Coronavirus: Drive through testing begins at Edinburgh hospital

The chief medical officer warns it is “just a matter of time” before someone tests positive.

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Why is there any matter in the universe at all? New study sheds light

Scientists at the University of Sussex have measured a property of the neutron — a fundamental particle in the universe — more precisely than ever before. Their research is part of an investigation into why there is matter left over in the universe, that is, why all the antimatter created in the Big Bang didn’t just cancel out the matter.

The team — which included the Science and Technology Facilities Council’s (STFC) Rutherford Appleton Laboratory in the UK, the Paul Scherrer Institute (PSI) in Switzerland, and a number of other institutions — was looking into whether or not the neutron acts like an “electric compass.” Neutrons are believed to be slightly asymmetrical in shape, being slightly positive at one end and slightly negative at the other — a bit like the electrical equivalent of a bar magnet. This is the so-called “electric dipole moment” (EDM), and is what the team was looking for.

This is an important piece of the puzzle in the mystery of why matter remains in the Universe, because scientific theories about why there is matter left over also predict that neutrons have the “electric compass” property, to a greater or lesser extent. Measuring it then it helps scientists to get closer to the truth about why matter remains.

The team of physicists found that the neutron has a significantly smaller EDM than predicted by various theories about why matter remains in the universe; this makes these theories less likely to be correct, so they have to be altered, or new theories found. In fact it’s been said in the literature that over the years, these EDM measurements, considered as a set, have probably disproved more theories than any other experiment in the history of physics. The results are reported today, Friday 28 February 2020, in the journal Physical Review Letters.

Professor Philip Harris, Head of the School of Mathematical and Physical Sciences and leader of the EDM group at the University of Sussex, said:

“After more than two decades of work by researchers at the University of Sussex and elsewhere, a final result has emerged from an experiment designed to address one of the most profound problems in cosmology for the last fifty years: namely, the question of why the Universe contains so much more matter than antimatter, and, indeed, why it now contains any matter at all. Why didn’t the antimatter cancel out all the matter? Why is there any matter left?

“The answer relates to a structural asymmetry that should appear in fundamental particles like neutrons. This is what we’ve been looking for. We’ve found that the “electric dipole moment” is smaller than previously believed. This helps us to rule out theories about why there is matter left over — because the theories governing the two things are linked.

“We have set a new international standard for the sensitivity of this experiment. What we’re searching for in the neutron — the asymmetry which shows that it is positive at one end and negative at the other — is incredibly tiny. Our experiment was able to measure this in such detail that if the asymmetry could be scaled up to the size of a football, then a football scaled up by the same amount would fill the visible Universe.”

The experiment is an upgraded version of apparatus originally designed by researchers at the University of Sussex and the Rutherford Appleton Laboratory (RAL), and which has held the world sensitivity record continuously from 1999 until now.

Dr Maurits van der Grinten, from the neutron EDM group at the Rutherford Appleton Laboratory (RAL), said:

“The experiment combines various state of the art technologies that all need to perform simultaneously. We’re pleased that the equipment, technology and expertise developed by scientists from RAL has contributed to the work to push the limit on this important parameter”

Dr Clark Griffith, Lecturer in Physics from the School of Mathematical and Physical Sciences at the University of Sussex, said:

“This experiment brings together techniques from atomic and low energy nuclear physics, including laser-based optical magnetometry and quantum-spin manipulation. By using these multi-disciplinary tools to measure the properties of the neutron extremely precisely, we are able to probe questions relevant to high-energy particle physics and the fundamental nature of the symmetries underlying the universe. “

50,000 measurements

Any electric dipole moment that a neutron may have is tiny, and so is extremely difficult to measure. Previous measurements by other researchers have borne this out. In particular, the team had to go to great lengths to keep the local magnetic field very constant during their latest measurement. For example, every truck that drove by on the road next to the institute disturbed the magnetic field on a scale that would have been significant for the experiment, so this effect had to be compensated for during the measurement.

