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Improving soft skills crucial to keeping women in science, finds study

Early-career women in science who spend time developing their “soft skills” see a boost in their self-confidence and likelihood to stay in work. That is according to a study carried out by sociologists in the US, which also finds that the COVID-19 pandemic may have led to a drop in soft skills among women in science, technology, engineering and mathematics (STEM) subjects (Proc. Natl Acad. Sci. 119 e2123105119).

Interpersonal skills such as teamwork, communication and resilience can be harder to teach than technical, cognitive and achievement-related abilities, often referred to as “hard skills”. Soft skills can, however, be important predictors of career success. Research has shown that due to structural and social barriers in STEM, particularly in male-dominated fields, women can struggle with high-status soft skills such as influencing colleagues and building strong strategic networks. Combined with lower levels of professional confidence, this leads to women leaving STEM fields at higher rates than men.

Julia Melin and Shelley Correll from Stanford University developed and evaluated a six-month online programme to improve the soft skills of women in the early stages of STEM careers. It involved providing 44 women at a US biotech company, each of whom had less than 10 years’ work experience, with virtual peer support, one-to-one career coaching and opportunities to develop professional skills. A control group of 200 early-career employees did not receive the online support.

The study began in early 2020, which allowed the researchers to also assess the impact of the COVID-19 pandemic on soft skills among early-career women. A survey measured participants’ self-assessments of their soft skills before and after the programme.

Among early-career women in the control group, perceived soft skills dropped 3.5% compared with the pre-COVID-19 baseline. But those who took part in the online programme experienced a boost of more than 9% in their perceived soft skills. A year after the study, women in the support group were significantly more likely to still be working at the company. The soft-skill training also led to a much bigger rise in managers’ performance ratings, compared with those in the control group.

Women less likely to be included as authors on scientific papers, finds study

Given that issues around retention and advancement of women are not just limited to biotech, Melin told Physics World that their results are likely to apply across STEM fields including physics. Melin adds that she would now like to see STEM companies invest in professional development programmes for employees, especially for early-career women. “Programmes that harness the power of cohorts might be especially important for soft-skill development and ultimately retention,” she says. “Cohort programmes also seem promising for companies adopting hybrid or remote working models, since employees will have less frequent in-person interactions with their colleagues.”

Long-range semiconductor defects come into view

Directly visualizing structural defects in semiconductors on large scales is no easy task. The main microscopy techniques are limited to fields of view measuring just a few tens of nanometres, and they require ultrahigh vacuum, ultralow temperatures, complicated sample preparation and complex setups that make them impractical for many tasks. Now, researchers at the Chinese Academy of Sciences in Beijing have developed a simple and non-invasive alternative: a wet-etching technique that they claim could improve the performance of electronic devices by making it easier to understand their mechanical, electrical and optical properties.

Led by Guangyu Zhang of the Beijing National Laboratory for Condensed Matter Physics and the Songshan-Lake Materials Laboratory in Dongguan, the team developed the method as a simpler way of visualizing structural defects in a typical two-dimensional (2D) semiconductor, monolayer molybdenum disulphide (ML–MoS₂). In the work, the researchers used a wet etching process that enlarged the structural defects in the semiconductor from nano- to micro-sizes, making the defects easier to observe under an optical microscope or atomic force microscope (AFM). The etching process involves applying a solution of 2% calcium hypochlorite by weight to the material for 20 seconds at room temperature, and because the defects are relatively reactive to chemical treatments, the process affects only the defected sites, leaving other areas of the ML–MoS₂ lattice intact.

Triangular pits and trenches

After making the defects bigger, the researchers say they were able to observe 0D point defects (such as sulphur vacancies) and 1D grain boundaries that transformed into triangular pits and trenches, respectively, in different types of ML–MoS₂. These were mechanically exfoliated MoS₂, CVD-grown ML–MoS₂, single domain and CVD-grown ML–MoS₂ films with small and large grain size.

The number of triangular pits reached their maximum after roughly 200 seconds. According to Zhang and colleagues, this indicates that the etching process by hypochlorite ions initiates at inherent defect sites and does not generate new defects, unlike existing selective etching techniques. The increase in the number of pits over time may stem from the different chemical reactivity of different defects, they say.

