пятница, 21 декабря 2018 г.

Mystery of coronae around supermassive black holes deepens

Researchers from RIKEN and JAXA have used observations from the ALMA radio observatory located in northern Chile and managed by an international consortium including the National Astronomical Observatory of Japan (NAOJ) to measure, for the first time, the strength of magnetic fields near two supermassive black holes at the centers of an important type of active galaxies. Surprisingly, the strengths of the magnetic fields do not appear sufficient to power the “coronae,” clouds of superheated plasma that are observed around the black holes at the centers of those galaxies.











Mystery of coronae around supermassive black holes deepens
Artist’s conception of the corona around a supermassive black hole [Credt: RIKEN]

It has long been known that the supermassive black holes that lie at the centers of galaxies, sometimes outshining their host galaxies, have coronae of superheated plasma around them, similar to the corona around the Sun. For black holes, these coronae can be heated to a phenomenal temperature of one billion degrees Celsius. It was long assumed that, like that of the Sun, the coronae were heated by magnetic field energies. However, these magnetic fields had never been measured around black holes, leaving uncertainty regarding the exact mechanism.


In a 2014 paper, the research group predicted that electrons in the plasma surrounding the black holes would emit a special kind of light, known as synchrotron radiation, as they exist together with the magnetic forces in the coronae. Specifically, this radiation would be in the radio band, meaning electromagnetic waves with a long wavelength and low frequency. And the group set out to measure these fields.


They decided to look at data from two “nearby,” in astronomical terms, active galactic nuclei: IC 4329A, which is about 200 million light-years away, and NGC 985, which is approximately 580 million light-years away. They began by taking measurements using the ALMA observatory in Chile, and then compared them to observations from two other radio telescopes: the VLA observatory in the United States and the ATCA observatory in Australia, which measure slightly different frequency bands. The team found that indeed there was an excess of radio emission originating from synchrotron radiation, in addition to emissions from the “jets” cast out by the black holes.


Through the observations, the team deduced that the coronae had a size of about 40 Schwarzschild radii, the radius of a black hole from which not even light can escape, and a strength of about 10 gauss, a figure that is a bit more than the magnetic field at the surface of the Earth but quite a bit less than that given out by a typical refrigerator magnet.


“The surprise,” says Yoshiyuki Inoue, the lead author of the paper, published in The Astrophysical Journal, “is that although we confirmed the emission of radio synchrotron radiation from the corona in both objects, it turns out that the magnetic field we measured is much too weak to be able to drive the intense heating of the coronae around these black holes.” He also notes that the same phenomenon was observed in both galaxies, implying that it could be a general phenomenon.


Looking to the future, Inoue says that the group plans to look for signs of powerful gamma rays that should accompany the radio emissions, to further understand what is happening in the environment near supermassive black holes.


Source: RIKEN [December 19, 2018]



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Sapphires and rubies in the sky

21 light years away from us in the constellation Cassiopeia, a planet orbits its star with a year that is just three days long. Its name is HD219134 b. With a mass almost five times that of Earth it is a so-called “super-Earth”. Unlike the Earth however, it most likely does not have a massive core of iron, but is rich in calcium and aluminium.











Sapphires and rubies in the sky
Illustration of one of the exotic super-Earth candidates, 55 Cnc e, which are rich in sapphires and rubies
and might shimmer in blue and red colors [Credit: Thibaut Roger]

“Perhaps it shimmers red to blue like rubies and sapphires, because these gemstones are aluminium oxides which are com-mon on the exoplanet,” says Caroline Dorn, astrophysicist at the Institute for Computational Science of the University of Zurich. HD219134 b is one of three candidates likely to belong to a new, exotic class of exoplanets, as Caroline Dorn and her colleagues at the Universities of Zurich and Cambridge now report in Monthly Notices of the Royal Astronomical Society.
The researchers study the formation of planets using theoretical models and compare their results with data from observations. It is known that during their formation, stars such as the Sun were surrounded by a disc of gas and dust in which planets were born. Rocky planets like the Earth were formed out of the solid bodies leftover when the proto-planetary gas disc dispersed. These building blocks condensed out of the nebula gas as the disc cooled.


“Nor-mally, these building blocks are formed in regions where rock-forming elements such as iron, magnesium and silicon have condensed,” explains Dorn who is associated to the NCCR Plan-etS. The resulting planets have an Earth-like composition with an iron core. Most of the su-per-Earths known so far have been formed in such regions.


The composition of super-Earths is more diverse than expected


But there are also regions close to the star where it is much hotter. “There, many elements are still in the gas phase and the planetary building blocks have a completely different com-position,” says the astrophysicist. With their models, the research team calculated what a planet being formed in such a hot region should look like. Their result: calcium and alumini-um are the main constituents alongside magnesium and silicon, and there is hardly any iron.


“This is why such planets cannot, for example, have a magnetic field like the Earth,” says Dorn. And because the inner structure is so different, their cooling behavior and atmos-pheres will also differ from those of normal super-Earths. The team therefore speak of a new, exotic class of super-Earths formed from high-temperature condensates.


“What is exciting is that these objects are completely different from the majority of Earth-like planets,” says Dorn – “if they actually exist.” The probability is high, as the astrophysi-cists explain in their paper. “In our calculations we found that these planets have 10 to 20 percent lower densities than the Earth,” explains the first author. Other exoplanets with sim-ilarly low-densities were also analyzed by the team.


“We looked at different scenarios to explain the observed densities,” says Dorn. For example, a thick atmosphere could lead to a lower overall density. But two of the exoplanets studied, 55 Cancri e and WASP-47 e, orbit their star so closely that their surface temperature is almost 3000 degrees and they would have lost this gas envelope long ago.


“On HD219134 b it’s less hot and the situation is more complicated,” explains Dorn. At first glance, the lower density could also be explained by deep oceans. But a second planet orbiting the star a little further out makes this scenario unlikely. A comparison of the two objects showed that the inner planet cannot contain more water or gas than the outer one. It is still unclear whether magma oceans can contribute to the lower density.


“So, we have found three candidates that belong to a new class of super-Earths with this exotic composition” the astrophysicist summarizes. The researchers are also correcting an earlier image of super-Earth 55 Cancri e, which had made headlines in 2012 as the “diamond in the sky”. Researchers had previously assumed that the planet consisted largely of carbon, but had to abandon this theory on the basis of subsequent observations. “We are turning the supposed diamond planet into a sapphire planet,” laughs Dorn.


Source: University of Zurich [December 19, 2018]




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Longer growing seasons complicate outlook for coniferous forests

For decades, ecologists have differed over a longstanding mystery: Will a longer, climate-induced growing season ultimately help coniferous forests to grow or hurt them? A new University of Colorado Boulder study may help researchers find a more definitive answer.











