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Discover the secrets of science on TV

the panel of top TV producers seeking documentary ideas — Talent seekers – the panel of top TV producers wanting documentary ideas from delegates at the American Association for the Advancement of Science in Boston.

By Matin Durrani in Boston, US

Physics World has been involved in making online videos and what we call “mini documentaries” for more than seven years. But these are mostly low-budget affairs aimed at people who are, by and large, already interested in physics.

So what if you’re a physicist who wants to work with a big-shot producer to make a full-blown, hour-long TV documentary watched by millions? Shows such as Horizon on the BBC or Through the Wormhole with Morgan Freeman on Discovery’s Science Channel get massive audiences, putting you in touch with far more people than most scientists could ever dream of.

A special session at this year’s annual meeting of the American Association for the Advancement of Science had some of the answers. It brought together a bevvy of top TV producers (see slide above) who shared their tips on how scientists should pitch ideas for documentaries to them. A further session will be held tomorrow to let scientists propose real ideas in a kind of TV-science speed-dating.

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US policy chiefs explain how to handle Trump

At the AAAS meeting in Boston, February 2017, Neal Lane introduces John Holdren (left), Kerri-Ann Jones (centre) and Rosina Bierbaum — Speaking out – Neal Lane introduces John Holdren (left), Kerri-Ann Jones (centre) and Rosina Bierbaum at the 2017 meeting of the American Association for the Advancement of Science in Boston.

By Matin Durrani in Boston, US

I’m here at the 2017 meeting of the American Assocation for the Advancement of Science in Boston, where the theme is “Serving society through science policy”. The focus was picked last year, but it turned out to be an auspicious choice with the election of Donald Trump throwing the science community into uncharted policy waters.

Trying to make sense of what life will be like for US scientists under the Trump administration were five people with extensive experience of working closely with recent US presidents.

Chairing the session was Neal Lane, who served as Bill Clinton’s presidential science adviser for two years in the 1990s. Also present was physicist John Holdren, who spent eight years until last month as Barack Obama’s science chief, for which the audience gave him a generous round of applause.

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Churchill discusses aliens, quantum films make the cut, graphene in a dress

By Sarah Tesh

Last September, the Centre for Quantum Technologies at the National University of Singapore invited people to submit short films about quantum physics for their Quantum Shorts 2016 competition. Both scientists and filmmakers alike have made the short list, which has just been released. The films could be about the science, history, theories, technologies or philosophies of quantum mechanics – anything that sparked the imagination. The online competition has been going since 2012 and alternates between short films and flash fiction, and this year the films will be screened at a film festival as well. The shortlist comprises of 10 films, all available to watch and vote for online. There are supernovae, love triangles, muesli with bananas and cats – everything you could want to help explain quantum physics.

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Building blocks of life found on Ceres

Organic compounds have been discovered on the surface of the dwarf-planet Ceres. The Visual and Infrared Spectrometer (VIR) on NASA’s Dawn spacecraft detected the compounds while in orbit around the minor planet. The team investigating the data suggests that the organics were formed on Ceres, indicating the planet has a more complex chemical history than previously assumed.

The organics detected are aliphatic compounds – chain molecules primarily comprised of carbon and hydrogen atoms. They were found moving across the south-western floor of a 50 km-wide crater called Ernutet, as well as in patches to the crater’s north-west. Organic compounds are volatile and would be easily destroyed by the intense heat of an asteroid impact. Also, their distribution across the surface does not seem to match with the ejecta from any specific crater.

The discovery was made by a team led by Maria Cristina De Sanctis of the National Institute of Astrophysics in Rome, during a survey of Ceres’ surface between 60° north and 60° south. At higher latitudes the data was too noisy to be useful. “I’ve never seen anything like this anywhere in the solar system,” De Sanctis told Physics World. “It’s difficult to see how the organics could have come from an impactor.”

