“What really surprised me about the results is that we may realistically find signs of life on other planets in the next 5 to 10 years,” said Caprice Phillips, a graduate student at The Ohio State University, who will share preliminary findings at a press conference during the 2021 APS April Meeting.

Gas dwarf planets have the potential to foster life. But because none of these super-Earths or mini-Neptunes exist within our solar system, scientists struggle to determine whether their atmospheres contain ammonia and other potential signs of living things.

Phillips calculated that when the James Webb Space Telescope launches this October, it could feasibly detect ammonia around six gas dwarf planets after just a few orbits.

She and her team modeled how JWST instruments would respond to varying clouds and atmospheric conditions, then produced a ranked list of where the telescope should search for life.

“Humankind has contemplated the questions, ‘Are we alone? What is life? Is life elsewhere similar to us?'” said Phillips. “My research suggests that for the first time, we have the scientific knowledge and technological capabilities to realistically begin to find the answers to these questions.”

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“Our Earth is 45 million centuries old. But this century is the first when one species — ours — can determine the biosphere’s fate,” said Martin Rees, the United Kingdom’s Astronomer Royal and a founder of the Centre for the Study of Existential Risks at Cambridge University.*

“Our globally-linked society is vulnerable to the unintended consequences of powerful new technologies — not only nuclear, but (even more) biotech, cyber, advanced AI, space technology,” he added.

Royal astronomer predicts the world in 2050 and beyond

Rees thinks biohackers pose a particularly underappreciated threat to humanity. In the near future, simple equipment will enable people to reengineer the human genome irrevocably or build a superspreading influenza. Like drug laws, regulations could never prevent all such actions — and in a world more interconnected than ever before, the consequences would spread globally.

He will discuss other dangers: population rise leading to plummeting biodiversity, disastrous climate change, uncontrollable cybercriminals, plans for artificial intelligence that erodes privacy, security, and freedom.

But Rees is an optimist. He will offer a path toward avoiding these risks and achieving a sustainable future better than the world we live in today.

“If all of us passengers on ‘spaceship Earth’ want to ensure that we leave it in better shape for future generations we need to promote wise deployment of new technologies, while minimizing the risk of pandemics, cyberthreats, and other global catastrophes,” he said.

Scaling back missile defense could prevent a nuclear attack

A single nuclear weapon could kill millions and destroy a city instantaneously. Hundreds of weapons could wipe out functioning society in a large nation. Even a limited nuclear war could cause a climate catastrophe, leading to the starvation of hundreds of millions of people.

Recently, Russia, China, and North Korea have deployed new types of nearly unstoppable missiles.

“Missile defense is an idea that can sound appealing at first — doesn’t defense sound like the right thing to do?” said Frederick Lamb, astrophysicist at the University of Illinois at Urbana-Champaign, cochair of the 2003 APS Study of Boost-Phase Missile Defense, and chair of the current APS Panel on Public Affairs Study of Missile Defense and National Security.

“But when the technical challenges and arms race implications are considered, one can see that deploying a system that is intended to defend against intercontinental ballistic missiles is unlikely to improve the security of the United States,” he said.

Lamb points to the United Kingdom’s decision to increase its nuclear arsenal by 44%, possibly motivated by Russia’s new missile defense system around Moscow. He sees the move as yet another sign that existing limits on nuclear weapons are unraveling. Even missile defenses that would never work in practice can catalyze the development of new nuclear weapons and increase global risk.

Lamb will share what may happen if the United States ramps up new missile defense systems.

“What is done about nuclear weapons and missile defenses by the United States and other countries affects the safety and survival of every person on the planet,” he said.

*Scientists will forecast the fate of the planet at a press conference during the 2021 APS April Meeting.

A joint research team led by Professor Junsuk Rho of departments of mechanical and chemical engineering and Dr. Inki Kim of Department of Mechanical Engineering with Professor Young-Ki Kim and Ph.D. candidate Won-Sik Kim of Department of Chemical Engineering at POSTECH has integrated metasurface with gas-reactive liquid crystal optical modulator to develop a sensor that provides an immediate visual holographic alarm when harmful gases are detected. The findings from this study were published in Science Advances on April 7, 2021.

For those working in hazardous environments such as petrochemical plants, gas sensors are life. However, conventional gas sensing devices are not widely used due to their high cost of being made with complex machines and electronic devices. In addition, commercial gas sensors have limitations in that they are difficult to use, and have poor portability and reaction speed.

To solve these issues, the research team utilized the metasurface, well known as a future optical device known to have the invisible cloak effect through making visible objects disappear by controlling the refractive index of light. Metasurface is especially used to transmit two-way holograms or 3D video images by freely controlling light.