General technique for directly visualizing defects

MoS₂belongs to a class of materials called 2D transition metal dichalcogenides (2D–TMDs), and the researchers say that their calcium hypochlorite solution can also be used to etch other materials of this type such as WSe₂, MoSe₂, and WS₂. “This indicates that our method is a general technique for directly visualizing defects in 2D–TMDs and has the potential to be applied to other 2D semiconductors,” Zhang says.

“Our simple and non-invasive method can directly visualize the structural defects in 2D–TMDs on a large scale,” he adds. Utilizing this etching technique, the team investigated the intrinsic defects of four types of ML–MoS₂films and found that CVD-grown ML–MoS₂single domain and ML–MoS₂films with large grain size have lowest defect density. This enabled the researchers to understand the relationship between structural defects and performance.

“Being able to direct visualization of the structural defects in 2D semiconductors at a large scale in this way allows us to assess sample quality and could help guide us towards high-quality wafer growth,” he tells Physics World. It also makes it possible to identify relationships between the material’s structure and its performance, and thus to develop high-performance 2D devices towards practical applications, he adds.

Full details of the research are published in Chinese Physics B.

Radiation damage is spotted using calorimetry technique

Material defects caused by radiation damage can be characterized by measuring the energy that the defects release when heated. That is the conclusion of researchers in the US and Finland, who say their new approach could lead to better techniques for quantifying the diminished performance of irradiated materials – something that could have important implications for the operation of ageing nuclear power plants.

Irradiated materials, such as those used in nuclear reactors, are damaged when the absorption of neutrons and other high-energy particles creates atomic-scale defects. This damage can, with time, degrade the material’s overall performance. However, characterizing microscopic damage can be very difficult because even cutting-edge techniques like transmission electron microscopy (TEM) cannot accurately measure the type, size, and density of defects throughout a material.

Energy release

Instead of probing defects directly, Charles Hirst at the Massachusetts Institute of Technology and colleagues looked at how irradiated materials store energy in their atomic-scale defects, and then release this energy when heated. The key to their technique is that this release occurs once a certain energy barrier is reached – a barrier that is specific to the nature of the defect.

To observe this process, they used a technique called differential scanning calorimetry (DSC), which measures the difference between the amount of heat required to raise the temperature of a sample, and a reference material with a well-defined heat capacity.

In this case, the sample was a small titanium nut, irradiated for 73 days, which simulated the radiation it would experience in real nuclear reactor. As a reference, the team used an identical nut that had not been irradiated. In their experiment, they gradually heated the sample and reference from room temperature to 600°C, at a rate of 50°C per minute.

The study revealed that between 300–600°C, excess energy was released from the irradiated nut in two distinct stages, indicating that defects relax at these temperatures through two different mechanisms. Hirst’s team then used molecular dynamics simulations to understand each of these mechanisms.

With TEM, these defects could only be studied at far lower temperatures, therefore the behaviour of defects in the higher temperature range could only be extrapolated by the team. So far, this has allowed them to identify one energy release process. Based on this result, Hirst and colleagues predict that DSC has the potential to uncover many new mechanisms for energy release in other materials, revealing defects that have so far remained hidden to other techniques.

Their approach could be particularly useful for inspecting nuclear reactors. By extracting small samples from reactors, operators could use DSC to better quantify the extent of how a component has degraded from radiation exposure. This could help reactor operators to make more informed decisions about whether components are safe to continue operating. In turn, this could extend the lifetimes of existing nuclear plants – even those considered to be reaching the end of their lifetimes – for decades to come.

The research is described in Science Advances.

Challenges facing Li-ion battery electrolytes and high-energy cathodes

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Advances in materials for high energy, low cost and sustainable lithium ion batteries (LIBs) are vital for the pursuit of net zero emissions and to mitigate climate change.

The positive electrode (cathode) plays a key role in the overall energy, cost and sustainability of the battery. In the near-term, the battery industry is turning to nickel (Ni)-rich layered transition metal oxide cathodes. However, LIBs with Ni-rich cathode chemistry suffer from rapid performance fading issues that presently limit their lifetime.

This webinar discusses the profound impact that the electrolyte composition has on the lifetime of LIBs with Ni-rich cathodes. The complex interactions between Ni-rich cathodes and organic carbonate-based electrolytes at the electrode–electrolyte interface (EEI) are explored in light of recent work, which demonstrates the detrimental effect of ethylene carbonate (EC), a core component in conventional electrolytes, when the battery is charged.