Also, the number of neutrons observed needed to be large enough to provide a chance to measure the electric dipole moment. The measurements ran over a period of two years. So-called ultracold neutrons, that is, neutrons with a comparatively slow speed, were measured. Every 300 seconds, a bunch of more than 10,000 neutrons was directed to the experiment and examined in detail. The researchers measured a total of 50,000 such bunches.

A new international standard is set

The researchers’ latest results supported and enhanced those of their predecessors: a new international standard has been set. The size of the EDM is still too small to measure with the instruments that have been used up until now, so some theories that attempted to explain the excess of matter have become less likely. The mystery therefore remains, for the time being.

The next, more precise, measurement is already being constructed at PSI. The PSI collaboration expects to start their next series of measurements by 2021.

Search for “new physics”

The new result was determined by a group of researchers at 18 institutes and universities in Europe and the USA on the basis of data collected at PSI’s ultracold neutron source. The researchers collected measurement data there over a period of two years, evaluated it very carefully in two separate teams, and were then able to obtain a more accurate result than ever before.

The research project is part of the search for “new physics” that would go beyond the so-called Standard Model of Physics, which sets out the properties of all known particles. This is also a major goal of experiments at larger facilities such as the Large Hadron Collider (LHC) at CERN.

The techniques originally developed for the first EDM measurement in the 1950s led to world-changing developments such as atomic clocks and MRI scanners, and to this day it retains its huge and ongoing impact in the field of particle physics.

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Ultrafast probing reveals intricate dynamics of quantum coherence

Ultrafast, multidimensional spectroscopy unlocks macroscopic-scale effects of quantum electronic correlations.

Researchers found that low-energy and high energy states are correlated in a layered, superconducting material LSCO (lanthanum, strontium, copper, oxygen).

Exciting the material with an ultrafast (<100fs), beam of near-infrared light produces coherent excitations lasting a surprisingly ‘long’ time of around 500 femtoseconds, originating from a quantum superposition of excited states within the crystal.

The strong correlation between the energy of this coherence and the optical energy of the emitted signal indicates a coherent interaction between the states at low and high energy.

This kind of coherent interaction, reported here for the first time, is the root of many intriguing and poorly-understood phenomena displayed by quantum materials.

It is one of the first applications of multidimensional spectroscopy to study of correlated electron systems such as high-temperature superconductors.

PROBING QUANTUM MATERIALS

The intriguing magnetic and electronic properties of quantum materials hold significant promise for future technologies.

However, controlling these properties requires an improved understanding of the ways in which macroscopic behaviour emerges in complex materials with strong electronic correlations.

Potentially useful electric and magnetic properties of quantum materials with strong electronic correlations include: Mott transition, colossal magnetoresistance, topological insulators, and high-temperature superconductivity.

Such macroscopic properties emerge out of microscopic complexity, rooted in the competing interactions between the degrees of freedom (charge, lattice, spin, orbital, and topology) of electronic states.

While measurements of the dynamics of excited electronic populations have been able to give some insight, they have largely neglected the intricate dynamics of quantum coherence.

In this new study, researchers applied multidimensional coherent spectroscopy to the challenge for the first time, utilising the technique’s unique capability to differentiate between competing signal pathways, selectively exciting and probing low-energy excitations.

Researchers analysed the quantum coherence of excitations produced by hitting LSCO (lanthanum, strontium, copper and oxygen) crystals with a sequence of tailored, ultrafast beams of near-infrared light lasting less than 100 femtoseconds

This coherence has unusual properties, lasts a surprisingly ‘long’ time of around 500 femtoseconds, and originates from a quantum superposition of excited states within the crystal.

2D spectrum showing energy difference between the states in the quantum superposition, shown before, during and after pulse overlap

“We found a strong correlation between the energy of this coherence and the optical energy of the emitted signal, which indicates a special coherent interaction between the states at low and high energy in these complex systems,” says study author Jeff Davis (Swinburne University of Technology).

Because the number of available excitations affects the band structure of a crystal, the effective energy structure changes transiently during measurement, which links low-energy excitations and optically excited electronic states.

The study demonstrates that multidimensional coherent spectroscopy can interrogate complex quantum materials in unprecedented ways.

As well as representing a major advancement in ultrafast spectroscopy of correlated materials, the work has wider significance in optics/photonics, chemistry, nanoscience, and condensed-matter science.