If they were not delivered by an impactor, the organics must have somehow formed on Ceres itself. De Sanctis admits it is not certain whether they were made on the surface, or instead formed inside the dwarf planet before welling up from a water-rich layer below. Although all the raw materials for the organic compounds – carbon, hydrogen, nitrogen, phyllosilicates, water – are present on Ceres, “it is not very clear to me how the organics could have formed in situ,” says Thomas Prettyman of the Planetary Science Institute in Arizona.

Sampling Ceres

Knowing exactly which aliphatic compounds are present would help to solve this puzzle, but they all have similar infrared emission lines centred around 3.4 μm, making it difficult for VIR to distinguish between different compounds. “We know for sure that they are organics, but we can’t say what kind of organics,” says De Sanctis. “There could be several different types together, or just one.”

An image of the terrain around crater Ernutet, as seen by Dawn. Warmer colours indicate the densest concentrations of organics. — The terrain around crater Ernutet, as seen by Dawn. Warmer colours indicate the densest concentrations of organics. (Courtesy: NASA/JPL–Caltech/UCLA/ASI/INAF/MPS/DLR/IDA)

At the comet 67P Churyumov–Gerasimenko, the European Space Agency’s Rosetta mission was able to distinguish between organics because “the identification of specific molecules is best done by mass spectroscopy”, says ESA’s Michael Küppers. Rosetta was able to fly through the gaseous hood of the comet, called the coma, and sample organics directly with its mass spectrometer. Dawn does not have this option around Ceres.

Instead, team-member and Dawn’s principal investigator, Christopher Russell from the University of California, Los Angeles, says that “the community is talking about a lander, which should be much easier to accomplish than landing on a larger body like Mars, and we know where the interesting sites on Ceres are.”

Planetary designation

It’s not the first time that organics have been found in the asteroid belt. Remote observations of several asteroids have hinted at the presence of organics, but it is unclear if they were deposited by impact or interplanetary dust. Meanwhile at the 92 km-wide Occator Crater on Ceres – home to bright patches of material known as “faculae” that are thought to be salt (possibly sodium carbonate) brought to the surface by water – there is an unidentified emission signature that could also be organics.

“What this discovery does is go beyond the wet-planet paradigm to Ceres being a possible incubator of more complex chemistry,” says Russell. Although classified as a dwarf planet, Ceres is considered to be a protoplanet – the leftover hulk of a planet that never fully formed. Russell believes that the International Astronomical Union (IAU) misunderstood Ceres’ nature when they promoted it to dwarf planet in 2006.

“The IAU chose to classify planetary status by size, which is flawed reasoning,” he says. “Planetary designation should be judged on the interior properties instead. Ceres is a protoplanet or a small planet because of its internal chemistry. It did something besides just melting material, it made new [organic] material.”

Although there is no suggestion of life on Ceres, aliphatic compounds ranging from methane and ethane to more complex compounds including kerite and asphaltite are thought to be essential building blocks of life’s simplest biochemical mechanisms, making their discovery relevant to astrobiologists. “The presence of organics is a very important discovery,” says Prettyman, before concluding that “it may be very challenging to determine their origins.”

The findings are presented in Science.

Flash Physics: Massive planet sets star pulsating, new deputy director of BNL’s Computational Science Initiative, UAE sets out Mars vision

Massive planet sets star pulsating

A distant star pulses each time its planet hurtles close by. 400 light-years away, the star HAT-P-2 is orbited by a massive gas giant. The planet, called HAT-P-2b, is eight times the mass of Jupiter and has a highly eccentric orbit, meaning that it passes close by the star and then hurtles far out before returning to loop back around. Using 350 hours of observations taken by NASA’s Spitzer Space Telescope, a team of scientists was studying the temperature changes in the planet, when the researchers noticed unexpected, tiny vibrations in the star’s brightness. They found that each time the planet came close to the star, the star’s light pulsed. Indeed, the oscillations correspond to the harmonics of HAT-P-2b’s orbital frequency. After ensuring the vibrations were not caused by the telescope, Julien de Wit from the Massachusetts Institute of Technology (MIT) in the US and colleagues suggest the planet may actually be large enough to periodically distort the star during its eccentric orbit. This goes against previous theoretical models and predictions regarding a planet’s relationship with the star it orbits. How the planet might be affecting the star remains unknown, however. “It’s a mystery, but it’s great,” says de Wit, “because it demonstrates our understanding of how a planet affects its star is not complete.” The study is presented in The Astrophysical Journal Letters.