Longer growing seasons complicate outlook for coniferous forests
Credit: University of Colorado at Boulder

As climate warming has lengthened growing seasons, two scenarios seem plausible: If forest growth increases as a result of milder temperatures during more of the year, the additional tree cover could help remove carbon dioxide emissions from the atmosphere at a faster rate. Conversely, if growth decreases as a result of decreased moisture or increased heat-related stress, carbon absorption would decline and climate warming could accelerate even beyond current levels.


Despite a large number of studies on the topic, no standard for measuring the beginning, middle and end of a growing season has emerged, leading to diverging — and at times, wildly opposite — conclusions.


“Nobody can say for certain what a growing season ‘is,’ due to all the variation in how forest behave and how the start and end of the growing season is characterized,” said David Barnard, lead author of the study and a former postdoctoral researcher with the Boulder Creek Critical Zone Observatory at the Institute of Arctic and Alpine Research (INSTAAR). “Even in winter, forests in warmer areas can still be growing. There’s less of a distinct on/off switch.”


The new CU Boulder study, published in the journal Scientific Reports, examined data from eleven western sites in the AmeriFlux and Long-Term Ecological Research networks, a set of monitoring stations supported by the Department of Energy and National Science Foundation. These long-term research sites measure, among other things, the exchange of carbon dioxide between forests and the atmosphere.


“I’ve been thinking about this question since grad school when I was working on Niwot Ridge and couldn’t find standard guidelines for how to calculate growing season length,” said John Knowles, co-lead author of the study and a former CU Boulder graduate student now a researcher at the University of Arizona.


By applying different methods for characterizing growing season length to past studies, the researchers found that many previous datasets could be made to yield a positive (forest growth) or negative (forest decline) outlook depending on which single methodology was applied — an ambiguity that complicates efforts to quantify climate change effects at scales ranging from individual forests to continents and the globe.


“This work shows how the result of any given study may be subject to methodological bias, especially in colder, more northerly ecosystems where climate is changing the fastest,” added Barnard, now a researcher with the U.S. Geological Survey.


The study provides recommendations and best practices for calculating growing season length by using an ensemble approach, combining multiple study methods and taking an average to come up with a more robust conclusion.


“It may still be years before it’s clear whether a longer growing season is good, bad or somewhere in-between for forests,” Barnard said.


Notwithstanding, Knowles adds that this work “will immediately help to the characterize the uncertainty associated with how longer growing seasons are likely to impact forest carbon emissions in the future.”


“Every forest behaves differently,” Barnard said. “There is still a good bit of uncertainty about what increasing growing seasons will do for forest growth, but we do know that they are crucial to understanding the global carbon cycle.”


Author: Trent Knoss | Source: University of Colorado at Boulder [December 19, 2018]



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Map of neuronal pathways of the mammalian cerebral cortex and their evolution

The cerebrum plays the most important roles in the higher functions of the brain. In particular, the cerebral cortex, among other parts of the cerebrum, is essential. Humans have by far the most developed cerebral cortex among animals and it is thought that we have acquired specific abilities thanks to this. In addition, the cerebral cortex has received special attention, since various parts are involved in various brain diseases, psychiatric disorders and others.











Map of neuronal pathways of the mammalian cerebral cortex and their evolution
Fig. 1: Upper left panel. A cross-sectional image of the ferret brain. Some neurons of the cerebral cortex (blue) are dyed
green with GFP, green fluorescent protein. Upper right panel. The rectangle with white edges of the upper left panel is
enlarged. It is found that there are two axonal fiber layers (green bundles) in the cerebral cortices. Lower panel. The fiber
layer on the surface side (green, indicated by an arrow), i.e., the outer fiber layer, has destinations in the proximal areas
of the same cerebral cortex, while the deep fiber layer (green, indicated by arrowheads), i.e. the inner fiber layer,
has destinations in the opposite cerebral cortex and other brain regions. Thus, the two axonal fiber layers
have different destinations [Credit: Kanazawa University]

The developing cerebral cortex of higher animals like humans contains two axonal fiber layers that transmit neural information and are, therefore, considered to be important in brain functions. The cerebral cortex of the mouse, the most commonly used model animal in research, was not found to have equivalents of the axonal fiber layers, which made mouse research on this subject very difficult. Thus, research on these fiber layers has been much retarded.
The present research group at Kanazawa University has been promoting studies using the ferret, since it is important to conduct research using higher animals with a more developed cerebrum, closer to that of the human than the mouse. Research techniques for the ferret were previously not available, so in 2012 and 2013 the group developed an appropriate technique, in utero electroporation, for use in ferrets at the gene level. They have thus led research into the brains of higher mammals including the development of disease model ferrets in 2015 and 2017.











Map of neuronal pathways of the mammalian cerebral cortex and their evolution
Fig. 2: A cross-sectional image of the mouse cerebral cortex in enlargement. The same method was applied as in the ferret.
The cerebral cortex is shown in blue and some neurons are dyed green with GFP. In addition to the deep axonal fiber
layer (green, indicated by an arrowhead), a small number of axonal bundles (green, indicated by an arrow) are found.
It is considered that in the ferret, these bundles have evolved to be more robust to become the axonal
fiber layer on the surface side [Credit: Kanazawa University]

In the present study, the Kanazawa University group has mapped the fiber layers of the developing cerebrum of a higher mammal, the ferret, using its own unique research technique. They have also found an important clue to the evolution of these fiber layers. More specifically, the following three points have been established:


1. The two axonal fiber layers found in the human and monkey brain also exist in the ferret brain.


By introducing GFP (green fluorescent protein) into neurons in the ferret cerebral cortex, it was found that axons in two fiber layers are derived from the neurons of the cerebral cortex (Figure 1 upper right panel, indicated with [ symbols).


2. The two axonal fiber layers have different destinations in the brain.


Upon investigation of the destinations of the two fiber layers, the one on the surface side of the cerebral cortex has destinations in the proximal areas of the cerebral cortex; i.e. it represents a short-distance pathway (Figure 1 lower panel, indicated with an arrow); on the other hand, the other in the deep side of the cerebral cortex has destinations in the cerebral cortex of the opposite hemisphere and to the other brain regions; i.e. it represents a long-distance pathway (Figure 1 lower panel, indicated by arrowheads). Thus, selection of the axonal fiber layers takes place depending on their destination.