Using a combination of online electrochemical mass spectrometry (OEMS), electrochemical impedance spectroscopy (EIS), solution nuclear magnetic resonance (NMR), transmission electron microscopy (TEM), and inductively coupled plasma-optical emission spectroscopy (ICP-OES), a mechanistic understanding of the degradation processes in EC-containing and EC- free electrolytes is provided.

A perspective on the conflicting electrolyte needs of Ni-rich cathodes and LIB anodes, and the implications of findings for other next-generation cathodes are discussed.

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Wesley Dose is an assistant professor in the School of Chemistry at the University of Leicester. After receiving his PhD in chemistry in 2015 from the University of Newcastle, he held postdoctoral positions in Dr Christopher Johnson’s group at Argonne National Laboratory, and Prof. Michael De Volder and Prof. Clare Grey’s groups at the University of Cambridge. His post-doctoral work focused on the study of advanced electrode materials for next-generation lithium ion batteries; specifically, silicon-based anodes and nickel-rich layered transition metal oxide cathodes. Wesley joined the faculty at Leicester in 2021. His research investigates energy storage materials for applications in various battery chemistries including lithium ion and “beyond” lithium ion.

Future of the International Space Station unclear as Russia announces intention to leave

The future of astronauts in low-Earth orbit remains unclear following Russia’s decision to withdraw from the International Space Station (ISS) after 2024. The move was announced in late July by Yuri Borisov, who replaced Dmitry Rogozin as head of the Russian space agency Roscosmos earlier that month. Russia’s withdrawal will end a two-decade collaboration on the ISS, although Borisov promised that the country would “fulfil all [existing] obligations to our partners” before its partnership ends.

The timing of Borisov’s announcement was surprising given that in early July, NASA and Roscosmos had announced “seat swaps” for astronauts and cosmonauts to fly in the other nation’s spacecraft. As things stand, Russia and NASA’s other partners in the ISS – Canada, Japan and the European Space Agency (ESA) – are contracted to use the station until 2024. But as of now, Russia has not officially informed NASA of any decision to leave the space station. “NASA has not been aware of decisions from any of the partners, though we are continuing to build future capabilities to assure our major presence in low-Earth orbit,” NASA administrator Bill Nelson said in a statement in late July. “NASA is committed to the safe operation of the ISS through 2030 and is co-ordinating with partners.”

It is very, very difficult to imagine a future where ISS can operate without the partners working together
Laura Forczyk

Roscosmos’s decision is assumed to be in response to Western criticism of Russia’s invasion of Ukraine. Roscosmos delayed the launch of several satellites aboard one of its Soyuz rockets from the ESA spaceport in French Guiana after ESA recognized sanctions against Russia in February. Yet general relations among astronauts and cosmonauts on the ISS and between Russian and US space administrators have been mostly cordial. “A lot of trust had built up for a lot of years,” former NASA administrator Jim Bridenstine told Physics World. The issue now is whether the US and partners could potentially operate the ISS until 2030 if Russia does pull out.

Future prospects

The ISS was first occupied by astronauts on 2 November 2000. Since then, modules have been added and astronauts have conducted space walks and studied phenomena ranging from the growth of protein crystals to human muscle atrophy in microgravity. According to Kathryn Leuders, NASA’s associate administrator of human space exploration and operations mission directorate, such research has produced about 400 scientific papers including 185 in the past two years.

As the two key partners in the venture, the US and Russia individually operate the station’s two main segments. The US supplies the structure’s electrical power and Russia the propulsion capability that maintains it in orbit. “The two sections are so interconnected and rely on each other such that it is very, very difficult to imagine a future where ISS can operate without the partners working together,” Laura Forczyk, founder and executive director of space consulting firm Astralytical, told US National Public Radio.

Physically separating the ISS’s two segments would be extremely difficult. And without Russia, NASA would face the issue of how to overcome the station’s tendency to lose height in its orbit. Space analysts see at least a few approaches. NASA could possibly control the orbital boosts directly from Houston rather than Moscow. It might use US or rented Russian spacecraft to nudge the structure higher. More complex would be designing an entirely new propulsion system.

End-of-life plans

Scott Pace, director of George Washington University’s Space Policy Institute, says that Russia’s announcement “is not really a surprise” given today’s less friendly atmosphere. “It’s not particularly productive to react to every statement, but to focus on the facts,” he adds. “We should probably have some back-up thoughts on maintaining the station, but [also] to think of what we do after the ISS ends – it’s not whether but when and how.”