United Arab Emirates sets out Mars vision

The United Arab Emirates (UAE) has announced an ambitious plan to create a human settlement on Mars within the next 100 years. The “Mars 2117” project was unveiled by Sheikh Mohammed bin Rashid Al Maktoum, ruler of Dubai and the UAE’s vice president at the 5th World Government Summit in Dubai. The first phase of the Mars 2117 project will concentrate on achieving “scientific breakthroughs” to help colonise Mars by focussing on developing faster ways to get to and from the red planet as well as how to sustain life. Mars 2117 will initially begin with a UAE-based scientific team before being extended to include international scientists. “The new project is a seed that we plant today, and we expect future generations to reap the benefits, driven by its passion to learn to unveil a new knowledge,” says Sheikh Mohammed. “The landing of people on other planets has been a long-time dream for humans. Our aim is that the UAE will spearhead international efforts to make this dream a reality.” The country has already invested around £4bn in its space agency, which was created in 2014, and the UAE is also working to send a probe to Mars in 2021, dubbed Mars Hope.

Francis Alexander new deputy director of BNL’s Computational Science Initiative

Physicist Francis Alexander has been named deputy director of the Computational Science Initiative at the US Department of Energy’s (DOE’s) Brookhaven National Laboratory. Alexander was previously at the DOE’s Los Alamos National Laboratory for more than 20 years where he held a number of leadership positions including leader of the Computer, Computational, and Statistical Sciences (CCS) Division’s Information Sciences Group and leader of the Information Science and Technology Institute. “I was drawn to Brookhaven by the exciting opportunity to strengthen the ties between computational science and the significant experimental facilities – the Relativistic Heavy Ion Collider, the National Synchrotron Light Source II, and the Center for Functional Nanomaterials [all DOE Office of Science User Facilities],” says Alexander. “The challenge of getting the most out of high-throughput and data-rich science experiments is extremely exciting to me.” Alexander will work with CSI director Kerstin Kleese van Dam to expand the department’s research portfolio and promote data-driven discovery. Alexander will also act as BNL’s primary liaison to national security agencies, as well as develop partnerships with other national laboratories and research institutions.

You can find all our daily Flash Physics posts in the website’s news section, as well as on Twitter and Facebook using #FlashPhysics.

The many faces of Marconi

Guglielmo Marconi caricatured by Spy (Sir Leslie Matthew Ward) for Vanity Fair, 1905 — Electric personality: Guglielmo Marconi caricatured by Spy (Sir Leslie Matthew Ward), 1905. (Courtesy: Sir L Ward, *Vanity Fair* 1905/Wellcome Trust)

In July 1897 the young Italian entrepreneur Guglielmo Marconi was granted what is considered to be the world’s first wireless patent. To commercialize and popularize the embryonic technology that was wireless telegraphy, he founded his own company – the Wireless Signal and Telegraph Company, which later became Marconi’s Wireless Telegraph Company. The Italian innovator – and future Nobel physics laureate – had an ambitious vision for an interconnected, global wireless network, modelled on the existing global telegraphic network that spanned the globe in the late 19th century.

The success of Marconi – the man, as well as his many companies in the fields of wireless communications, broadcast radio and early television – is well documented in many a popular and academic publication. And yet, despite continued interest in Marconi’s public and private life throughout his time and even today, Marc Raboy’s Marconi: the Man Who Networked the World is the first detailed, thorough and academically rigorous biography of Marconi. Raboy presents a critical account of Marconi’s personality and private life, connecting the many different strands – commercial, political, social and public – surrounding Marconi, as well as covering the inventor’s important contributions to wireless communications and other technologies that have impacted our modern world.

