solar-system


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


Images (mentioned), Text, Credits: NASA/Lynn Jenner/Goddard Space Flight Center, by Lori Keesey.


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