Map of neuronal pathways of the mammalian cerebral cortex and their evolution
Fig. 3: The trace-like axonal fiber bundles are now considered to have become more robust during the evolution of ferrets
 or humans and, as a result, the second axonal fiber layer has been formed. The destinations of the two axonal
fiber layers are also found to be different [Credit: Kanazawa University]

3. A trace of axonal fiber bundles is found in the mouse brain.


So far, equivalents of the two fiber layers were not described in the mouse cerebral cortex. The group applied the same technique, used to reveal the two fiber layers in the ferret brain, to the mouse brain. Unexpectedly, they found one fiber layer (Figure 2, indicated by an arrowhead) as well as a trace of axonal fiber bundles (Figure 2, indicated by an arrow). This trace pathway is thought to have later evolved to become the second axonal fiber layer of higher mammals (Figure 3). This raises the possibility that it is this second axonal fiber layer, i.e. the outer fiber layer, which is important in the development of higher brain functions.


In this study, the Kanazawa University group has elucidated the destinations of the two axonal fiber layers in the cerebrum and the process of their evolution with the use of their unique research technique for the ferret. This finding is of major significance, since there have been very few studies on these two fiber layers. This study should contribute to our understanding of brain evolution in higher organisms up to the human, which has been very difficult with the mouse, a conventional model animal. Further, it should help reveal causes of various brain disorders.


Source: Kanazawa University [December 19, 2018]



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Stick insects: Egg-laying techniques reveal new evolutionary map

Known for exceptional mimicry, stick insects have evolved a range of egg-laying techniques to maximize egg survival while maintaining their disguise — including dropping eggs to the ground, skewering them on leaves, and even enlisting ants for egg dispersal. Scientists have now combined knowledge on these varied techniques with DNA analysis to create the best map of stick-insect evolution to date.











Stick insects: Egg-laying techniques reveal new evolutionary map
Credit: iStockphoto

Contrary to previous evolutionary theories based on anatomical similarities, the new analysis finds the first stick insects flicked or dropped their eggs while hiding in the foliage. It also finds that geographically isolated populations of stick insects are more likely to be related than those with similar features. The research, published in a special issue on stick insects in Frontiers in Ecology and Evolution, takes us one step closer to understanding these enigmatic creatures.


“While the evolutionary history of most insect groups is well documented, stick insects have been hard to classify. Our new analysis has made great strides, showing that the evolution of stick and leaf insects cannot be solely based on anatomical features,” says Dr James A. Robertson, based at the Animal and Plant Health Inspection Service and affiliated with the Brigham Young University, USA. “Linking their wide-variety of egg-laying techniques to their evolutionary history, we find that flicking and dropping eggs is the oldest strategy from an evolutionary perspective.”


Stick insects are increasingly popular in the pet industry on account of their remarkable size, bizarre appearance and gentle nature. They are the only insects where each species has an individual egg form. In the 1950s, scientists based stick-insect evolutionary theories on the traditional method of examining subtle changes in anatomical features. However, this method could not explain why distantly-related species — for example those separated by faraway continents — often shared very similar features.


Using DNA analysis and linking these findings to their variety of egg-laying techniques, Robertson and his colleagues created their own map of stick-insect evolution. As well as revealing that species geographically isolated with each other were more likely to be related than species that looked similar, the results challenged previous theories on how stick-insect egg-laying strategies evolved.


“Stick-insects were thought to evolve from a ground-dwelling adult form that deposited its eggs directly in the soil. We show that ancestral stick-insects actually remained in the foliage and dropped or flicked their eggs to the ground, a technique employed by most of these insects as a strategy to remain in disguise,” explains Robertson. “The hardening of the egg capsule early in the evolution of stick insects represents a key innovation allowing further diversification.”


This hardened capsule allows the egg to survive falls from the canopy, to float on water and to pass through the intestines of birds. A further innovation, exclusive to stick insects that flick or drop their eggs, is a food-filled cap on the egg that attracts ants, who then disperse it much further than a female stick insect could achieve on her own.


Robertson continues, “Stick insects have then adapted to new micro-habitats, which involves changing how their eggs are deployed and dispersed. There are several independent examples where species have evolved to adapt to a ground or bark dwelling habitat by depositing their eggs in the soil or in bark crevasses. Other populations have independently evolved gluing strategies, with one of these diversifying further by burying their eggs, skewering them in leaves or producing a sophisticated egg sac.”


This new research demonstrates that molecular data can begin to shed light on the evolution of these enigmatic creatures, with more to be revealed.


Robertson explains, “We hope to investigate how and when key innovations in stick insect evolution occurred, how widespread these traits are and where geographically they evolved.”


Source: Frontiers [December 19, 2018]



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Study finds dinosaurs battled overheating with nasal air-conditioning

Researchers have long wondered how gigantic, heavily armored dinosaurs, such as the club-tailed ankylosaurs that lived in sweltering climates, avoided overheating. While their large bodies were adept at retaining heat, their sheer size created a heat-shedding problem that would have put them at risk of overheating, even on cloudy days. In the absence of a protective cooling mechanism, the delicate neural tissue of their brains could be damaged by the hot blood from the core of their bodies.











Study finds dinosaurs battled overheating with nasal air-conditioning
Panoplosaurus mirus and Euoplocephalus tutus [Credit: Bourke et al, 2018]

Now researchers, led by a paleontologist from New York Institute of Technology College of Osteopathic Medicine at Arkansas State University (NYITCOM at A-State), have posed a new theory–the dinosaurs had an intricate cooling system in their snouts.


“The large bodies of many dinosaurs must have gotten very hot in warm Mesozoic climates, and we’d expect their brains to adapt poorly to these conditions. With that in mind, we wanted to see if there were ways to protect the brain from ‘cooking.’ It turns out the nose may be the key, and likely housed a ‘built-in air conditioner,'” said Jason Bourke, Ph.D., assistant professor of basic sciences, NYITCOM at A-State, and lead author of the study.


According to the researchers, smell may be a primary function of the nose, but noses are also important heat exchangers, ensuring that air is warmed and humidified before it reaches the delicate lungs. To accomplish this effective air conditioning, birds and mammals–including humans–rely on thin curls of bone and cartilage within their nasal cavities, called turbinates, which increase the surface area and allow for air to come into greater contact with the nasal walls.











Study finds dinosaurs battled overheating with nasal air-conditioning
This is a model of heat exchange in an ankylosaurian dinosaur
[Credit: Jason Bourke, Ph.D., NYITCOM]

The team used Computed Tomography (CT) scanning and a powerful engineering modeling approach called computational fluid dynamics to simulate how air moved through the nasal passages of two different ankylosaur species, the hippo-sized Panoplosaurus and larger rhino-sized Euoplocephalus. These tests examined how well ankylosaur noses transferred heat from the body to the inhaled air. The researchers found that ankylosaurs lacked turbinates, and instead evolved to have longer, coiled noses. Despite this strange anatomy, these noses were just as efficient at warming and cooling respired air.