Using the metasurface, the research team developed a gas sensor that can float a holographic image alarm in space in just a few seconds by using the polarization control of transmitted light that transforms due to the change in orientation of liquid crystal molecules in the liquid crystal layer inside the sensor device when exposed to gas. Moreover, this gas sensor developed by the research team requires no support from external mechanical or electronic devices, unlike other conventional commercial gas sensors. The researchers used isopropyl alcohol as the target hazardous gas, known as a toxic substance that can cause stomach pain, headache, dizziness, and even leukemia.

The newly developed sensor was confirmed to detect even the minute amount of gas of about 200ppm. In an actual experiment using a board marker, a volatile gas source in our daily life, a visual holographic alarm popped up instantaneously the moment the marker was brought to the sensor.

Moreover, the research team developed a one-step nanocomposite printing method to produce this flexible and wearable gas sensor. The metasurface structure, which was previously processed on a hard substrate, was designed to enable rapid production with a single-step nanocasting process on a curved or flexible substrate.

When the flexible sensor fabricated using this method attaches like a sticker on safety glasses, it can detect gas and display a hologram alarm. It is anticipated to be integrable with glass-type AR display systems under development at Apple, Samsung, Google, and Facebook.

Going a step further, the research team is developing a high-performance environmental sensor that can display the type and concentration level of gases or biochemicals in the surroundings with a holographic alarm, and is studying optical design techniques that can encode various holographic images. If these studies are successful, they can be used to reduce accidents caused by biochemical or gas leaks.

“This newly developed ultra-compact wearable gas sensor provides a more intuitive holographic visual alarm than the conventional auditory or simple light alarms,” remarked Prof. Junsuk Rho. “It is anticipated to be especially effective in more extreme work environments where acoustic and visual noise are intense.”

“All the stars aligned,” said Elke-Caroline Aschenauer, Brookhaven National Laboratory Staff Scientist and a leader in developing the EIC plans. “We have the technology to build this unique particle accelerator and detector to do the measurements that, together with the underlying theory, can for the first time provide answers to longstanding fundamental questions in nuclear physics.”

The EIC isn’t the only Brookhaven project poised to reshape nuclear and particle physics. Forthcoming data from the Relativistic Heavy Ion Collider could finally detect the elusive chiral magnetic effect. Meanwhile, planned accelerators could run on sustainable energy, a drastic departure from today’s machines.

At a press conference during the 2021 APS April Meeting, researchers will discuss how cutting-edge accelerators could collide with both energy consumption and our assumptions about the nature of matter.

A powerful new facility for nuclear physics

“The scientific advances of the EIC will help us all to understand where we come from and how the visible matter around us is composed from its elementary building blocks,” said Aschenauer.

The accelerator and detector will serve as a kind of camera, taking 3D images and movies of electrons colliding with polarized protons and ions. Like a CT scanner for atoms, the EIC will let scientists see how force-carrying gluon particles hold together quarks, the internal components of protons and neutrons. It will also offer insights into the spin of fundamental particles.

Aschenauer will give status updates from the first year of the EIC project — a collaboration between BNL and Thomas Jefferson National Accelerator Facility — and an overview of its experimental equipment.

Hunting for the chiral magnetic effect

The EIC will build on the Relativistic Heavy Ion Collider, which will soon produce major results of its own.

In summer 2021, data analysis will likely conclude on an experiment searching for decisive proof of the chiral magnetic effect. This proposed effect helps explain many fundamental features of the Standard Model and could unlock why our universe contains overwhelmingly more matter than antimatter, crucial to human existence.

Jinfeng Liao, a theoretical nuclear physicist at Indiana University Bloomington, will share key predictions about what the experiment might uncover.

“The signatures, as predicted by our theoretical study, show clear promise of unambiguously establishing the existence of chiral magnetic effect in the isobar collision experiment,” said Liao.

Liao and colleagues created a custom fluid-dynamics-based computational tool to simulate experimental collisions and any changes the chiral magnetic effect would cause.

They show that the new experiment has a better chance of detecting the effect than previous attempts, long plagued by weak signals and strong background contamination. The predictions were published in Physical Review Letters.

Probing profound subatomic questions requires a lot of power.

“Large particle accelerators use a shockingly large amount of energy,” said Georg Hoffstaetter, a professor at Cornell University.

He will share results from the Cornell-BNL Test Accelerator, or CBETA, the world’s first to accelerate a beam multiple times while powering itself by reusing beam energy. It further reduces electricity demands with superconducting and magnetic equipment.

The Energy Recovery Linacs technology that enables the test accelerator could lead to smaller particle accelerators with higher beam currents and reduced energy consumption.

“People may benefit from the industrial applications of Energy Recovery Linacs by using better computer chips, by being cured in radiation therapy centers that guide beams with permanent magnets, or by inhaling accelerator-produced medical isotopes,” said Hoffstaetter.