THE STUDY

Persistent coherence of quantum superpositions in an optimally doped cuprate revealed by 2D spectroscopy was published in Science Advances in February 2020.

The authors acknowledge funding by the Australian Research Council (Future Fellowship and Centres of Excellence programs). Work was conducted at the Centre for Quantum and Optical Science (Swinburne University of Technology), Ruhr University (Germany) and University of Oxford (UK).

ULTRAFAST SPECTROSCOPY AT FLEET

Within FLEET, Jeff Davis uses ultrafast spectroscopy to study and control the microscopic interactions in 2D materials and how they lead to macroscopic behaviour.

In FLEET’s third research theme, light-transformed materials, systems are temporarily driven out of thermal equilibrium to investigate the qualitatively different physics displayed and new capabilities for dynamically controlling their behaviour.

FLEET is an Australian Research Council-funded research centre bringing together over a hundred Australian and international experts to develop a new generation of ultra-low energy electronics.

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Novel coronavirus (COVID-19) imaging features overlap with SARS and MERS

Although the imaging features of novel coronavirus disease 2019 (COVID-19) are variable and nonspecific, the findings reported thus far do show “significant overlap” with those of severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), according to an ahead-of-print article in the American Journal of Roentgenology (AJR).

COVID-19 is diagnosed on the presence of pneumonia symptoms (e.g., dry cough, fatigue, myalgia, fever, dyspnea), as well as recent travel to China or known exposure, and chest imaging plays a vital role in both assessment of disease extent and follow-up.

As per her review of the present clinical literature concerning COVID-19, Melina Hosseiny of the University of California at Los Angeles concluded: “Early evidence suggests that initial chest imaging will show abnormality in at least 85% of patients, with 75% of patients having bilateral lung involvement initially that most often manifests as subpleural and peripheral areas of ground-glass opacity and consolidation.”

Furthermore, “older age and progressive consolidation” may imply an overall poorer prognosis.

Unlike SARS and MERS — where initial chest imaging abnormalities are more frequently unilateral — COVID-19 is more likely to involve both lungs on initial imaging.

“To our knowledge,” Hosseiny et al. continued, “pleural effusion, cavitation, pulmonary nodules, and lymphadenopathy have not been reported in patients with COVID-19.”

Ultimately, the authors of this AJR article recommended CT for follow-up in patients recovering from COVID-19 to evaluate long-term or even permanent pulmonary damage, including fibrosis — as seen in SARS and MERS infections.

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Materials provided by American Roentgen Ray Society. Note: Content may be edited for style and length.

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COVID-19 a reminder of the challenge of emerging infectious diseases

The emergence and rapid increase in cases of coronavirus disease 2019 (COVID-19), a respiratory illness caused by a novel coronavirus, pose complex challenges to the global public health, research and medical communities, write federal scientists from NIH’s National Institute of Allergy and Infectious Diseases (NIAID) and from the Centers for Disease Control and Prevention (CDC). Their commentary appears in The New England Journal of Medicine.

NIAID Director Anthony S. Fauci, M.D., NIAID Deputy Director for Clinical Research and Special Projects H. Clifford Lane, M.D., and CDC Director Robert R. Redfield, M.D., shared their observations in the context of a recently published report on the early transmission dynamics of COVID-19. The report provided detailed clinical and epidemiological information about the first 425 cases to arise in Wuhan, Hubei Province, China.

In response to the outbreak, the United States and other countries instituted temporary travel restrictions, which may have slowed the spread of COVID-19 somewhat, the authors note. However, given the apparent efficiency of virus transmission, everyone should be prepared for COVID-19 to gain a foothold throughout the world, including in the United States, they add. If the disease begins to spread in U.S. communities, containment may no longer be a realistic goal and response efforts likely will need to transition to various mitigation strategies, which could include isolating ill people at home, closing schools and encouraging telework, the officials write.

Drs. Fauci, Lane and Redfield point to the many research efforts now underway to address COVID-19. These include numerous vaccine candidates proceeding toward early-stage clinical trials as well as clinical trials already underway to test candidate therapeutics, including an NIAID-sponsored trial of the experimental antiviral drug remdesivir that began enrolling participants on February 21, 2020.