Whatever happens in the next few years, the ISS is now nearing the end of its life. Leading up to 2030, NASA plans to lower the station’s orbit slowly, before allowing it to crash into an uninhabited area of the Southern Pacific Ocean in 2031. Analysts see no likelihood of a successor on the same scale as the football-pitch-sized ISS in the future. “It’s a beautiful thing, but we’re looking at smaller, more specialized stations,” Pace adds. “The future is probably multiple smaller human-tended stations rather than the large assembly.”

NASA has already started to encourage that type of technology. Last year, the agency awarded contracts to three groups to build commercial space stations: Blue Origin, partnering with Sierra Space; Nanoracks, in partnership with Lockheed Martin; and Northrop Grumman. In addition, Axiom Space is developing what it calls “the world’s first commercial space station”. Axiom has announced plans to launch the first component of its station by 2024. However, none of the companies has indicated when they expect astronauts to occupy and run their stations.

The US is also not alone in building the next wave of low-Earth orbit space stations. China, which has been kept out of the ISS collaboration, is expanding its own operational and occupied Tiangong space station, which launched in April 2021. Roscosmos has talked about a launch in 2028 for its first new space station module, although some have expressed scepticism about
that date.

Mariel Borowitz, a specialist in international space policy at the University of Georgia, says that whatever happens in the future, it is unlikely to involve the US and Russia collaborating again. “Russia is partnering with China, not the US, in Moon exploration – all that happened prior to the invasion of Ukraine.”

Uncovering the universe’s invisible secrets

Like many people, I was afraid of the dark as a child. I would struggle to sleep in a pitch-black room, my imagination projecting anything scary onto the space I couldn’t see. Perhaps there are evolutionary reasons for this common fear to do with nocturnal predators, but there’s also a very simple one: sight is the primary sense most of us rely on to collect information about our surroundings. If we can’t see what’s around us, then how can we be sure there are no monsters lurking in the dark?

In astronomy, it turns out, invisible monsters are very real – even if they aren’t the kind that most children are scared of. From black holes to the ancestors of dead galaxies, these elusive cosmic characters are the focus of The Invisible Universe: Why There’s More to Reality than Meets the Eye, by Matthew Bothwell, an astronomer and science communicator at the University of Cambridge, UK.

In the introduction, Bothwell makes a compelling case for studying the unseeable by use of a striking analogy. If we consider the spectrum of visible light to be a single octave on a piano, with red light being the note middle C and blue light, roughly half the wavelength, being the C an octave above, then how far does the full spectrum of electromagnetic (EM) radiation extend? The answer is 65 octaves, “as much as nine grand pianos standing in a line”.

It’s a humbling fact for a species that uses sight as its main sense – and it doesn’t stop there. There are astronomical spectacles that would still elude us even if we could see across all 65 octaves of light. After all, we can’t see black holes because no light of any wavelength can escape them, while dark matter doesn’t seem to interact with EM radiation at all. Meanwhile, gravitational waves are ripples in the fabric of space-time itself rather than anything to do with EM radiation, and all we know about dark energy is that it is causing the universe to expand at an accelerating rate. The Invisible Universe has chapters dedicated to all of these phenomena, describing them vividly while explaining the physics behind them in an accessible manner.

Bothwell approaches each chapter like a detective story: he introduces some unexpected observation, follows the development of theories to explain it, and relates their triumphs or failures. One chapter that particularly swept me along is “Monsters in the dark: the quest to find the Universe’s hidden galaxies”.

Bothwell explains that there is a class of galaxies in the universe that are gargantuan even by galaxy standards – one such behemoth is “big enough to swallow the Milky Way, Andromeda, and all the space between”. But strangely, all the galaxies this size seem to be dead – they no longer actively form stars. The rest of this chapter reads like a cosmic murder mystery, as we look back in time – by looking deeper into space – in search of these galaxies’ ancestors and what killed them off.

Puzzlingly, there are no candidates visible in the images of deep space beamed back by the Hubble Space Telescope that are nearly extreme enough to be those predecessors. But non-visible sub-millimetre observations reveal a new type of galaxy in the early universe, shrouded in dust, that produced stars ten times more rapidly than even “starburst” galaxies nearby. These ancient star factories are excellent candidates for the dead galaxies’ ancestors, but how did they all die off? It is a testament to how much I enjoyed this chapter that I feel I shouldn’t give this spoiler away – but I will say that the resolution does not disappoint.