“A decade ago, my colleague and I published the discovery that ankylosaurs had extremely long nasal passages coiled up in their snouts,” said study co-author Lawrence Witmer, professor of anatomy, Ohio University Heritage College of Osteopathic Medicine. “These convoluted airways resembled a child’s ‘crazy-straw’–completely unexpected and seemingly without reason, until now.”


In Panoplosaurus, the nasal passages were a bit longer than the skull itself, and in Euoplocephalus they were almost twice as long as the skull, as well as coiled up the snout. To see if nasal passage length was the reason for this efficiency, Bourke ran alternative models with shorter, simpler nasal passages that ran directly from the nostril to the throat, as in most other animals. The results clearly showed that nose length was indeed the key to their air-conditioning ability.











Study finds dinosaurs battled overheating with nasal air-conditioning
This is nasal air-conditioning in Euoplocephalus [Credit: Jason Bourke, Ph.D., NYITCOM]

“When we stuck a short, simple nose in their snouts, heat-transfer rates dropped by over 50% in both dinosaurs. They were less efficient and didn’t work very well,” said Bourke.


Another line of evidence that these noses were air conditioners that helped cool the brain came from analyses of blood flow. When blood vessels were reconstructed, based on bony grooves and canals, the team found a rich blood supply running right next to these convoluted nasal passages. According to Ruger Porter, lecturer at the Ohio University Heritage College of Osteopathic Medicine and another of the study’s co-authors, hot blood from the body core would travel through these blood vessels and transfer their heat to the incoming air. Simultaneously, evaporation of moisture in the long nasal passages cooled the venous blood destined for the brain.


The complicated nasal airways of these dinosaurs were acting as radiators to cool down the brain with a constant flow of cooled venous blood, allowing them to keep a cool head at all times. This natural engineering feat also may have allowed the evolution of the great sizes of so many dinosaurs.


“This project is an excellent example of how advances in CT scanning, 3-D reconstruction, imaging, and computational fluid dynamics modeling can be used in biological research to test long-standing hypotheses,” said Kathy Dickson, a program officer at the National Science Foundation (NSF) that funded the research. “From these new images and models, fossils can provide further insight into extinct organisms like the ankylosaur – in this case, offering an explanation of how unusual features actually function physiologically.”


The findings are published in PLOS ONE.


Source: New York Institute of Technology [December 19, 2018]



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Joyriding Viruses When entering a human cell, some viruses…


Joyriding Viruses


When entering a human cell, some viruses just replicate and move on. Others, it appears, grab the steering wheel, start the engine, and make off. This video shows the tracks taken by human cells hijacked by such a virus (infection at the centre). It’s thought that by commandeering the cell’s motility machinery, poxviruses and others like them are able to promote their own spread around the body. Researchers have now discovered that in the case of vaccinia virus (a type of poxvirus) production of a viral protein called vaccinia growth factor (VGF) is responsible for revving the cell’s engine. Indeed, deletion of VGF from the vaccinia genome reduced the spread of the virus and the size of viral lesions in vaccinia-infected mice. By determining the mechanisms underlying this viral joy-riding, researchers hope to develop targeted anti-viral strategies that stop the stolen cells in their tracks and thus reduce the severity of infection.


Written by Ruth Williams



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The Coolest Experiment in the Universe


ISS – International Space Station logo.


December 21, 2018



Image above: The International Space Station, shown here in 2018, is home to many scientific experiments, including NASA’s Cold Atom Laboratory. Image Credit: NASA.


What’s the coldest place you can think of? Temperatures on a winter day in Antarctica dip as low as -120ºF (-85ºC). On the dark side of the Moon, they hit -280ºF (-173ºC). But inside NASA’s Cold Atom Laboratory on the International Space Station, scientists are creating something even colder.


The Cold Atom Lab (CAL) is the first facility in orbit to produce clouds of “ultracold” atoms, which can reach a fraction of a degree above absolute zero: -459ºF (-273ºC), the absolute coldest temperature that matter can reach. Nothing in nature is known to hit the temperatures achieved in laboratories like CAL, which means the orbiting facility is regularly the coldest known spot in the universe.



What’s So Cool About NASA’s Cold Atom Lab?

NASA’s Cold Atom Laboratory on the International Space Station is regularly the coldest known spot in the universe. But why are scientists producing clouds of atoms a fraction of a degree above absolute zero? And why do they need to do it in space? Quantum physics, of course.


Seven months after its May 21, 2018, launch to the space station from NASA’s Wallops Flight Facility in Virginia, CAL is producing ultracold atoms daily. Five teams of scientists will carry out experiments on CAL during its first year, and three experiments are already underway.



Image above: The Cold Atom Laboratory (CAL) consists of two standardized containers that will be installed on the International Space Station. The larger container holds CAL’s physics package, or the compartment where CAL will produce clouds of ultracold atoms. Image Credit: NASA/JPL-Caltech.


Why cool atoms to such an extreme low? Room-temperature atoms typically zip around like hyperactive hummingbirds, but ultracold atoms move much slower than even a snail. Specifics vary, but ultracold atoms can be more than 200,000 times slower than room-temperature atoms. This opens up new ways to study atoms as well as new ways to use them for investigations of other physical phenomena. CAL’s primary science objective is to conduct fundamental physics research – to try to understand the workings of nature at the most fundamental levels.


“With CAL we’re starting to get a really thorough understanding of how the atoms behave in microgravity, how to manipulate them, how the system is different than the ones we use on Earth,” said Rob Thompson, a cold atom physicist at NASA’s Jet Propulsion Laboratory in Pasadena, California, and the mission scientist for CAL. “This is all knowledge that is going to build a foundation for what I hope is a long future of cold atom science in space.”



Image above: The Cold Atom Laboratory (CAL), packaged in a protective layer, is loaded onto a Northrop Grumman (formerly Orbital ATK) Cygnus spacecraft for its trip to the International Space Station. The facility launched in May 2018 from NASA’s Wallops Flight Facility in Virginia. Image Credits: NASA/Northrop Grumman.


Laboratories on Earth can produce ultracold atoms, but on the ground, gravity pulls on the chilled atom clouds and they fall quickly, giving scientists only fractions of a second to observe them. Magnetic fields can be used to “trap” the atoms and hold them still, but that restricts their natural movement. In microgravity, the cold atom clouds float for much longer, giving scientists an extended view of their behavior.