“The COVID-19 outbreak is a stark reminder of the ongoing challenge of emerging and re-emerging infectious pathogens and the need for constant surveillance, prompt diagnosis and robust research to understand the basic biology of new organisms and our susceptibilities to them, as well as to develop effective countermeasures,” the authors conclude.

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Materials provided by NIH/National Institute of Allergy and Infectious Diseases. Note: Content may be edited for style and length.

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Physiotherapy could be done at home using virtual reality

Virtual reality could help physiotherapy patients complete their exercises at home successfully thanks to researchers at WMG, University of Warwick, who managed to combine VR technology with 3D motion capture.

Currently prescribed physiotherapy often requires patients to complete regular exercises at home. Outside of the clinic, patients rarely receive any guidance other than a leaflet of sketches or static photographs to instruct them how to complete their exercises. This leads to poor adherence, with patients becoming anxious about not getting the exercise right, or simply getting bored by the repetitiveness of the movements.

The advent of consumer virtual reality technology combined with 3D motion capture allows real movements to be accurately translated onto an avatar that can be viewed in a virtual environment. Researchers at the Institute of Digital Healthcare, WMG, University of Warwick are investigating whether this technology can be used to provide guidance to physiotherapy patients, by providing a virtual physiotherapist in the home to demonstrate the prescribed exercises.

Their paper, ‘Timing and correction of stepping movements with a virtual reality avatar’ published today the 28th of February, in the Journal PLOS ONE, has focused on whether people are able to accurately follow the movements of a virtual avatar.

Researchers had to investigate whether people were able to accurately coordinate and follow the movements of an avatar in a virtual environment. They asked participants to step in time with an avatar viewed through a VR headset.

Unknown to the participants, the researchers subtly slowed down or speeded up one of the avatar’s steps, such that the participants would have to correct their own stepping movement to stay in time. The effect this correction had on their step timing and synchronisation with the avatar was measured.

Lead author, Omar Khan from WMG, University of Warwick commented:

“If participants were observed to correct their own stepping to stay in time with the avatar, we knew they were able to accurately follow the movements they were observing.

“We found that participants struggled to keep in time if only visual information was present. However, when we added realistic footstep sounds in addition to the visual information, the more realistic multisensory information allowed participants to accurately follow the avatar.”

Dr Mark Elliott, Principal investigator on the project at WMG, University of Warwick added:

“There is huge potential for consumer VR technologies to be used for both providing guidance to physiotherapy exercises, but also to make the exercises more interesting. This study has focused on the crucial question of how well people can follow a virtual guide.”

Prof. Theo Arvanitis, co-author and Director of the Institute of Digital Healthcare, said:

“Our work and digitally-enabled technological solution can underpin transformative health innovations to impact the field of physiotherapy, and have a direct benefit to patients’ rehabilitation. “We now plan to investigate other types of movements working closely in partnership with physiotherapists, to establish the areas of physiotherapy that will benefit most from this technology.”

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Materials provided by University of Warwick. Note: Content may be edited for style and length.

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Hunter-gatherer networks accelerated human evolution

Humans began developing a complex culture as early as the Stone Age. This development was brought about by social interactions between various groups of hunters and gatherers, a UZH study has now confirmed. The researchers mapped the social networks of present-day hunter-gatherers in the Philippines and simulated the discovery of a medicinal plant product.

Around 300,000 years ago, our ancestors lived in small communities as hunters and gatherers. This lifestyle likely played a central role in humanity’s success, as it enabled humans to start sharing and combining their individual knowledge with others and in this way come up with innovative solutions. This unique capacity is what distinguishes us from our closest relatives, the chimpanzees.

Insights into this process can be gained by studying the few remaining hunter-gatherer societies, such as the Agta people, who live in the Philippines. An international research team has now investigated the social network of Agta hunter-gatherers to shed light on the evolution of culture. The study was led by Andrea Migliano and Lucio Vinicius from the Department of Anthropology of the University of Zurich as well as Federico Battiston from the Central European University in Budapest.