Building on the success of the test accelerator, its principal investigator and Brookhaven Senior Physicist Dejan Trbojevic will present designs for a new green energy collider. Particles speed along racetrack beam lines, formed from high-quality permanent magnets which require no use of electrical power.

“The ‘green accelerator’ shows a completely new way of accelerating particles with very tight control of their motion and with an extremely high energy range. It has never been done before,” said Trbojevic.

He will demonstrate how the EIC, as well as a similar accelerator under consideration at the Large Hadron Collider, could incorporate the energy-saving features.

An international team of researchers, including Carnegie Mellon University’s Saoirse Foley, set out on an ancestry.com-like investigation to find the answer to this question. They looked to the transcriptomes, the sum of all the transcripts from the mRNA, of many tarantulas and other spiders from different time periods. Their findings were published online by PeerJ on April 6.

They used the transcriptomes to build a genetic tree of spiders and then time-calibrated their tree with fossil data. Tarantula fossils are extremely rare, but the software used in the study managed to estimate the ages of older tarantulas relative to the ages of fossils from other spiders.

They found that tarantulas are ancient, first emerging in the piece of land now considered the Americas about 120 million years ago during the Cretaceous period. At that time South America would have been attached to Africa, India and Australia as part of the Gondwana supercontinent. The spiders ultimately reached their present destinations due to continental drift, with a few interesting departures.

For example, the nature of their entry into Asia suggests tarantulas may also be surprisingly proficient dispersers. The researchers were able to establish two separate lineages of tarantulas that diverged on the Indian subcontinent before it crashed into Asia, with one lineage being predominantly ground dwelling and the other predominantly arboreal. They found that these lineages colonized Asia about 20 million years apart. Surprisingly, the first group that reached Asia also managed to cross the Wallace Line, a boundary between Australia and the Asian islands where many species are found in abundance on one side and rarely or not at all on the other.

“Previously, we did not consider tarantulas to be good dispersers. While continental drift certainly played its part in their history, the two Asian colonization events encourage us to reconsider this narrative. The microhabitat differences between those two lineages also suggest that tarantulas are experts at exploiting ecological niches, while simultaneously displaying signs of niche conservation,” said Foley.

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Materials provided by Carnegie Mellon University. Original written by Jocelyn Duffy. Note: Content may be edited for style and length.

Now, a team led by McGill University researchers and members of Canada’s CHIME Fast Radio Burst collaboration has established that FRBs include radio waves at frequencies lower than ever detected before, a discovery that redraws the boundaries for theoretical astrophysicists trying to put their finger on the source of FRBs.

“We detected fast radio bursts down to 110 MHz where before these bursts were only known to exist down to 300 MHz,” explained Ziggy Pleunis, a postdoctoral researcher in McGill’s Department of Physics and lead author of the research recently published in the Astrophysical Journal Letters. “This tells us that the region around the source of the bursts must be transparent to low-frequency emission, whereas some theories suggested that all low-frequency emission would be absorbed right away and could never be detected.”

The study focussed on an FRB source first detected in 2018 by the CHIME radio telescope in British Columbia. Known as FRB 20180916B, the source has attracted particular attention because of its relative proximity to Earth and the fact that it emits FRBs at regular intervals.

The research team combined the capacities of CHIME with those of another radio telescope, LOFAR, or Low Frequency Array, in the Netherlands. The joint effort not only enabled the detection of the remarkably low FRB frequencies, but also revealed a consistent delay of around three days between the higher frequencies being picked up by CHIME and the lower ones reaching LOFAR.

“This systematic delay rules out explanations for the periodic activity that do not allow for the frequency dependence and thus brings us a few steps closer to understanding the origin of these mysterious bursts,” adds co-author Daniele Michilli, also a postdoctoral researcher in the Department of Physics at McGill.

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University of Queensland researcher Dr Anthony Romilio was part of the team that investigated the track, originally found by Associate Professor Lida Xing from the China University of Geosciences (Beijing).

“This footprint was made by a herbivorous, armoured dinosaur known broadly as a stegosaur — the family of dinosaurs that includes the famed stegosaurus,” Dr Romilio said.

“Like the stegosaurus, this little dinosaur probably had spikes on its tail and bony plates along its back as an adult.

“With a footprint of less than six centimetres, this is the smallest stegosaur footprint known in the world.

“It’s in strong contrast with other stegosaur prints found at the Chinese track site which measured up to 30 centimetres, and prints found in places like Broome in Western Australia where they can be up to 80 centimetres.”

The tiny footprint has similar characteristics of other stegosaur footprints with three short, wide, round toe impressions.

However researchers found the print wasn’t elongated like larger counterpart prints discovered at the track sites, which suggests the young stegosaur had a different behaviour.