The process to create the cold atom clouds starts with lasers that begin to lower the temperature by slowing the atoms down. Radio waves cut away the warmest members of the group, further lowering the average temperature. Finally, the atoms are released from a magnetic trap and allowed to expand. This causes a drop in pressure that, in turn, naturally causes another drop in the cloud’s temperature (the same phenomenon that causes a can of compressed air to feel cold after use). In space, the cloud has longer to expand and thus reach even lower temperatures than what can be achieved on Earth – down to about one ten billionth of a degree above absolute zero, perhaps even lower.



Image above: Astronaut Ricky Arnold assists with the installation of NASA’s Cold Atom Laboratory (CAL) on the International Space Station. Image Credits: NASA/JPL-Caltech.


Ultracold atom facilities on Earth typically occupy an entire room, and in most, the hardware is left exposed so that scientists can adjust the apparatus if need be. Building a cold atom laboratory for space posed several design challenges, some of which change the fundamental nature of these facilities. First, there was the matter of size: CAL flew to the station in two pieces – a metal box a little larger than a minifridge and a second one about the size of a carry-on suitcase. Second, CAL was designed to be operated remotely from Earth, so it was built as a fully enclosed facility.


CAL also features a number of technologies that have never been flown in space before, such as specialized vacuum cells that contain the atoms, which have to be sealed so tightly that almost no stray atoms can leak in. The lab needed to be able to withstand the shaking of launch and extreme forces experienced during the flight to the space station. It took the teams several years to develop unique hardware that could meet the precise needs for cooling atoms in space.



Image above: Cold Atom Laboratory (CAL) physicist David Aveline works in the CAL test bed, which is a replica of the CAL facility that stays on Earth. Scientists use the test bed to run tests and understand what is happening inside CAL while it is operating on the International Space Station. Image Credits: NASA/JPL-Caltech.


“Several parts of the system required redesigning, and some parts broke in ways we’d never seen before,” said Robert Shotwell, chief engineer for JPL’s Astronomy, Physics and Space Technology Directorate and CAL project manager. “The facility had to be completely torn apart and reassembled three times.”


All the hard work and problem solving since the mission’s inception in 2012 turned the CAL team’s vision into reality this past May. CAL team members talked via live video with astronauts Ricky Arnold and Drew Feustel aboard the International Space Station for the installation of the Cold Atom Laboratory, the second ultracold atom facility ever operated in space, the first to reach Earth orbit and the first to remain in space for more than a few minutes. Along the way, CAL has also met the minimum requirements NASA set to deem the mission a success and is providing a unique tool for probing nature’s mysteries.



Image above: Shown here is the “physics package” inside the Cold Atom Laboratory (CAL), where ultracold clouds of atoms called Bose-Einstein condensates are produced. Image Credits: NASA/JPL-Caltech.


Designed and built at JPL, CAL is sponsored by the International Space Station Program at NASA’s Johnson Space Center in Houston, and the Space Life and Physical Sciences Research and Applications (SLPSRA) Division of NASA’s Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington.


Related links:


Cold Atom Laboratory (CAL):
https://www.jpl.nasa.gov/spaceimages/index.php?search=Cold+Atom+Laboratory+%28CAL%29


More information on CAL is online at: http://coldatomlab.jpl.nasa.gov.


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


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Hubble’s Cosmic Holiday Wreath


NASA – Hubble Space Telescope patch.


Dec. 21, 2018



This festive NASA Hubble Space Telescope image resembles a holiday wreath made of sparkling lights. The bright southern hemisphere star RS Puppis, at the center of the image, is swaddled in a gossamer cocoon of reflective dust illuminated by the glittering star. The super star is ten times more massive than the Sun and 200 times larger.


RS Puppis rhythmically brightens and dims over a six-week cycle. It is one of the most luminous in the class of so-called Cepheid variable stars. Its average intrinsic brightness is 15,000 times greater than the Sun’s luminosity.


The nebula flickers in brightness as pulses of light from the Cepheid propagate outwards. Hubble took a series of photos of light flashes rippling across the nebula in a phenomenon known as a “light echo.” Even though light travels through space fast enough to span the gap between Earth and the Moon in a little over a second, the nebula is so large that reflected light can actually be photographed traversing the nebula.


By observing the fluctuation of light in RS Puppis itself, as well as recording the faint reflections of light pulses moving across the nebula, astronomers are able to measure these light echoes and pin down a very accurate distance. The distance to RS Puppis has been narrowed down to 6,500 light-years (with a margin of error of only one percent).



Hubble Space Telescope (HST)

For more information about Hubble, visit:


http://hubblesite.org/


http://www.nasa.gov/hubble


http://www.spacetelescope.org/


Image, Animation, Credits: NASA, ESA and the Hubble Heritage Team (STScI/AURA) – Hubble/Europe Collaboration; Acknowledgement: H. Bond (STScI and Pennsylvania State University)/Text Credits: Space Telescope Science Institute (STScI)/NASA/Karl Hille.


Season’s Greetings, Orbiter.chArchive link


International Crew to Ring in Christmas 50 Years After First Moon Trip


ISS – Expedition 58 Mission patch.


December 21, 2018


Three people from the U.S., Canada and Russia are orbiting Earth today getting ready to observe Christmas and experience New Year’s Eve from space aboard the International Space Station. Back on Earth, another three station crew members have returned to their home bases just 24 hours after completing a 197-day mission aboard the orbital lab.



Image above: The official Expedition crew portrait with (from left) NASA astronaut Anne McClain, Roscosmos cosmonaut Oleg Kononenko and astronaut David Saint-Jacques of the Canadian Space Agency. Image Credit: NASA.


The first time three humans spent Christmas in space was 50 years ago in 1968 during Apollo 8 and was also the first time a crew orbited the Moon. This Christmas astronauts Anne McClain of NASA and David Saint-Jacques of the Canadian Space Agency with cosmonaut Oleg Kononenko of Roscosmos will be soaring about 250 miles above the Earth’s surface in a much larger spacecraft. The Expedition 58 trio will share a traditional meal aboard the orbital lab, share gifts and call down to family during their off-duty day.


Kononenko is beginning his fourth mission on the station and will spend his second Christmas in space. McClain and Saint-Jacques are getting used to life in space for the first time and will return to Earth in June with Kononenko.



International Space Station (ISS). Image Credit: NASA

NASA astronaut Serena Auñón-Chancellor returned to Houston late Thursday just one day after landing in Kazakhstan wrapping up her six-and-a-half month stay aboard the orbital lab. She parachuted to Earth inside the Soyuz MS-09 spacecraft with her Expedition 57 crewmates Alexander Gerst of ESA (European Space Agency) and Sergey Prokopyev of Roscosmos.