I also enjoyed the stories of the scientists and engineers that Bothwell weaves throughout the book. One I hadn’t heard before concerned Karl Jansky and Grote Reber, who were early pioneers of radio astronomy. In the early 1930s, Jansky was an engineer working at Bell Labs in the US, trying to get rid of the problem of radio static. While studying this noise, he discovered a type of signal that repeated every 23 hours and 56 minutes.

Bothwell explains that this is a tell-tale sign of something from beyond the solar system. Although we think of a day as being 24 hours long, it actually only takes 23 hours and 56 minutes for the Earth to rotate once relative to the Milky Way. During that time the Earth has moved a bit further around the Sun, so the planet needs to rotate for another four minutes for the Sun to reach the original point in the sky. But in 23 hours 56 minutes, we’re lined up with our galaxy again. Therefore a signal with this period is likely to be coming from outside of the solar system – indeed, Jansky was detecting radio waves from centre of the Milky Way.

Incredibly, the astronomy community as a whole took little notice of Jansky’s results when he first published them. Bothwell describes this as being for one simple reason: “the world of radio engineering was just too far removed from the world of astronomy”.

But Reber – an engineer who designed electric equipment for radio broadcasts – was fascinated with this noise from outer space. He built his own radio telescope in his back garden in Chicago, and, from the mid-1930s to the mid-1940s, was “the only radio astronomer in the world”.

Reber took courses in physics and astronomy at his local university, to help him understand his observations, and he was the first person to detect radio waves emanating from hot gas clouds where stars were being born. According to Bothwell, Reber was “the last of the amateur ‘outsider’ scientists”, who “through painstaking and meticulous work managed to change the scientific world”.

This story and many others throughout the book underline the crucial importance of technology for progress in astronomy – and the current technology is remarkable. For example, to detect gravitational waves, the Laser Interferometer Gravitational-Wave Observatory (LIGO) has to be able to sense a squeeze and stretch of less than the diameter of a proton, and to image black holes’ event horizons, the Event Horizon Telescope achieves a resolution equivalent to reading a newspaper in New York using a telescope in London.

So the feats of engineering that humans have achieved to detect astronomical phenomena are perhaps as awe-inspiring as the phenomena themselves. And Bothwell reminds us that there’s more to come, with projects underway to take capabilities to the next level across all fields of astronomy. For example, the European Space Agency is currently building the first space-based gravitational wave detector. The Laser Interferometer Space Antenna (LISA) will be able to detect gravitational waves with much longer wavelengths than LIGO can because it’s mirrors will be an incredible 2.5 million kilometres apart compared to LIGO’s 4 km.

By highlighting the future of astronomy, the book pre-empts its own expiry date, well aware that it is likely an incomplete tour of the invisible, with future technology destined to uncover yet more monsters in the dark. When the book was written, the James Webb Space Telescope had not yet been launched. Now it is in space, already sending back breath-taking infrared images of the universe.

But I think the book’s timing is actually perfect. In an era when so many pioneering new projects are underway, it has reignited my excitement about what weirder and more wonderful curiosities they might find. And, even if it means the book becomes slightly out-of-date, I get the strong impression that the author is pretty excited about that too.

2021 Oneworld Publications 320pp £18.99hb
2022 Oneworld Publications 320pp £10.99pb

Aftermath of explosive stellar merger seen in a new light

The aftermath of the merger of a neutron star with another star has been observed using millimetre-wavelength light for the first time. The distant merger occurred when the universe was about 5.5 billion years old and was immediately followed by one of the most energetic short-duration gamma-ray bursts (SGRBs) ever spotted by astronomers. It also left behind one of the most luminous afterglows ever seen. These latest millimetre-wavelength observations of that afterglow could help astronomers understand how heavy elements are forged in such cataclysmic mergers.

The SGRB is called GRB 211106A and its gamma-rays were spotted in 2021. Now, Tanmoy Laskar and colleagues have used the Atacama Large Millimetre/submillimetre Array (ALMA) radio telescope in Chile to observe millimetre-wavelength light from the afterglow. In the electromagnetic spectrum, this light falls between the infrared and microwaves.