“Stegosaurs typically walked with their heels on the ground, much like humans do, but on all fours which creates long footprints,” Dr Romilio said.

“The tiny track shows that this dinosaur had been moving with its heel lifted off the ground, much like a bird or cat does today.

“We’ve only previously seen shortened tracks like this when dinosaurs walked on two legs.”

Associate Professor Xing said that it was plausible young stegosaurs were toe-walkers.

“This could be possible as this is the ancestral condition and a posture of most dinosaurs, but the stegosaur could also have transitioned to heel-walking as it got older,” Dr Xing said.

“A complete set of tracks of these tiny footprints would provide us with the answer to this question, but unfortunately we only have a single footprint.”

Finding the tiny tracks on crowded track sites will be challenging for the researchers.

“The footprints made by tiny armoured dinosaur are much rarer than those formed by other groups of dinosaurs,” Associate Professor Xing said.

“Now that our study has identified nine different dinosaur track sites from this locality, we will look even closer to see if we can find more of these tiny tracks.”

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Within the Mathematics, Mechanics, and Materials Unit at the Okinawa Institute of Science and Technology Graduate University (OIST), postdoctoral researcher, Dr. Vikash Chaurasia, and Professor Eliot Fried have been using energy minimization techniques to look at charged proteins on biological particles. Previously they researched cholesterol molecules but when the pandemic hit, they realized that with the methods they had developed could be applied to the new virus. They collaborated with researchers Mona Kanso and Professor Jeffrey Giacomin, from Queen’s University in Canada, to take a close look at SARS-CoV-2 and see how the shape of the virus’ ‘spikes’ (which are officially called peplomers) aid its success at spreading so prolifically. Their study was recently published in Physics of Fluids.

“When one envisions a single coronavirus particle, it is common to think of a sphere with many spikes or smaller spheres distributed across its surface,” said Dr. Chaurasia. “This is the way the virus was originally modeled. But this model is a rough sketch and over the last year, we’ve come to learn much more about what the virus looks like.”

Instead, Dr. Chaurasia pointed out, the ‘spikes’ of the coronavirus particle are actually shaped like three small spheres stacked together to form a triangular shape. This is an important consideration because the shape of a viral particle can influence its ability to disperse.

To understand this, imagine a ball moving through space. The ball will follow a curve but, as it does this, it will also rotate. The speed at which the ball rotates is called its rotational diffusivity. A particle of SARS-CoV-2 moves in a similar way to this ball although its suspended in fluid (specifically, tiny droplets of saliva). The rotational diffusivity of the particle impacts how well it can align with and attach itself to objects (such as a person’s tissues or cells) and this has been key in its ability to successfully spread from person to person so quickly. A higher rotational diffusivity will mean that the particle shakes and jitters as it follows a trajectory — and thus may have difficulty attaching to objects or efficiently bouncing off an object to continue to move through the air. Whereas a lower rotational diffusivity has the opposite effect.

Another consideration was the charge of each spike. The researchers assumed that each is equally charged. The same charges always repel each other so if there are only two spikes on a particle and they have equal charges, they’ll be situated at either pole (as far away from each other as possible). As more equally charged spikes are added, they become evenly distributed across the surface of the sphere. This provided the researchers with a geometrical arrangement from which they could calculate the rotational diffusivity.

Previously, the researchers looked at a viral particle with 74 spikes. For this new study, they used the same particle but switched out the single-bead spikes for the three-bead triangles. When they did this, the rotational diffusivity of the particle was found to decrease by 39%. Moreover, this trend was found to continue with the addition of more spikes.

This was an important finding — having a lower rotational diffusivity means that the virus particles can better align and attach themselves to objects and people. Thus, this study suggests that the triangular shaped spikes have contributed to the success of SARS-CoV-2.

“We know it’s more complicated than this,” explained Dr. Chaurasia. “The spikes might not be equally charged. Or they might be flexible and able to twist themselves. Also, the ‘body’ of the particle might not be a sphere. So, we plan to do more research in this area.”

An additional interesting feature of this research is its connection to a question asked more than a century ago by physicist J. J. Thomson, who explored how a set number of charges will be distributed across a sphere.

“I find it fascinating that a problem considered more than 100 years ago has such relevance for the situation we’re in today,” said Professor Eliot Fried. “Although this question was first posed primarily from a standpoint of curiosity and intellectual interest, it has turned out to be applicable in unexpected ways. This shows why we mustn’t lose site of the importance of fundamental research.”

The scientists at OIST and at Queen’s University intend to continue to collaborate on this kind of research to shed light on the success of SARS-CoV-2. The researchers at Queen’s University have just been awarded a Mitacs Globalink Research Award to allow for lead author Mona Kanso to travel between Canada and Japan and work more closely with OIST.