Inter-camp visits as social media

The researchers equipped 53 adult Agta living in woodland in seven interconnected residential camps with tracking devices and recorded every social interaction between members of the different camps over a period of one month. The researchers also did the same for a different group, who lived on the coast.

During this time, the tracking devices documented thousands of interactions and provided a comprehensive picture of the Agta’s social structure. As expected, people most frequently interacted with members of their own camp, but the study also revealed inter-camp visits almost on a daily basis. “It is fair to say that ‘visits between camps’ is the social media of current hunter-gatherers,” says first author Andrea Migliano, professor of anthropology at UZH. When we need a new solution for a problem, we go online and use multiple sources to obtain information from a variety of people. Hunter-gatherers use their social network in exactly the same way.”

Simulated creation of medicine

The team of researchers then developed a computer model of this social structure and simulated the complex cultural creation of a plant-based medicinal product. In this fictitious scenario, the people shared their knowledge of medicinal plants with every encounter and combined this knowledge to develop better remedies. This process gradually leads to the development of a highly effective new medicinal product. According to the researchers’ simulation, an average of 250 (woodland camps) to 500 (coastal camps) rounds of social interactions were required for the medicinal product to emerge.

Human interaction accelerates innovation

Next, the researchers simulated the same scenario using an artificial and fully connected network, where all individuals were connected to each other and immediately transmitted any new information to all members of the network. Surprisingly, in this scenario it took longer for the new medicine to develop — necessitating about 500 to 700 rounds. The reason is that the artificial network spread innovations one step at a time, whereas in the real hunter-gatherer networks new discoveries can also develop in parallel in small clusters, which ultimately results in quicker progress being made.

“Our findings indicate that this social structure of small and interconnected bands may have facilitated the sequence of cultural and technological revolutions that characterizes our species as we expanded within and then out of Africa,” concludes last author Lucio Vinicius, from UZH’s Department of Anthropology.

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Materials provided by University of Zurich. Note: Content may be edited for style and length.

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Betelgeuse: A massive star’s dying breaths

Betelgeuse has been the center of significant media attention lately. The red supergiant is nearing the end of its life, and when a star over 10 times the mass of the Sun dies, it goes out in spectacular fashion. With its brightness recently dipping to the lowest point in the last hundred years, many space enthusiasts are excited that Betelgeuse may soon go supernova, exploding in a dazzling display that could be visible even in daylight.

While the famous star in Orion’s shoulder will likely meet its demise within the next million years — practically couple days in cosmic time — scientists maintain that its dimming is due to the star pulsating. The phenomenon is relatively common among red supergiants, and Betelgeuse has been known for decades to be in this group.

Coincidentally, researchers at UC Santa Barbara have already made predictions about the brightness of the supernova that would result when a pulsating star like Betelgeuse explodes.

Physics graduate student Jared Goldberg has published a study with Lars Bildsten, director of the campus’s Kavli Institute for Theoretical Physics (KITP) and Gluck Professor of Physics, and KITP Senior Fellow Bill Paxton detailing how a star’s pulsation will affect the ensuing explosion when it does reach the end. The paper appears in the Astrophysical Journal.

“We wanted to know what it looks like if a pulsating star explodes at different phases of pulsation,” said Goldberg, a National Science Foundation graduate research fellow. “Earlier models are simpler because they don’t include the time-dependent effects of pulsations.”

When a star the size of Betelgeuse finally runs out of material to fuse in its center, it loses the outward pressure that kept it from collapsing under its own immense weight. The resultant core collapse happens in half a second, far faster than it takes the star’s surface and puffy outer layers to notice.

As the iron core collapses the atoms disassociate into electrons and protons. These combine to form neutrons, and in the process release high-energy particles called neutrinos. Normally, neutrinos barely interact with other matter — 100 trillion of them pass through your body every second without a single collision. That said, supernovae are among the most powerful phenomena in the universe. The numbers and energies of the neutrinos produced in the core collapse are so immense that even though only a tiny fraction collides with the stellar material, it’s generally more than enough to launch a shockwave capable of exploding the star.