Explosive mergers involving neutron stars are believed to forge heavy elements like platinum and gold. So, understanding how these mergers proceed is important to understanding how galaxies evolve – and ultimately how heavy elements end up in planets like Earth.

“Very few SGRB afterglows have been detected at radio wavelengths. This is because, although they are very luminous, these explosions take place in distant galaxies, which means the light from them can be quite faint for our telescopes on Earth,” explains Laskar, who will soon join the University of Utah. “Only about half a dozen SGRB radio afterglows are known. And despite almost two decades of searching, none had been detected at millimetre wavelengths.”

Useful emissions

Laskar explains that finding millimetre emissions from an SGRB is particularly useful because the light is unaffected by passing through ionized gas in the Milky Way, something that can make the interpretation of observations of longer wavelength radio waves challenging. Millimetre-light is also immune to the quantum effects that can make the interpretation of high-energy X-rays from distant sources difficult.

Team member Wen-fai Fong, who is at Northwestern University, adds that millimetre wavelengths allow astronomers to “see through” obstructing material that is normally opaque to other wavelengths. “These observations revealed a large amount of dust in the vicinity of this gamma-ray burst,” she adds. “This explains why we did not observe any visible light from the burst.”

Indeed, the combining of observations in varying wavelengths of light was the key to revealing a clearer picture of this powerful event. Northwestern’s Genevieve Schroeder tells Physics World that combining millimetre observations of GRB 211106A with X-ray data showed the team just how energetic and wide the gamma-ray burst was.

Laskar adds, “Learning about these properties helps us better understand the progenitors of these extreme explosions — neutron star mergers”.

Fast moving jets

“When the stars merge, the resulting explosions are accompanied by jets of material moving at close to the speed of light,” says Laskar. “When one of these jets is pointed at Earth, we observe a short pulse of gamma-ray radiation, an SGRB.”

The gamma-ray signal is fleeting – lasting just a fraction of a second – so it is difficult to use a SGRB alone to pinpoint the location of the merger. Fortunately, when the jet strikes gas surrounding the merger, it creates a longer-lasting afterglow that can be seen by astronomers. “Capturing the afterglow light is essential for figuring out which galaxy the burst came from and for learning more about the burst itself,” Laskar explains.

Nevertheless, Schroeder says that the team’s success was not guaranteed. “This observation was the first time we have pointed ALMA at a SGRB, and we were only able to detect the afterglow due to ALMA’s remarkable sensitivity. Previous millimetre observations of SGRBs have resulted in non-detections due to the less sensitive telescopes, so this burst really highlights ALMA’s amazing capabilities.”

Because GRB 211106A has been studied across multiple wavelengths as the afterglow faded, Fong says that the team probably will not look at this particular merger with ALMA again.

While gravitational waves have been seen from neutron star mergers, they were not seen from GRB 211106A. This is because the signal would have been too faint for existing gravitational-wave detectors to observe. However, Fong points out that future generations of gravitational wave detectors will soon be able to detect mergers as distant as GRB 211106A.

“That will be a really exciting era, as it will become routine to detect SGRBs in tandem with their gravitational waves.”

The team’s findings are described in a paper on arXiv. The paper has been accepted for publication in The Astrophysical Journal Letters.

Octopus-inspired glove grabs underwater objects using LIDAR

Inspired by the way the skin on octopus arms works, researchers at Virginia Tech in the US have developed a new rapidly switchable adhesive that sticks securely to objects underwater. The material could find use in robotics, healthcare and in manufacturing for assembling and manipulating wet objects.

Adhesives that work underwater are difficult to make. This is because the hydrogen bonds and van der Waals and electrostatic forces that mediate adhesion in dry environments are much less effective in water. The animal world, however, contains lots of examples of strong adhesion in moist conditions: mussels secrete special adhesive proteins, creating a sticky plaque to attach to wet surfaces; frogs channel fluid through structured toe pads to activate capillary and hydrodynamic forces; and cephalopods like the octopus use suckers to adhere to surfaces via suction.

Strong adhesive bond

Cephalopod grippers are particularly good at holding things underwater. Octopi, for example, have eight long arms covered with suckers that can grab onto objects like prey. Shaped like the end of a plumber’s plunger, the suckers adhere to an object, quickly creating a strong adhesive bond that is difficult to break. “The adhesion can be quickly activated and released,” explains study team leader Michael Bartlett, “and the octopus controls over 2000 suckers across eight arms by processing information from diverse chemical and mechanical sensors.”