The book neatly divides Marconi’s life into five chronological sections, describing various aspects and impacts of Marconi’s personality. The first section, “The Prodigy”, looks at Marconi’s early life as he grew up in Bologna, with his Italian–Irish family – his mother was Annie Jamieson of the Irish whiskey family. In 1896 at the age of 22, Marconi moved to Britain to begin his early commercial and international work in wireless technology, which led to his ground-breaking transatlantic transmission in December 1901.

Around this narrative of the more well-known parts of Marconi’s life, Raboy also describes more personal tales, including Marconi’s early and secretive romantic entanglements, such as his unfulfilled engagement to the American Josephine Holman.

The book then moves on to “The Player” – a section that examines the eight busy years between the transatlantic transmission in 1901 and Marconi’s Nobel prize (awarded jointly with German wireless pioneer Ferdinand Braun) in 1909. The book deftly intertwines Marconi’s charming personality and highly successful use of publicity – Marconi presented himself as a celebrity inventor – with the early commercial and international development of the various Marconi companies. Raboy also points out Marconi’s less charming use of legal action, including patent litigation, in an attempt to stifle competition.

In “The Patriot”, Raboy moves on to wider changes in the Marconi Company, such as the appointment of new managing director Godfrey Isaacs, and the ups and downs of Marconi and his companies before and during the First World War. The latter included the life-saving and headline-grabbing application of wireless telegraphy during the sinking of the RMS Titanic in 1912. Another point of note was the “Marconi Scandal”, also in 1912, in which the company lost its lucrative contract with the British government to construct the Imperial Wireless Scheme, in light of political deals and share-rigging. Raboy also describes how Marconi reconsidered his role, and that of wireless communications, in the aftermath of the world wars and the global devastation they had wrought.

The final two sections of the book – “The Outsider” and “The Conformist” – look at the inventor’s first forays into Italian fascism in the 1920s and 1930s, as well as the end of his first marriage and subsequent second marriage. Raboy also explores Marconi’s interest and involvement in wider technical applications of wireless technologies including beam navigation for ships and aircraft, broadcast radio, and short-wave long-distance radio. Marconi conducted many experiments in these new and promising technologies, with much of his experimental programme conducted on his floating laboratory, the yacht Elettra after whom his daughter Elettra from his second marriage was named (and not the other way round).

Raboy concludes with Marconi’s somewhat early and unexpected death in July 1937 at the age of 63, his heritage and the concerted efforts of Marconi and later his family to control his reputation and guarantee his legacy – a task continued by the Marconi Company publicity department well beyond Marconi’s death into the late 20th century.

In this readable and authoritative biography running to nearly 900 pages, Raboy provides a critical and illuminating study of how Marconi’s complicated personality and personal attributes – an irresistible combination of magnetic charm, singular vision and ruthless grand ambition – shaped his own life as well as the lives of many others. Unlike previous studies of Marconi, Raboy does not gloss over the more negative aspects of the inventor’s personality: his absence as a father; his many romantic affairs; his multiple and frequent threats of patent litigation to limit commercial competition; his use of the work of others (only some of whom worked for him and his companies); his (ultimately unfulfilled) monopolistic ambitions for a global wireless network; and his close involvement with Italian fascism towards the end of his life. Instead, Raboy argues that it was these very personality traits that shaped and determined the majority of Marconi’s business and technological choices, many of which contributed ultimately to the interconnected wireless world we live in today.

In claiming Marconi as “the man who networked the world”, Raboy is perhaps on shakier ground, as he downplays the importance and successes of the pre-existing global telegraph network in order to present Marconi as a unique visionary. Despite this somewhat overly ambitious underlying premise, Raboy’s volume is a major and long overdue biography that combines archival sources and publications to create a highly readable and fascinating insight into the public and private aspects of Marconi’s life. The book will appeal to popular and academic readers alike, including those with an interest in early wireless and telecommunications technologies, as well as those interested in a more insightful and illuminating look at Marconi’s life.