That resulting explosion smacks into the star’s outer layers with stupefying energy, creating a burst that can briefly outshine an entire galaxy. The explosion remains bright for around 100 days, since the radiation can escape only once ionized hydrogen recombines with lost electrons to become neutral again. This proceeds from the outside in, meaning that astronomers see deeper into the supernova as time goes on until finally the light from the center can escape. At that point, all that’s left is the dim glow of radioactive fallout, which can continue to shine for years.

A supernova’s characteristics vary with the star’s mass, total explosion energy and, importantly, its radius. This means Betelgeuse’s pulsation makes predicting how it will explode rather more complicated.

The researchers found that if the entire star is pulsating in unison — breathing in and out, if you will — the supernova will behave as though Betelgeuse was a static star with a given radius. However, different layers of the star can oscillate opposite each other: the outer layers expand while the middle layers contract, and vice versa.

For the simple pulsation case, the team’s model yielded similar results to the models that didn’t account for pulsation. “It just looks like a supernova from a bigger star or a smaller star at different points in the pulsation,” Goldberg explained. “It’s when you start considering pulsations that are more complicated, where there’s stuff moving in at the same time as stuff moving out — then our model actually does produce noticeable differences,” he said.

In these cases, the researchers discovered that as light leaks out from progressively deeper layers of the explosion, the emissions would appear as though they were the result of supernovae from different sized stars.

“Light from the part of the star that is compressed is fainter,” Goldberg explained, “just as we would expect from a more compact, non-pulsating star.” Meanwhile, light from parts of the star that were expanding at the time would appear brighter, as though it came from a larger, non-pulsating star.

Goldberg plans to submit a report to Research Notes of the American Astronomical Society with Andy Howell, a professor of physics, and KITP postdoctoral researcher Evan Bauer summarizing the results of simulations they ran specifically on Betelgeuse. Goldberg is also working with KITP postdoc Benny Tsang to compare different radiative transfer techniques for supernovae, and with physics graduate student Daichi Hiramatsu on comparing theoretical explosion models to supernova observations.

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Examining ice giants of our solar system

Far-flung Uranus and Neptune — the ice giants of our solar system — are as mysterious as they are distant. Soon after its launch in 2021, NASA’s James Webb Space Telescope will change that by unlocking secrets of the atmospheres of both planets.

The cold and remote giant planets Uranus and Neptune are nicknamed the “ice giants” because their interiors are compositionally different from Jupiter and Saturn, which are richer in hydrogen and helium, and are known as the “gas giants.” The ice giants are also much smaller than their gaseous cousins, being intermediate in size between terrestrial planets and the gas giants. They represent the least-explored category of planet in our solar system. Scientists using Webb plan to study the circulation patterns, chemistry and weather of Uranus and Neptune in a way only Webb can.

“The key thing that Webb can do that is very, very difficult to accomplish from any other facility is map their atmospheric temperature and chemical structure,” explained the studies’ leader, Leigh Fletcher, an associate professor of planetary science at the University of Leicester in the United Kingdom. “We think that the weather and climate of the ice giants are going to have a fundamentally different character compared to the gas giants. That’s partly because they’re so far away from the Sun, they’re smaller in size and rotate slower on their axes, but also because the blend of gases and the amount of atmospheric mixing is very different compared with Jupiter and Saturn.”

All the gases in the upper atmospheres of Uranus and Neptune have unique chemical fingerprints that Webb can detect. Crucially, Webb can distinguish one chemical from another. If these chemicals are being produced by sunlight interacting with the atmosphere, or if they’re being redistributed from place to place by large-scale circulation patterns, Webb will be able to see that.

These studies will be conducted through a Guaranteed Time Observations (GTO) program of the solar system led by Heidi Hammel, a planetary scientist and Webb Interdisciplinary Scientist. She is also Vice President for Science at the Association of Universities for Research in Astronomy (AURA) in Washington, D.C. Hammel’s program will demonstrate the capabilities of Webb for observing solar system objects and exercise some of Webb’s specific techniques for objects that are bright and/or are moving in the sky.