Related article:


A Bold Step: Apollo 8 Sends First Human Flight Beyond Earth
https://orbiterchspacenews.blogspot.com/2018/12/a-bold-step-apollo-8-sends-first-human.html


Related links:


Expedition 57: https://www.nasa.gov/mission_pages/station/expeditions/expedition57/index.html


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


Apollo 8: https://www.nasa.gov/mission_pages/apollo/apollo-8.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


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


Best regards, Orbiter.chArchive link


2018 December 21 Extraordinary Solar Halos Image Credit &…


2018 December 21


Extraordinary Solar Halos
Image Credit & Copyright: Magnus Edback


Explanation: Welcome to the December Solstice, the first day of winter in planet Earth’s northern hemisphere and summer in the south. To celebrate, consider this extraordinary display of beautiful solar ice halos! More common than rainbows, simple ice halos can be easy to spot, especially if you can shade your eyes from direct sunlight. Still it’s extremely rare to see anything close to the complex of halos present in this astounding scene. Captured at lunchtime on a cold December 14 near Utendal, Sweden the image includes the relatively ordinary 22 degree halo, sundogs (parhelia) and sun pillars. The extensive array of rarer halos has been identified along with previously unknown features. All the patterns are generated as sunlight (or moonlight) is reflected and refracted in flat six-sided water ice crystals in Earth’s atmosphere. In this case, likely local contributors to the atmospheric ice crystals are snow making machines operating at at nearby ski center.


∞ Source: apod.nasa.gov/apod/ap181221.html


HiPOD (20 December 2018): Flows Northwest of Elysium Mons    –…



HiPOD (20 December 2018): Flows Northwest of Elysium Mons 


   – Elysium Mons is flanked by the smaller volcanoes Hecates Tholus to the northeast, and Albor Tholus to the southeast. (Alt: 293 km. Black and white is less than 5 km across; enhanced color is less than 1 km.)


NASA/JPL/University of Arizona


Expedition 57 Trio Back on Earth After 197-Day Space Mission


ROSCOSMOS – Soyuz MS-09 Mission patch.


December 20, 2018



Image above: Expedition 57 crew members Sergey Prokopyev of the Russian space agency Roscosmos, Serena Auñón-Chancellor of NASA, and Alexander Gerst of ESA (European Space Agency) emerge one at a time from the Soyuz MS-09 that carried them home from the International Space Station Dec. 20, 2018, after a 197-day mission. The spacecraft touched down in Kazakhstan at 12:02 a.m. EST, marking the end of a voyage that took them around the globe 3,152 times, covering 83.3 million miles. Image Credits: NASA Television.


Three members of the International Space Station’s Expedition 57 crew, including NASA astronaut Serena Auñón-Chancellor, returned to Earth Thursday, safely landing at 12:02 a.m. EST (11:02 a.m. local time) in Kazakhstan.



Soyuz MS-09 landing

Auñón-Chancellor and her crewmates, Expedition 57 Commander Alexander Gerst of ESA (European Space Agency) and Soyuz commander Sergey Prokopyev, launched June 6 and arrived at the space station two days later to begin their mission.


The Expedition 57 crew contributed to hundreds of experiments in biology, biotechnology, physical science and Earth science aboard the world-class orbiting laboratory. Highlights included investigations into new cancer treatment methods and algae growth in space. The crew also installed a new Life Sciences Glovebox, a sealed work area for life science and technology investigations that can accommodate two astronauts.



Image above: Official crew portrait of Expedition 57 crew members (from left) Serena Auñón-Chancellor of NASA, Alexander Gerst of ESA (European Space Agency) and Sergey Prokopyev of Roscosmos. Image Credit: NASA.


During the 197 days, they circled the globe 3,152 times, covering 83.3 million miles. This was the first flight for Auñón-Chancellor and Prokopyev and the second for Gerst, who – with a total of 362 days in orbit – now holds the flight duration record among ESA astronauts.


For the last 16 days of her mission, Auñón-Chancellor was joined by fellow NASA astronaut Anne McClain, marking the first time in which the only two U.S. astronauts on a mission were both women.


Prokopyev completed two spacewalks totaling 15 hours and 31 minutes. He and Oleg Artemyev of Roscosmos launched four small technology satellites and installed an experiment during a spacewalk Aug. 15. Then during a 7 hour, 45 minute spacewalk Dec. 11, he and Oleg Kononenko of Roscosmos retrieved patch samples and took digital images of a repair made to the habitation module of the Soyuz MS-09 in which the Expedition 57 trio rode home. The space station crew located and, within hours of its detection, repaired a small hole inside the Soyuz in August. The spacecraft was thoroughly checked and deemed safe for return to Earth.



Image above: The Soyuz MS-09 crew spacecraft from Roscosmos undocking to the Rassvet module. Image Credits: NASA TV/ISS HD Live/Orbiter.ch Aerospace/Roland Berga.


Auñón-Chancellor will return home to Houston, Gerst will return to Cologne, Germany, and Prokopyev will return to Star City, Russia, following post-landing medical checks and research activities.


The Expedition 58 crew continues operating the station, with Oleg Kononenko of Roscosmos in command. Along with his crewmates Anne McClain of NASA and David Saint-Jacques of the Canadian Space Agency, the three-person crew will operate the station for a little more than two months until three additional crew members launch Feb. 28, 2019 to join them.


Related article:


Expedition 57 Crew Departs Station, Begins Ride Back to Earth
https://orbiterchspacenews.blogspot.com/2018/12/expedition-57-crew-departs-station.html


Related links:


Expedition 57: https://www.nasa.gov/mission_pages/station/expeditions/expedition57/index.html


New cancer treatment methods: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7502


Algae growth in space: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7446


Life Sciences Glovebox: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=7676


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


Images (mentioned), Video, Text, Credits: NASA/Mark Garcia/NASA TV/SciNews/Orbiter.ch Aerospace/Roland Berga.


Best regards, Orbiter.chArchive link


Faint Glow Within Galaxy Clusters Illuminates Dark Matter


NASA – Hubble Space Telescope patch.


Dec. 20, 2018


A new look at Hubble images of galaxies could be a step toward illuminating the elusive nature of dark matter, the unobservable material that makes up the majority of the universe, according to a study published online today in the Monthly Notices of the Royal Astronomical Society.


Utilizing Hubble’s past observations of six massive galaxy clusters in the Frontier Fields program, astronomers demonstrated that intracluster light — the diffuse glow between galaxies in a cluster — traces the path of dark matter, illuminating its distribution more accurately than existing methods that observe X-ray light.