2016 Oxford University Press 872pp £25hb

Between the lines

Heat waves and halcyon days

Trying to explain a scientific concept in 30 seconds or less is a rather difficult but worthy task. In 30-Second Meteorology: the 50 Most Significant Events and Phenomena, Each Explained in Half a Minute nine leading UK meteorologists tackle the basic terms and ideas we need to know to understand our planet’s ever-changing weather and climate. The book is divided into seven sections including the global atmosphere, the Sun and extreme weather. Each section opens with a glossary and includes a profile of a stalwart of the field – such as Edward Norton Lorenz and Milutin Milankovitch (though one can’t help noticing that not a single female scientist gets a mention). Edited by the UK Met Office’s Adam Scaife, each page-long entry includes a one-sentence definition of the concept, a slightly longer factoid, the main entry (each of which is only about 200 words) and a cross-reference of related topics. The book’s layout (an entry on one page with an illustration opposite) is consistent, making it an easy reference book or one that you can just dip into. The book’s distinctive art style, a cross between digital mixed-media and old-school collage, makes it visually appealing. Readers will find that most entries clearly explain everything from snow and sundogs to space weather and the polar vortex. What is slightly off-putting, though, is the section entitled “Can we change the weather?” Oddly, it does not talk about geo-engineering; instead, it covers topics such as the ozone hole and global warming. While the book does not shy away from discussing global warming, the section-title’s tone suggests that its effects may be seen in the future, rather than acknowledging that they are already in play. This seems like pandering to climate-change sceptics, something that no scientific book can afford to do today.

Ivy Press 2016 160pp £14.99hb

Camera celestia

Astronomy and the coffee-table book are very common bedfellows, and for good reason. As our imaging and processing capabilities have excelled over the past 30 years since the launch of the Hubble Space Telescope (HST), we have been privy to some truly stunning images of the cosmos. Naturally then, incandescent celestial images have graced the glossy pages of many a book, and Astrophotography: the Most Spectacular Astronomical Images of the Universe is no different in that aspect. Written and compiled by Cardiff University astronomer Rhodri Evans, the book includes nearly 200 pictures from across the electromagnetic spectrum – X-ray, radio, infrared, microwave and, of course, visible light – compiled for your viewing pleasure. The book opens with information on 19 different ground-based telescopes and 10 different spacecraft that have taken the images, and also includes a detailed glossary. Divided into five parts, the pictures span from the solar system, to the Milky Way, to our Local Group of galaxies, beyond the Local Group and, finally, to the “edge of the universe”. It is fair to wonder just who would want to buy a large, hardbound book of astronomy images when the Internet is overrun with them, but this is where Evans’ commentary comes into its own. Anyone with even a passing interest in astronomy is sure to have come across the iconic HST image of the “pillars of creation” in the Eagle nebula. The original 1995 image and the updated version from 2014 are compared and contrasted in the book, with differences in the imaging quality as well as physical changes pointed out, giving this popular image new context. It’s also good to see additions from the most recent space missions, such as pictures of Pluto and Comet 67P via New Horizons and the Rosetta mission, mixed in with old favourites. Pick up a copy of Astrophotography to update yourself on some of the most iconic and awe-inspiring celestial images of our times.

Andre Deutsch 2016 192pp £25hb

Enjoy the rest of the February 2017 issue of Physics World in our digital magazine or via the Physics World app for any iOS or Android smartphone or tablet. Membership of the Institute of Physics required

Blocking the symmetry of motion

A mechanical metamaterial that responds strongly to motion from one direction, while blocking it in the other, has been developed by an international team of researchers. The research, which in principle at least breaks a fundamental assumption of mechanical engineering, could have applications ranging from shock absorption to prosthetics and robotics.

An important property of the new material is its ability to overcome reciprocity – a fundamental principle that governs many physical systems. It refers to the symmetrical transmission of energy between two points in space. Regardless of which point the energy is travelling from and to, it should behave identically in both directions. Mechanically, reciprocity implies that if you push on one side of an object, you should get the same response if you were to push on the opposite side – the motion travels through the object symmetrically.