Uranus: The Tilted Planet

Unlike the other planets in our solar system, Uranus — along with its rings and moons — is tipped on its side, rotating at roughly a 90-degree angle from the plane of its orbit. This makes the planet appear to roll like a ball around the Sun. That weird orientation — which may be the result of a gargantuan collision with another massive protoplanet early in the formation of the solar system — gives rise to extreme seasons on Uranus.

When NASA’s Voyager 2 spacecraft flew by Uranus in 1986, one pole was pointing directly at the Sun. “No matter how much Uranus would spin,” Hammel explained, “one half was in complete sunlight all the time, and the other half was in total darkness. It’s the craziest thing you can imagine.”

Disappointingly, Voyager 2 saw only a billiard-ball smooth planet covered in haze, with only a scant handful of clouds. But when Hubble viewed Uranus in the early 2000s, the planet had traveled a quarter of the way around in its orbit. Now the equator was pointed at the Sun, and the entire planet was illuminated over the course of a Uranian day.

“Theory told us nothing would change,” said Hammel, “But the reality was that Uranus started sprouting up all kinds of bright clouds, and a dark spot was discovered by Hubble. The clouds seemed to be changing dramatically in response to the immediate change in sunlight as the planet traveled around the Sun.”

As the planet continues its slow orbital trek, it will point its other pole at the Sun in 2028.

Webb will give insight into the powerful seasonal forces driving the formation of its clouds and weather, and how this is changing with time. It will help determine how energy flows and is transported through the Uranian atmosphere. Scientists want to watch Uranus throughout Webb’s life, to build up a timeline of how the atmosphere responds to the extreme seasons. That will help them understand why this planet’s atmosphere seems to go through periods of intense activity punctuated by moments of calm.

Neptune: A World of Supersonic Winds

Neptune is a dark, cold world, yet it is whipped by supersonic winds that can reach up 1,500 miles per hour. More than 30 times as far from the Sun as Earth, Neptune is the only planet in our solar system not visible to the naked eye. Its existence was predicted by mathematics before its discovery in 1846. In 2011, Neptune completed its first 165-year orbit since its discovery.

Like Uranus, this ice giant’s very deep atmosphere is made of a thick soup of water, ammonia, hydrogen sulfide and methane over an unknown and inaccessible interior. The accessible upper layers of the atmosphere are made of hydrogen, helium and methane. As with Uranus, the methane gives Neptune its blue color, but some still-mysterious atmospheric chemistry makes Neptune’s blue a bit more striking than that of Uranus.

“It’s the same question here: How does energy flow and how is it transported through a planetary atmosphere?” explained Fletcher. “But in this case, unlike Uranus, the planet has a strong internal heat source. That heat source generates some of the most powerful winds and the most short-lived atmospheric vortices and cloud features of anywhere in the solar system. If we look at Neptune from night to night, its face is always shifting and changing as these clouds are stretched and pulled and manipulated by the underlying wind field.”

Following the 1989 Voyager 2 flyby of Neptune, scientists discovered a bright, hot vortex — a storm — at the planet’s south pole. Because the temperature there is higher than everywhere else in the atmosphere, this region is likely associated with some unique chemistry. Webb’s sensitivity will allow scientists to understand the unusual chemical environment within that polar vortex.

Just the Beginning

Fletcher advises to be prepared for seeing phenomena on Uranus and Neptune that are totally unlike what we’ve witnessed in the past. “Webb really has the capability to see the ice giants in a whole new light. But to understand the continual atmospheric processes that are shaping these giant planets, you really need more than just a couple of samples,” he said. “So we compare Jupiter to Saturn to Uranus to Neptune, and by that, we build up a wider picture of how atmospheres work in general. This is the beginning of understanding how these worlds are changing with time.”

Hammel added, “We now know of hundreds of exoplanets — planets around other stars — of the size of our local ice giants. Uranus and Neptune provide us ground truth for studies of these newly discovered worlds.”

The James Webb Space Telescope will be the world’s premier space science observatory when it launches in 2021. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

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Huntington’s disease: Woman with gene fails in bid to sue NHS

A woman claimed the NHS had a duty of care to tell her about her father’s fatal, inherited brain condition.

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