Indeed, an octopus’ sensing apparatus consists of a photoreception system that uses its eyes; mechanoreceptors that detect fluid flow, pressure, and contact; and chemoreception tactile sensors. Each sucker is independently controlled to activate or release adhesion – something that does not exist in synthetic adhesives.

The new Virginia Tech octopus-inspired adhesive consists of a silicone elastomer stalk capped with a stretchable pneumatically-actuated elastomer membrane to control adhesion. The stalk is made by 3D printing moulds and the silicone elastomer is then cast and cured. The adhesive element is connected to a pressure source that supplies positive, neutral, and negative pressure to control the shape of the active membrane.

“This design allows us to switch adhesion 450 times from the on to off state in less than 50 ms,” says Bartlett. “We tightly integrated these adhesive elements with an array of micro-LIDAR optical proximity sensors that sense how close an object is.”

The researchers then connected the suckers and LIDAR through a microcontroller for real-time object detection and adhesion control.

Glove with synthetic suckers and sensors

Underwater, an octopus winds its arms around objects and can attach to a variety of surfaces, including rocks, smooth shells and rough barnacles using its suckers. Bartlett and colleagues mimicked this by making a glove with synthetic suckers and sensors tightly integrated together. This device, dubbed Octa-glove, can detect differently-shaped objects underwater. This automatically triggers the adhesive so that the object can be manipulated.

“By merging soft, responsive adhesive materials with embedded electronics, we can grasp objects without having to squeeze,” said Bartlett. “It makes handling wet or underwater objects much easier and more natural. The electronics can activate and release adhesion quickly. Just move your hand toward an object, and the glove does the work to grasp. It can all be done without the user pressing a single button.”

These capabilities, which mimic the advanced manipulation, sensing and control of cephalopods, could find applications in the field of soft robotics for underwater gripping, applications in user-assisted technologies and healthcare, and in manufacturing for assembling and manipulating wet objects, he tells Physics World.

Several gripping modes

In their experiments, the researchers tested several gripping modes. They used a single sensor to manipulate delicate, lightweight objects and found that they could quickly pick up and release flat objects, metal toys, cylinders, a spoon and an ultrasoft hydrogel ball. By then reconfiguring the sensors to that multiple sensors were activated, they could grip larger objects such as plate, a box and a bowl.

The Virginia Tech team, reporting its work in Science Advances, says that there is still much to learn, both about how the octopus controls adhesion and manipulates underwater objects. “If we can better understand the natural system, this will allow to create more advanced bio-inspired, engineered systems,” says Bartlett.

Babies have an innate understanding of symmetry, we fall foul of chorizogate, astronomers love science fiction

You are never too young to start learning about physics – and now researchers in Europe have backed this up by showing that babies just seven months old have a grasp of symmetry.

Irene de la Cruz-Pavía at the University of the Basque Country, Judit Gervain of the University of Padua and colleagues showed nearly 100 babies mosaic patterns in a study that was done at the University of Paris. The linear patterns had varying degrees of symmetry (see figure) and the babies were able to discriminate between patterns that were structurally symmetric and patterns that were asymmetric.

“Babies as young as seven months have a robust, automatic ability to detect that a structure is symmetrical. This ability coincides with those found in studies we conducted using other stimuli, such as sign language or speech, demonstrating that babies are simply very good at detecting structures and regularities,” says de la Cruz-Pavía.

I believe it was the Nobel laureate Philip Anderson who famously said, “It is only slightly overstating the case to say that physics is the study of symmetry,” so it looks like babies are physicists by nature.

The research is described in a paper in PLOS ONE.

Spicy space sausage

Like many other media outlets, Physics World gleefully reported last week how a photograph of a slice of chorizo had gone viral after prominent French physicist Etienne Klein joked on Twitter that it was the latest image from the James Webb Space Telescope.

Klein apologized for the prank after admitting it was just a piece of sausage from his fridge, but it looks like we need to say sorry too. That’s because, if we’d bothered to dig a tiny bit deeper, we’d have realised that the image had originally been tweeted a day before Klein by theoretical astrophysicist Peter Coles at Maynooth University in Ireland.