Andrea Alù at the University of Texas at Austin in the US has previously worked on overcoming reciprocity for wave propagation. His past work includes producing acoustic isolators that transmit sound in only one direction and antennas that will not listen to their own echo.

Collaborative idea

While Alù was on sabbatical, he and Corentin Coulais of the Foundation for the Fundamental Research on Matter Institute for Atomic and Molecular Physics (AMOLF) in the Netherlands had an idea about a non-reciprocal metamaterial. Coulais previously worked with carefully designed mechanical metamaterials that respond in unusual ways to stimuli, and the researchers decided to combine their interests to produce a mechanical metamaterial that would behave non-reciprocally in response to time-invariant forces.

The researchers designed two non-reciprocal metamaterials that respond much more strongly to forces from one side than from the other. The first was a rubber-made, centimetre-scale metamaterial with a structure like a fish skeleton. It comprised springs arranged with a central spinal column and ribs protruding out at an angle. This structure showed non-reciprocity, but only when sufficiently high forces were applied – springs are fundamentally elastic, so they must be stretched enough to trigger significant rotation of the springs before the onset of nonlinearity.

Squares and diamonds

The researchers’ second design, therefore, consists of freely hinging squares and diamonds, which begin to rotate in response to even small displacements and are therefore non-reciprocal for even small forces. “If you pull it from the right, you displace the material, but only close to where you push or pull on it,” explains Coulais. “If you now pull on it on the other side, you induce a motion that propagates through the material.” Alù offers a more fundamental interpretation, saying the structure supports “edge modes” analogous to those in a topological insulator, which can travel through the material in only one direction. Such a material could potentially be useful in prosthetics such that an arm can be actuated from one side but not break what it picks up.

“Nonlinear systems with structural instability are not a completely new idea,” explains Nicholas Fang of Massachusetts Institute of Technology (MIT), but he adds: “I think this is a great example of curiosity driven problems…and I think there will very likely be potential applications.” John Pendry of Imperial College London believes the work is “interesting and worthwhile”, marking a further generalization of the concept of non-reciprocity. He cautions, however, that nonlinearity could make the systems very difficult to handle. “You’re restricted to certain values of the input signal to get the effect you want,” he says, “because the nonlinearity might generate quite a different response if you have a huge input or, typically, systems are linear for very small inputs.”

The researchers are aware of this problem, and Coulais says they are currently contemplating a non-reciprocal metamaterial than could be reconfigured by electric or magnetic fields. “One of the directions we’ve been discussing is to see if we could control the non-reciprocity in real time, such that you could have it for any amount of force,” he says. Non-reciprocal materials could be used to develop novel actuators; improve the efficiency of energy absorption, conversion and harvesting, and even be used in soft robotics.

The research is published in Nature.

Spin-out success: a career using MRI technology

When the world’s first experiments on magnetic resonance imaging (MRI) took place at the University of Nottingham in the late 1960s, I was working down the hall from Peter Mansfield’s pioneering group, in a related subgroup that focused on nuclear magnetic resonance spectroscopy (NMR). It was an exciting time: you could have an idea in the coffee room, go down to the lab and try it, and almost write a paper about it the same day because nobody had ever thought about it before. Nowadays, people have to work for years to produce meaningful results, but at that time it was so new, the whole process took a matter of weeks.

After I got my PhD at Nottingham, I spent two years as a postdoctoral assistant at the University of Leeds, where I used NMR to study liquid crystals. Following that, I became an academic at the University of Surrey, where I founded a research group developing MRI techniques for medical physics applications.