Image above: Hubble’s powerful sensitivity and resolution captures a soft blue haze, called intracluster light, among innumerable galaxies in the Abell S1063 cluster. The stars producing this glow have been thrown out from their galaxies. These stars now live solitary lives, no longer part of a galaxy but aligning themselves with the gravity of the overall cluster. Astronomers have found that intracluster light’s association with a map of mass distribution in the cluster’s overall gravitational field makes it a good indicator of how invisible dark matter is distributed in the cluster. Image Credits: NASA, ESA and M. Montes (University of New South Wales).


Intracluster light is the byproduct of interactions between galaxies that disrupt their structures; in the chaos, individual stars are thrown free of their gravitational moorings in their home galaxy to realign themselves with the gravity map of the overall cluster. This is also where the vast majority of dark matter resides. X-ray light indicates where groups of galaxies are colliding, but not the underlying structure of the cluster. This makes it a less precise tracer of dark matter.


“The reason that intracluster light is such an excellent tracer of dark matter in a galaxy cluster is that both the dark matter and these stars forming the intracluster light are free-floating on the gravitational potential of the cluster itself — so they are following exactly the same gravity,” said Mireia Montes of the University of New South Wales in Sydney, Australia, who is co-author of the study. “We have found a new way to see the location where the dark matter should be, because you are tracing exactly the same gravitational potential. We can illuminate, with a very faint glow, the position of dark matter.”


Montes also highlights that not only is the method accurate, but it is more efficient in that it utilizes only deep imaging, rather than the more complex, time-intensive techniques of spectroscopy. This means more clusters and objects in space can be studied in less time — meaning more potential evidence of what dark matter consists of and how it behaves.


“This method puts us in the position to characterize, in a statistical way, the ultimate nature of dark matter,” Montes said.



Image above: Amid the bright light of its member galaxies, the galaxy cluster MACS J0416.1-2403 also emits a soft glow of intracluster light, produced by stars that are not part of any individual galaxy. These stars were scattered throughout the cluster long ago, when their home galaxies were torn apart by the cluster’s gravitational forces. The homeless stars eventually aligned themselves with the gravity of the overall cluster. Hubble’s unique sensitivity and resolution captures the faint light and uses it to trace the location of invisible dark matter, which dominates the cluster’s gravitational field. Image Credits: NASA, ESA and M. Montes (University of New South Wales).


“The idea for the study was sparked while looking at the pristine Hubble Frontier Field images,” said study co-author Ignacio Trujillo of the Canary Islands Institute of Astronomy in Tenerife, Spain, who along with Montes had studied intracluster light for years. “The Hubble Frontier Fields showed intracluster light in unprecedented clarity. The images were inspiring,” Trujillo said. “Still, I did not expect the results to be so precise. The implications for future space-based research are very exciting.”


“The astronomers used the Modified Hausdorff Distance (MHD), a metric used in shape matching, to measure the similarities between the contours of the intracluster light and the contours of the different mass maps of the clusters, which are provided as part of the data from the Hubble Frontier Fields project, housed in the Mikulski Archive for Space Telescopes (MAST). The MHD is a measure of how far two subsets are from each other. The smaller the value of MHD, the more similar the two point sets are. This analysis showed that the intracluster light distribution seen in the Hubble Frontier Fields images matched the mass distribution of the six galaxy clusters better than did X-ray emission, as derived from archived observations from Chandra X-ray Observatory’s Advanced CCD Imaging Spectrometer (ACIS).


Beyond this initial study, Montes and Trujillo see multiple opportunities to expand their research. To start, they would like to increase the radius of observation in the original six clusters, to see if the degree of tracing accuracy holds up. Another important test of their method will be observation and analysis of additional galaxy clusters by more research teams, to add to the data set and confirm their findings.


The astronomers also look forward to the application of the same techniques with future powerful space-based telescopes like the James Webb Space Telescope and WFIRST, which will have even more sensitive instruments for resolving faint intracluster light in the distant universe.


Trujillo would like to test scaling down the method from massive galaxy clusters to single galaxies. “It would be fantastic to do this at galactic scales, for example exploring the stellar halos. In principal the same idea should work; the stars that surround the galaxy as a result of the merging activity should also be following the gravitational potential of the galaxy, illuminating the location and distribution of dark matter.”



Hubble Space Telescope (HST). Animation Credits: NASA/ESA

The Hubble Frontier Fields program was a deep imaging initiative designed to utilize the natural magnifying glass of galaxy clusters’ gravity to see the extremely distant galaxies beyond them, and thereby gain insight into the early (distant) universe and the evolution of galaxies since that time. In that study the diffuse intracluster light was an annoyance, partially obscuring the distant galaxies beyond. However, that faint glow could end up shedding significant light on one of astronomy’s great mysteries: the nature of dark matter.


The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.


Related links:


Dark Energy and Dark Matter: http://www.nasa.gov/subject/6891/dark-energy-and-dark-matter/


Hubble Space Telescope (HST): https://www.nasa.gov/mission_pages/hubble/main/index.html


Images (mentioned), Animation (mentioned), Text, Credits: NASA/Karl Hille/Space Telescope Science Institute/Leah Ramsay/Ray Villard/University of New South Wales, Sydney, Australia/Mireia Montes.


Greetings, Orbiter.chArchive link


10 Ground-breaking Earth Satellite Images from 2018

In 2018, our satellites captured beautiful imagery from throughout the solar system and beyond. However, some of our favorite visualizations are of this very planet. While this list is by no means exhaustive, it does capture some Earth satellite images from this year that are both visually striking as well as scientifically informative. This list also represents a broad variety of Earth’s features, as well as satellite instrumentation. Take a journey with our eyes in the sky!


10. Hurricane Florence


image

Before making landfall, Hurricane Florence churned in the Atlantic for a full two weeks — making it among the longest-lived cyclones of the 2018 season. When it finally did hit land on Sep. 14, the storm devastated the southeastern U.S. coast with intense winds, torrential rains and severe flooding.


This natural-color image was acquired by MODIS on the Terra Satellite on Sep. 12, 2018. 


Images like this, as well as other satellite information, were used to anticipate the impact of the storm. Our Disasters Program created flood proxy maps that were shared with the Federal Emergency Management Agency (FEMA) and the National Guard to estimate how many and which communities would be most affected by the storm, in order to help prepare recovery efforts ahead of time.


9. Australia’s Lake Eyre Basin


image

The Lake Eyre Basin covers one-sixth of Australia and is one of the world’s largest internally draining river systems. However, the rivers supported by this system are ephemeral, meaning that they only run for short periods of time following unpredictable rain — the rest of the time, the Basin is a dry, arid desert.


However, when the heavy rain comes, the basin erupts in an explosion of green. In this false-color image captured by the Operational Land Imager (OLI) on Landsat 8 on Apr. 25, 2018, you can see how the vegetation completely envelops the spaces where the water has receded. (Flood water is indicated by light blue, and vegetation is indicated by light green.)