As Coles explains on his Telescoper blog, he posted the image on 30 July with the caption “Those JWST images just get better and better”, whereas Klein tweeted the same photo on 31 July. Coles, however, admits that it wasn’t even his image in the first place. “I didn’t make the picture and don’t remember where I got it from, though it was probably here,” he writes on his blog, referring to a tweet from 2018 by a user called Jan Castelmiller, who claimed the chorizo was the red-coloured “blood” Moon seen during a lunar eclipse.

The mystery of the stellar sausage deepens.

Sci-fi confession

I have a confession to make about science fiction: I can take it or leave it. Although I did a PhD in physics and I have since been writing about science for decades, I don’t really find it that compelling in an artistic or literary sense. Sure, I loved watching the original Star Trek series when I was a kid and I do enjoy the occasional sci-fi blockbuster. But you could probably count the number of sci-fi novels I have read over the past 25 years on one hand.

As a result, I had assumed that most people who dealt with science on a professional level shared my sci-fi ambivalence. So, I was surprised to discover that there appears to be a strong correlation between having a love for science fiction and being a professional astronomer. That is the finding of Elizabeth Stanway, who is an astronomer at the UK’s University of Warwick. Stanway conducted two surveys that asked astronomers about their attitudes towards science fiction and whether an interest in science fiction influenced their decision to pursue careers in science.

In one survey of more than 200 UK astronomers, a whopping 94% of respondents expressed an interest in science fiction. Furthermore, 69% said that science fiction had influenced their life or career choices. Writing in a paper on arXiv that reports her findings, Stanway says “This study provides strong statistical evidence for the role of science fiction in influencing the adoption of astronomical careers”.

Ask me anything: Taghi Amirani – a physicist turned documentary-film maker

What skills do you use every day in your job?

Physics and film-making have been intertwined throughout my career since I was an undergraduate. In 1984 I made the unusual suggestion to the physics department at the University of Nottingham that my final-year project should be a film instead of a lab project. Rather than conduct a physics experiment that needed writing up, I would make a documentary about black holes.

After weeks of back-and-forth and negotiations that went all the way up to the heads of the science faculty, the Nottingham physicists displayed remarkable open-mindedness and agreed. Shades of Black became my first film and launched 38 years of film-making adventures. Every skill I developed in making that project a reality, I use to this day.

Taking a leap of faith into the unknown, honing persuasive powers to attract funders and collaborators, hard-nosed and persistent research, perseverance in the face of obstacles and trusting my instincts are some of the skills that have helped me. All of these culminated in my latest film, a theatrical feature called Coup 53. Every scientific endeavour requires an analytical mind driven by intense curiosity. So does documentary-making. Shades of Black was about going back in time to uncover the secrets of the universe. Coup 53, the story of the 1953 MI6/CIA coup in Iran, is about uncovering dark secrets buried deep in history.

What do you like the best and least about your job?

What I like best about being a documentary maker is that I can pick a subject I am curious about and take a deep dive into it until I find a compelling story worth telling. The serendipity of unexpected connections and revelations is pure joy when combined with artistic expression to tell a story that is personally meaningful and resonates with a wide audience. You take what seems like a personal obsession, turn it into a film that requires an army of collaborators to bring it to fruition, and then stand at the back of a cinema and watch it grip and move total strangers gathered in the dark. That human connection is precious beyond words.

For the duration of a production, you become so immersed and absorbed in a new subject that you can almost pass as an expert, albeit in a small sub-section. The learning never stops. This was particularly true in making Coup 53, for which I was privileged to work with the legendary Walter Murch (Apocalypse Now, The Godfather, The English Patient). It was physics that brought us together. Walter was editing Particle Fever – a documentary about the discovery of the Higgs boson, when we met in New York in 2012. Bonding over physics and film-making, I never imagined that I would end up working with Walter on the most important film of my life. He has not only made me a better filmmaker, but our collaboration made me a better human being. This is the kind of experience that transforms a job into a calling.

What I like least about my job is that I love it so much that I occasionally work for no pay. This is a habit I am working hard to break.

What do you know today that you wish you knew when you were starting out in your career?

Uncertainty is good. Having a five-year plan or a 10-year plan is pointless if you’re a creative soul. Don’t worry about having a career. Find what you love and keep on doing it. Trust your process and go with the flow because things will almost always work out. Embrace your mistakes. Take more risks. Sometimes not getting what you want is the best thing that can happen to you.

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