Practically minded

I love physics, but as MRI became increasingly biological in nature, I realized I was more comfortable on the technological side

I love physics, but as the field of MRI matured, it became increasingly biological and biochemical in nature, and I realized that I was more comfortable on the technological side. Really, I’m a frustrated engineer! That led me to get into more applied work, and in 1985 I spun out my own company from the university. Surrey Medical Imaging Systems (SMIS) ran successfully for 15 years and was responsible for a number of innovations, including the world’s first PC-based MRI systems; the first human limb scanner; and some of the world’s first high-field human MRI systems.

It’s very difficult to get a company going, and the achievements of SMIS wouldn’t have been possible without the money we raised from venture capital firms. However, from a founder’s perspective, their contributions came with a big downside: loss of control. By the late 1990s, I’d gone from owning 2/3 of the business to owning less than 1%, and it had also become clear that the company wasn’t going to fulfil our investors’ goal of becoming the next General Electric or Siemens. So they decided to break the company up and sell it off. However, I was able to license the core technology and use it to form the company now known as MR Solutions – this time without venture capital involvement.

My focus was on the development of more sophisticated spectrometers – the “brains” of an MRI scanner, which carry out all the control, data acquisition and processing functions – and also more compact and effective MRI scanners for preclinical (that is, non-human) research. Our most significant innovation has been the elimination of the liquid helium cooling system for high-field superconducting MRI systems. In order to make a high-strength magnet, the magnet coils need to carry high current. In practice, this can be achieved only by using superconducting wire, which must be operated at or below 4 K.

Traditionally, this very low temperature was achieved by immersing the magnet coils in a bath of liquid helium, but this is undesirable for several reasons. The world’s supply of helium is limited, which makes it expensive, and “wet” magnets (those that use liquid helium) also require bulky and expensive safety features to guard against damage from a helium gas leak (for example, due to heating when the magnet undergoes a “quench” and ceases to be superconducting). So the challenge presented to our development team was to develop a cooling system that did not require helium, but could reliably cool the entire magnet uniformly.

The development of the helium-free technology was carried out in collaboration with our magnet partners, who have experience of building small magnets for other physics applications. The new design incorporates superconducting magnet coils that are cooled by direct conduction with an “off the shelf” cryocooler fridge unit. These systems have an up-front cost about half that of a traditional magnet, and they are compact and relatively lightweight (350 kg instead of more than two tonnes). This means they can be housed in ordinary laboratories, where space is at a premium, and they do not require an emergency exhaust system. In addition, regular top-ups of helium are no longer necessary.

Our scanners are used by university research departments and industrial firms all over the world

The other significant innovation was making it possible to perform other types of imaging (such as PET, SPECT and CT imaging) either in series or in parallel with the MRI imaging. This generates a fusion of complementary images and data and saves significant amounts of research time. Our scanners are used by university research departments and industrial firms (mainly pharmaceutical companies) all over the world, and their main application is imaging small animals. Being able to conduct many types of imaging in one unit is very helpful for these users, since it eliminates the need to move sedated animals around between imaging systems that, previously, may have been located in different laboratories.

Skills needed

We began shipping the compact, high-powered cryogen-free MRI scanner in 2012, and since then, our revenue has grown by more than 50%. In 2016 MR Solutions received the Queen’s Award for Enterprise (Innovation) at Buckingham Palace in recognition of our technical innovations.

At the moment, the biggest challenge we face is the availability of skilled staff here in the UK. The country’s manufacturing base has been eroded, and it’s hard to find experienced engineers, manufacturing managers and MRI physicists. Many overseas students do PhDs in MRI in the UK, but they don’t have the right to work here after they graduate and getting work permits for them is challenging. Also, the skills we need are often different from what the modern MRI research environment provides. A lot of students work on commercial clinical scanners for their PhDs, but we need people who can take a piece of equipment apart and rebuild it.

We do train people with an MRI physics background in these “hard skills”, though, and at the end of 2016, we were able to bring our magnet production closer to home, with a new magnet factory in Abingdon, Oxfordshire. This makes it possible to control quality and production, and to continue developing our technologies. So while it’s not as easy to make breakthroughs now as it was in the early days of MRI, I hope someday that we will see these compact magnets used in a clinical setting to treat patients.