Satellites are an excellent tool for tracking greening events that are followed by flooding. These events offer opportunities for predictive tools as well as recreation.


8. Alaska’s Chukchi Sea 


image

A Monet painting comes to life as the Chukchi Sea swirls with microscopic marine algae.


This image was captured off the Alaskan coast by OLI on Landsat 8 on Jun. 18, 2018. After the Arctic sea ice breaks up each spring, the nutrient-rich Bering Sea water mixes with the nutrient-poor Alaskan coastal water. Each type of water brings with it a different type of phytoplankton and the surface waters have just enough light for the algae to populate and flourish. The result is these mesmerizing patterns of turquoise and green.


This image represents one piece of much larger, incredibly complex ecosystem. While one would not normally associate the breaking up of sea ice with phytoplankton blooms, it is an intricate process of the phytoplankton life cycle. The size of the blooms have varied greatly from year to year, and experts are unsure why. Images like these can help scientists track the development of these blooms and link it to other environmental changes.


7. Hawaii’s Kilauea 


image

Sometimes fresh lava is best viewed in infrared.


This false-color image of Kilauea, captured by OLI on Landsat 8 on May 23, 2018, shows the infrared signal emitted by lava flowing toward the sea. The purple areas surrounding the glowing lava are clouds lit from below, indicating that this image was taken through a break in the clouds.


The Puʻu ʻŌʻō Kupaianaha eruption has been continuously spewing red-hot lava since 1983, making it the longest eruption at Kilauea in recorded history. However, new fissures opened up this year that forced many to evacuate the area. Hawaii’s largest lake evaporated in hours and hundreds of homes were destroyed in Vacationland and Kapoho


Imagery, seismometers and ground-based instruments were used to track the underground movement of magma. Infrared imagery can be incredibly helpful in disasters like this when you to view data that cannot be observed with the naked eye. 


6. California’s Woolsey Burn Scar


image

Nothing quite encapsulates the destruction of a wildfire like a photo from outer space.


This image of the Woolsey Fire aftermath in Southern California was captured on Nov. 18, 2018 by the Advanced Spaceborned Thermal Emission and Reflection Radiometer (ASTER) on the Terra satellite. This false-color infrared image has been enhanced to clearly show the burned vegetation (indicated by brown) and the vegetation that survived unscathed (indicated by green).


The Woolsey Fire clearly left its mark, with almost 152 square miles (394 square km) and 88% of the Santa Monica Mountains National Recreation Area badly burned. Images like this one can assist fire managers in the area plan for recovery


5. Bangladesh’s Padma River


image

As the years go by, the Padma River grows and shrinks, twists and turns. It never has a fixed shape, and as a result, thousands of people must regularly adapt to the constant changes in the river’s 75-mile (130-km) shoreline.


This image captured on Jan. 20, 2018 by OLI on Landsat 8 depicts one of the major rivers of Bangladesh. For thirty years, scientists have been tracking the erosion of the river with satellite imagery. Combinations of shortwave infrared, near infrared, and visible light are used to detect differences year-to-year in width, depth, and shape of the river. Sometimes the river splits off, but then rejoins again later. These patterns are created by the river carrying and depositing sediment, shaping the curves of the path of water.


Monitoring the Padma River is going to become especially important as a new bridge development project advances in the Char Janajat area. Although the bridge will most certainly help shorten travel times for citizens, nobody is quite sure how the river erosion might affect the construction and vice versa. 


4. Alaska’s Yakutat Glacier 


image

It’s hard to believe that Harlequin Lake was once all dry land — but it only started to form once Yakutat Glacier started melting. The lake appeared at the beginning of the twentieth century, and has been growing rapidly ever since.


In this hauntingly beautiful image, captured on Sep. 21 2018 by OLI on Landsat 8, the effect of climate change is apparent — especially when compared to earlier images of the region.


The sad reality is that this image may be one of the last of Yakutat Glacier. Unless the climate warming starts to reverse very soon — which scientists consider very unlikely — Yakutat could be gone as soon as 2070.


3. South Africa’s Theewaterskloof


image

Cape Town is a seaside city planted on the tip of South Africa. It’s a city known for its beaches and biodiversity — it also almost became known as the first major city to officially run out of water.


This image of Cape Town’s largest reservoir — Theewaterskloof — was acquired on Jul. 9th, 2018 by OLI on Landsat 8. By the time this photo was taken, the city’s main reservoirs stood at 55%. This was a huge increase from where it stood just six months earlier: just 13%.


The severe water shortage in the region started in 2015, only to become more threatening after three successive and unusually dry years. The entire city was preparing for Day Zero — the day the tap water would be shut off.  


Despite forecasts that Day Zero would arrive in April, a combination of heavier rains and local conservation efforts restored the majority of the reservoir. 


2. Aerosol Earth


image

Aerosols are all around us. From the smoke from a fire, to the dust in the wind to the salt in sea spray — these solid particles and liquid droplets are always swirling in our atmosphere, oftentimes unseen.


The Goddard Earth Observing System Forward Processing (GEOS FP) model uses mathematical equations to model what is happening in our atmosphere. The inputs for its equations — temperature, moisture, wind, etc. — come from our satellites and ground sensors.


This visualization was compiled on Aug. 24, 2018 — obviously a busy day for aerosols in our atmosphere. Swirls of sea salt (indicated by blue) reveal typhoons Soulik and Cimaron heading straight towards South Korea and Japan. A haze of black carbon (indicated by red) suffuse from agricultural burning in Africa and large wildfires in North America. And clouds of dust (indicated by purple) float off the Sahara desert.


1. Camp Fire


image

With nearly a hundred fatalities, hundreds of thousands of acres burned and billions of dollars of damage, the world watched in horror as Camp Fire grew to become the most destructive California wildfire.


This image was captured on Nov. 8, 2018 by OLI on Landsat 8 on the same day Camp Fire ignited. It consolidates both visible light and shortwave-infrared light in order to highlight the active fire. Strong winds and dry conditions literally fanned the flames and spread this wildfire like a rash. 


This image has not only become the iconic portrait for Camp Fire, it is also sobering representation of how quickly a fire can grow out of control in a short amount of time. Even from space, you can almost smell the massive plumes of smoke and feel the heat of the fires.




Whether you realize it or not, our Earth satellite missions are collecting data everyday in order to monitor environmental changes and prepare for natural disasters.  If your interest is piqued by this list, head over to the Earth Observatory. The Earth Observatory updates daily with fresh, new content — brought to you by none other than our eyes in the sky. 


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


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