Flash Physics: magnetizing cockroaches, a young supernova, construction begins on dark-matter detector

Magnetizing cockroaches in life and death

Dead cockroaches have different magnetic properties compared to their living counterparts, according to Tomasz Paterek from Nanyang Technical University in Singapore and colleagues, who put groups of dead and alive cockroaches in a magnetic field of 1.5 kG, which is 100 times stronger than a fridge magnet. After 20 minutes, they measured the strength of magnetization and how long it took to decay. Although both types became magnetized, the dead cockroaches’ field decayed in roughly 50 hours while the process took barely 50 minutes for the living creatures. Using mathematical models, the researchers suggest that the magnetization is caused by magnetic iron-sulphide particles around 100 nm in diameter. These become aligned with the external field and then lose alignment because of Brownian motion. The group attributes the different decay rates to the viscosity of the particle-containing medium inside the cockroaches. For the living bugs, this medium has a low, runny viscosity, while for dead cockroaches the medium begins to harden, consequently slowing the decay. As the magnetic sensing in living cockroaches is too slow for biological uses, the researchers suggest that it is used to influence chemical processes. Although questions remain, the study could help bioengineers to design new magnetic sensors. The preprint is available on the arXiv server.

A 3 hour-old supernova has been observed

Artist's impression of the supernova 3 hours after exploding — The supernova was observed 3 hours after exploding, giving insight into its life just before. (Courtesy: Ofam Yaron)

A star’s violent death has been caught on camera mere hours after it exploded. In October 2013, the fully automated Intermediate Palomar Transient Factory (iPTF) survey spotted the early stages of a type II supernova in a nearby galaxy. A supernova is the last, dramatic stage of massive star’s life. Type II is the most common category of supernova and occurs when a star 8–40 times more massive than the Sun has collapsed under its own gravitational fields and then exploded. Spectra of type II supernovae also show the presence of hydrogen, but astronomers know little about the evolution and environment of these massive stars before they explode, as it requires witnessing the very early stages of the supernova and such events are extremely rare. So once iPTF spotted the event only three hours after it occurred, researchers jumped at the opportunity to perform tests on the young supernova. These included X-ray, ultraviolet, infrared and visible-light photometry and spectroscopy. Ofer Yaron from the Weizmann Institute of Science in Israel and colleagues report the findings in Nature Physics. As the supernova was in its early stages, the scientists were able to spot dense debris encircling the star – something that was not predicted by current stellar models. Although they admit several scenarios could explain the surrounding debris, the researchers suggest that the star, a red supergiant, had been rapidly ejecting material over the year before it exploded. “It’s as if the star ‘knows’ its life is ending soon,” says Yaron. Over five days the material was completely swept away by the explosion. As type II supernovae are the most common, the observations made by Yaron and colleagues suggest that all massive stars may be unstable prior to their dramatic demise.

Construction begins on dark-matter detector

A photograph of scientists working at the the LZ Dark Matter Experiment — Construction on the LUX-ZEPLIN dark matter detector can begin. (Courtesy: http://lz.lbl.gov/)

The US Department of Energy (DOE) has given the green light for construction of the LUX-ZEPLIN dark-matter detector to start. Located around 1.6 km underground at the Sanford Underground Research Facility in Lead, South Dakota, the experiment will search for weakly interacting massive particles – a leading dark-matter candidate – by using a tank filled with 10 tonnes of ultra-pure liquid xenon. If a dark-matter particle collides with a xenon atom, it will then produce a flash of light that is picked up by around the 500 light-amplifying tubes lining the tank. LUX-ZEPLIN is expected to be around 50 times more sensitive than its predecessor, the Large Underground Xenon experiment. The start of construction comes after the DOE granted the experiment “critical decision 3”, which accepts the final design and allows building work to begin. The DOE’s Lawrence Berkeley National Laboratory is leading the construction of the facility, which includes around 220 participating scientists from 38 institutions around the world. LUX-ZEPLIN is expected to start operation in April 2020.

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